Obesity is heart disease killer in its own right, irrespective of other risk factors

Obesity is a killer in its own right, irrespective of other biological or social risk factors traditionally associated with coronary heart disease, suggests research published online in Heart.

17 feb 2011--Increasing weight is associated with a higher prevalence of known risk factors for coronary artery disease, such as diabetes, high blood pressure and cholesterol. And it has been assumed that these have been responsible for the increased risk of heart disease seen in obesity, say the authors.

The research team tracked the health of more than 6,000 middle aged men with high cholesterol, but no history of diabetes or cardiovascular disease, for around 15 years.

After excluding men who had cardiovascular problems or died within two years of the start of monitoring, to correct for any bias, 214 deaths and 1,027 non-fatal heart attacks/strokes occurred during the whole period.

The risk of a heart attack was compared across categories of increasing body mass index (BMI), using two different approaches.

One simply corrected for any differences in the age or smoking status of the men, while the second corrected for cardiovascular risk factors such as high cholesterol and blood pressure, deprivation and any medications the men were taking.

Not unexpectedly, the results showed that the higher a man's weight, the higher was his likelihood of having other risk factors for cardiovascular disease. And there was no increased risk of a non-fatal heart attack with increasing BMI, (when using either approach)

But the risk of death was significantly higher in men who were obese - a BMI of 30 to 39.9 kg/m².

In the model simply correcting for age and smoking, this risk was 75% higher. And despite correcting for known cardiovascular risk factors, medication, and deprivation in the second model, the risk was still 60% higher.

Inflammation is a strong factor in fatal cardiovascular disease, and obesity is increasingly being recognised as an inflammatory state, which may partly explain how obesity is linked to heart disease, say the authors. This has implications for treatment and prevention, they add.

In an accompanying podcast, which expands on the findings, lead author Dr Jennifer Logue, of the British Heart Foundation Cardiovascular Research Centre, at the University of Glasgow, cautions that the number of obese men in the sample was small, so the results need to be replicated elsewhere.

But she says, this is mainly because when the study started 20 years ago, the prevalence of obesity was low. But all that has now changed.

"The obesity generation is coming of age. We are going to see more and more complications from obesity, and coming at an earlier age," she warns.

Provided by British Medical Journal

Hearing loss associated with development of dementia

Older adults with hearing loss appear more likely to develop dementia, and their risk increases as hearing loss becomes more severe, according to a report in the February issue of Archives of Neurology.

16 feb 2011--By the year 2050, an estimated 100 million people or nearly one in 85 individuals worldwide will be affected by dementia, according to background information in the article. Interventions that could delay the onset of dementia by even one year could lead to a more than 10 percent decrease in the prevalence of dementia in 2050, the authors note. "Unfortunately, there are no known interventions that currently have such effectiveness," they write. "Epidemiologic approaches have focused on the identification of putative risk factors that could be targeted for prevention based on the assumption that dementia is easier to prevent than to reverse. Candidate factors include low involvement in leisure activities and social interactions, sedentary state, diabetes mellitus and hypertension."

To assess another potential risk factor, hearing loss, Frank R. Lin, M.D., Ph.D., of Johns Hopkins Medical Institutions, Baltimore, and colleagues studied 639 individuals age 36 to 90 without dementia. Participants initially underwent cognitive and hearing testing between 1990 and 1994 and were followed for the development of dementia and Alzheimer's disease through May 31, 2008.

Of the participants, 125 had mild hearing loss (25 to 40 decibels), 53 had moderate hearing loss (41 to 70 decibels) and six had severe hearing loss (more than 70 decibels). During a median (midpoint) follow-up of 11.9 years, 58 individuals were diagnosed with dementia, including 37 who had Alzheimer's disease.

The risk of dementia was increased among those with hearing loss of greater than 25 decibels, with further increases in risk observed among those with moderate or severe hearing loss as compared with mild hearing loss. For participants age 60 and older, more than one-third (36.4 percent) of the risk of dementia was associated with hearing loss.

The risk of developing Alzheimer's disease specifically also increased with hearing loss, such that for every 10 decibels of hearing loss, the extra risk increased by 20 percent. There was no association between self-reported use of hearing aids and a reduction in dementia or Alzheimer's disease risk.

"A number of mechanisms may be theoretically implicated in the observed association between hearing loss and incident dementia," the authors write. Dementia may be overdiagnosed in individuals with hearing loss, or those with cognitive impairment may be overdiagnosed with hearing loss. The two conditions may share an underlying neuropathologic process. "Finally, hearing loss may be causually related to dementia, possibly through exhaustion of cognitive reserve, social isolation, environmental deafferentation [elimination of sensory nerve fibers] or a combination of these pathways."

"If confirmed in other independent cohorts, the findings of our study could have substantial implications for individuals and public health. Hearing loss in older adults may be preventable and can be practically addressed with current technology (e.g., digital hearing aids and cochlear implants) and with other rehabilitative interventions focusing on optimizing social and environmental conditions for hearing. With the increasing number of people with hearing loss, research into the mechanistic pathways linking hearing loss with dementia and the potential of rehabilitative strategies to moderate this association are critically needed."

More information: Arch Neurol. 2011;68[2]:214-220.

Provided by JAMA and Archives Journals

Fiber intake associated with reduced risk of death

Dietary fiber may be associated with a reduced risk of death from cardiovascular, infectious and respiratory diseases, as well as a reduced risk of death from any cause over a nine-year period, according to a report posted online today that will be published in the June 14 print issue of Archives of Internal Medicine.

15 feb 2011--Fiber, the edible part of plants that resist digestion, has been hypothesized to lower risks of heart disease, some cancers, diabetes and obesity, according to background information in the article. It is known to assist with bowel movements, reduce blood cholesterol levels, improve blood glucose levels, lower blood pressure, promote weight loss and reduce inflammation and bind to potential cancer-causing agents to increase the likelihood they will be excreted by the body.

Yikyung Park, Sc.D., of the National Cancer Institute, Rockville, Md., and colleagues analyzed data from 219,123 men and 168,999 women in the National Institutes of Health-AARP Diet and Health Study. Participants completed a food frequency questionnaire at the beginning of the study in 1995 and 1996. Causes of death were determined by linking study records to national registries.

Participants' fiber intake ranged from 13 to 29 grams per day in men and from 11 to 26 grams per day in women. Over an average of nine years of follow-up, 20,126 men and 11,330 women died. Fiber intake was associated with a significantly decreased risk of total death in both men and women—the one-fifth of men and women consuming the most fiber (29.4 grams per day for men and 25.8 grams for women) were 22 percent less likely to die than those consuming the least (12.6 grams per day for men and 10.8 grams for women).

The risk of cardiovascular, infectious and respiratory diseases was reduced by 24 percent to 56 percent in men and 34 percent to 59 percent in women with high fiber intakes. Dietary fiber from grains, but not from other sources such as fruits, was associated with reduced risks of total, cardiovascular, cancer and respiratory disease deaths in men and women.

"The findings remained robust when we corrected for dietary intake measurement error using calibration study data; in fact, the association was even stronger with measurement error correction," the authors write.

"The current Dietary Guidelines for Americans recommend choosing fiber-rich fruits, vegetables and whole grains frequently and consuming 14 grams per 1,000 calories of dietary fiber," the authors conclude. "A diet rich in dietary fiber from whole plant foods may provide significant health benefits."

More information: Arch Intern Med. Published online February 14, 2011. doi:10.1001/archinternmed.2011.18

More candor urged in care of dying cancer patients

14 feb 2011-- Patients don't want to hear that they're dying and doctors don't want to tell them. But new guidance for the nation's cancer specialists says they should be upfront and do it far sooner.

The American Society of Clinical Oncology says too often, patients aren't told about options like comfort care or even that their chemo has become futile until the bitter end.

To help families broach the topic, too, the group developed an easy-to-read booklet about those choices, from standard care to symptom relief, and advice about what to ask to maximize remaining time.

"This is not a 15-minute conversation, and it should not happen in the back of the ambulance on the way to the ICU at 3 in the morning," says ASCO chief executive Dr. Allen Lichter. "When everyone is well and has their wits about them, it's time to start the process."

The guidance and booklet - available at http://www.cancer.net - mark an unusually strong push for planning end-of-life care, in a profession that earns more from attacking tumors than from lengthy, emotional discussions about when it's time to stop.

"This is a clarion call for oncologists . to take the lead in curtailing the use of ineffective therapy and ensuring a focus on palliative care and relief of symptoms throughout the course of illness," the guidance stresses.

But it's part of a slowly growing movement to deal with a subject so taboo that Congress' attempt to give such planning a nudge in 2009 degenerated into charges of "death panels."

Now consider a program in Pittsburgh named Closure. In so-called "community conversations," the program teaches families how to talk with each other and their doctors about what they want - and want to avoid - in their final days. Created by the Jewish Healthcare Foundation, sessions have spread to hospitals, religious centers and neighborhoods around the city, and a website opened last month at http://www.closure.org .

The sessions are frank. Doctors tell of entering hospital rooms late at night asking for resuscitation preferences should a very ill patient worsen only to find relatives didn't know their loved one was that sick.

"There is going to be, over the next few years, a groundswell of people telling physicians, `I don't want to go out in excruciating pain, short of breath, alone, surrounded by lights and sirens and people pounding on my chest,'" predicts Dr. Jonathan Weinkle, a primary care physician who advises the program.

"Everybody wants a good death but not a moment too soon, but they don't have the language to ask for it."

Closure participant Pearl Moore, a retired Pittsburgh oncology nurse, urges people to start planning before they're ever sick, when it's easier to discuss.

Moore's mother died of stomach cancer without health workers or family ever discussing the inevitable. Haunted, she returned to college to specialize in cancer nursing. She helped her patients discuss quality of life, "to be able to live until they died, is the way I put it," Moore says.

And years ago she prepared her own living will and other health care directives, giving copies to her daughter, Cheryl, as soon as she was grown.

"Remembering my mother, we had the discussion," says Moore.

It's not clear how often the still healthy like Moore do that kind of advance planning.

But the oncology society says it isn't happening enough with the very sick. Fewer than 40 percent of advanced cancer patients have what it calls a "realistic conversation" with their doctors about what to expect and their choices of care.

The consequences: Patients increasingly are receiving aggressive chemotherapy in the last two weeks of life. They're spending more of their last months hospitalized. They're not told that a lot of expensive, side effect-prone therapies buy at best a few more months.

They think palliative care - specialized care for pain, nausea, shortness of breath - means giving up when it should be offered with standard anti-tumor care.

And they're not referred to hospice until their final days. Lichter tells of a lung cancer patient who spent his last days on a ventilator, unable to say goodbye and incurring $25,000 in hospital bills, because his family called 911 when he became short of breath. Hospice care could have eased that symptom at home.

The society plans by summer to issue detailed guidelines to help doctors conduct those tough conversations. Meanwhile, among its advice for patients:

-Ask your doctor about pros and cons of different treatment options, and discuss your priorities, including quality of life, with the doctor and family. You can change your mind later.

-Ask about palliative care for symptom relief along with your chemo. A major study last summer found that combination helped advanced lung cancer patients live a few months longer, because people who feel better can tolerate more anti-cancer treatment.

-A living will ensures health workers and family know your choices when you cannot communicate, including whether you would want such things as a feeding tube.

-Most clinical trials for experimental treatments won't admit people who've already undergone multiple treatments, so consider that option early.

More information:
Cancer group: http://www.cancer.net

Closure: http://www.closure.org

State advance directives: http://www.caringinfo.org/PlanningAhead

Non-dopaminergic drug preladenant reduces motor fluctuations in patients with Parkinson's disease

Preladenant, a non-dopaminergic medication, reduces off time in patients with Parkinson's disease receiving standard dopamine therapy, an international study led by the University of South Florida found.

12 feb 2011--Results of the double-blind, randomized clinical trial are reported online today in the journal Lancet Neurology. The findings suggest that preladenant may offer a new supplemental treatment for Parkinson's disease without some of the complications of levodopa and other standard dopamine treatments.

"The goal of treatment is to provide the best possible function and quality of life to patients over time," said lead author Dr. Robert A. Hauser, director of the Parkinson's Disease and Movement Disorders Center at USF. "After a few years, many patients find that their traditional Parkinson's disease medications wear off after a few hours leading to a re-emergence of symptoms. In this study, preladenant was shown to reduce off time, thereby affording patients more time through the day with better function."

Dr. Hauser and colleagues evaluated the safety and effectiveness of a range of doses of preladenant in 253 patients experiencing "wearing off" symptoms from their levodopa therapy. The patients were also receiving other available anti-parkinsonian drugs, such as dopamine agonists and/or entacapone.

The 12-week study found that the addition of 5 and 10 mg of preladenant twice daily significantly reduced "off time" -- the re-emergence of troublesome motor symptoms such as slowness, stiffness, tremors, and immobility – when compared to patients receiving similar doses of placebo. Futhermore, preladenant significantly increased "on time" – the period during which patients' Parkinson's symptoms were adequately controlled --.without significantly worsening dyskinesia (involuntary twisting, turning movements). The doses were well tolerated, and the incidence of treatment-related adverse effects was similar for patients receiving preladenant and placebo.

In Parkinson's disease, the brain's dopamine-producing cells falter and die, leading to movement-related or motor symptoms such as tremors, stiffness, slowness, and balance problems.

Levodopa, a compound converted into dopamine in the brain, is still the gold standard therapy for Parkinson's, but as the disease advances this standard drug works for increasingly shorter time periods. As a result, patients begin to experience impaired movement before their next scheduled dose of medication. The re-emergence of symptoms accompanying this "off-time" can make it difficult for patients to perform even the most basic functions, such as walking and dressing. In addition, over time patients tend to develop a sensitivity to levodopa therapy during "on-time" resulting in involuntary twisting, turning movements known as dyskinesia.

Currently available drugs widely used to treat Parkinson's disease correct for the loss of the neurotransmitter dopamine – either by boosting available dopamine in the brain or directly stimulating dopamine receptors. New ways to treat the disease that better address motor fluctuations without adverse side effects continue to be sought. Preladenant is a non-dopaminergic medication that targets adenosine A2A receptors in the motor control areas of the brain. It may offer advantages over dopamine medications, possibly including fewer side effects.

The clinical trial was conducted at 44 sites in 15 countries. Preladenant is an investigational medicine and is not approved for use.

Provided by University of South Florida

Stroke rehab doesn't have to be high-tech to help

12 feb 2011-- The largest study ever on stroke rehabilitation found that doing physical therapy at home improved walking just as well as a high-tech treadmill program.

More surprising, patients who started rehab late - six months after their strokes - still improved. It's long been thought that there was little to gain from rehab after half a year.

"We now have evidence, for the first time, that a prolonged course of therapy will have benefits," said Dr. Jeffrey Saver, director of the stroke center at the University of California, Los Angeles. "For virtually everyone, we should be doing more intensive therapy than we are."

He had no role in the federally funded study, which was led by Duke University researchers and discussed Friday at an American Stroke Association conference in Los Angeles.

Each year, nearly 800,000 Americans suffer a stroke, and up to two-thirds of survivors have problems walking. Sophisticated machines like robots and weight-supporting treadmills increasingly are being used, but there's limited research on how well they work compared to more traditional therapy.

Such equipment is popular in high-end rehab hospitals like the one in Houston where Rep. Gabrielle Giffords is being treated after her gunshot wound to the head.

The new study included 408 stroke survivors who had trouble walking. On average, they took 1,700 steps a day; normal is 10,000 steps a day. They either traveled to a facility to get high-tech rehab or received physical therapy at home. Some began therapy two months after a stroke; others started six months after the stroke to see if there was a difference.

In high-tech rehab, patients exercised on a treadmill while their weight was supported by an overhead harness. As they gained speed and endurance, they could practice walking on their own.

In the home program, a physical therapist helped patients do exercises to improve strength and balance, and to walk every day.

After a year, both groups made similar improvements in how far and how fast they could walk. However, the treadmill exercisers were more likely to feel dizzy or faint during training, and had a higher risk of falling.

What's more, fewer patients dropped out of the home therapy - 3 percent compared to 13 percent in high-tech rehab.

"There's a tendency in our country to go to high-tech machines," but this study shows they're not always better, said Dr. Walter Koroshetz, deputy director of the National Institute of Neurological Disorders and Stroke, the study's main sponsor.

The bigger message, said study leader Pamela Duncan of Duke University, is that longer treatment and more treatment is best. She said many insurance companies allow 20 visits, while this study gave 36.

The care that stroke victims usually get now - less intense therapy for three to six months - "does not get them to the point where they could be," Koroshetz said.

Doctors are working on a cost comparison, but believe the home program is much cheaper. High-tech rehab requires expensive equipment and two to three therapists per patient; the home program needs only one.

Also at the conference:

Doctors may be missing "silent strokes" in a small but significant number of children with severe anemia, who may be unfairly labeled as slow learners when in fact they have a medical problem.

Strokes have long been known to be a risk for kids with sickle cell anemia, an inherited blood disease that mostly affects blacks. The new study found they also were occurring undetected in children with other conditions that can cause anemia, such as cancer, kidney failure or blood loss from trauma such as a car crash.

"I don't think there's any reason to panic," but doctors need to consider the possibility of stroke when treating any child with severe anemia, said Dr. Michael Dowling of the University of Texas Southwestern Medical Center in Dallas.

Dowling led the study involving 52 children at Children's Medical Center Dallas - 22 with sickle cell and 30 with other causes of severe anemia. MRI scans revealed fresh strokes were occurring in four of the 22 children with sickle cell, and two of the other 30 kids. "Silent strokes" - evidence of damage but no obvious symptoms - were found in three of the 22 sickle cell patients and seven of the other 30.

More information:
Stroke meeting: http://www.strokeconference.org

Sickle cell: http://www.cdc.gov/ncbddd/sicklecell/index.html

Stroke info: http://www.ninds.nih.gov

Limited lymph node removal for certain breast cancer does not appear to result in poorer survival

Among patients with early-stage breast cancer that had spread to a nearby lymph node and who received treatment that included lumpectomy and radiation therapy, women who just had the sentinel lymph node removed (the first lymph node to which cancer is likely to spread from the primary tumor) did not have worse survival than women who had more extensive axillary lymph node dissection (surgery to remove lymph nodes found in the armpit), according to a study in the February 9 issue of JAMA.

11 feb 2011--Axillary lymph node dissection (ALND) has been part of breast cancer surgery since the use of radical mastectomy and reliably identifies nodal metastases. "Sentinel lymph node dissection (SLND) accurately identifies nodal metastasis of early breast cancer, but it is not clear whether further nodal dissection [removal] affects survival," the authors write. "ALND, as a means for achieving local disease control, carries an indisputable and often unacceptable risk of complications such as seroma [a mass or swelling caused by the localized accumulation of serum within a tissue or organ], infection, and lymphedema [condition in which excess fluid called lymph collects in tissues and causes swelling]."

Armando E. Giuliano, M.D., of the John Wayne Cancer Institute at Saint John's Health Center, Santa Monica, Calif., and colleagues conducted a study to determine the effects of ALND on overall survival in patients with SLN metastases treated with lumpectomy (surgical removal of a tumor without removing much of the surrounding tissue or lymph nodes) and radiation therapy. The trial was conducted at 115 sites and enrolled patients from May 1999 to December 2004. Patients were women with T1-T2 (stage of tumor) invasive breast cancer, no palpable adenopathy (enlarged lymph nodes), and 1 to 2 SLNs containing metastases.

Patients with SLN metastases identified by SLND were randomized to undergo ALND or no further axillary treatment. Those randomized to ALND underwent dissection of 10 or more nodes. Of 891 patients, 445 were randomly assigned to the ALND group and 446 to the SLND-alone group.

As expected, there was a difference between ALND and SLND-alone treatment groups in total number of removed lymph nodes and total number of tumor-involved nodes; the median (midpoint) total number of nodes removed was 17 in the ALND group and 2 in the SLND-alone group. At a median follow-up of 6.3 years, there were 94 deaths (SLND-alone group, 42; ALND group, 52). The use of SLND alone compared with ALND did not appear to result in statistically inferior survival, with the 5-year over all survival rates being 92.5 percent in the SLND-alone group and 91.8 percent in the ALND group. Disease-free survival did not differ significantly between treatment groups, with 5-year disease-free survival being 83.9 percent for the SLND-alone group and 82.2 percent for the ALND group.

The rate of wound infections, axillary seromas, and paresthesias (prickly, tingling sensations) among patients in the trial was higher for the ALND group than for the SLND-alone group (70 percent vs. 25 percent).

The authors note that these results suggest that breast cancer patients, such as those in this study, do not benefit from the addition of ALND in terms of local control, disease-free survival, or overall survival, and that ALND may no longer be justified for certain patients. "Implementation of this practice change would improve clinical outcomes in thousands of women each year by reducing the complications associated with ALND and improving quality of life with no diminution in survival."

More information: JAMA. 2011;305[6]:569-575.

Provided by JAMA and Archives Journals

Diet soda may raise odds of vascular events; salt linked to stroke risk

Even if you drink diet soda — instead of the sugar variety — you could still have a much higher risk of vascular events compared to those who don't drink soda, according to research presented at the American Stroke Association's International Stroke Conference 2011.

10 feb 2011--In findings involving 2,564 people in the large, multi-ethnic Northern Manhattan Study (NOMAS), scientists said people who drank diet soda every day had a 61 percent higher risk of vascular events than those who reported no soda drinking.

"If our results are confirmed with future studies, then it would suggest that diet soda may not be the optimal substitute for sugar-sweetened beverages for protection against vascular outcomes," said Hannah Gardener, Sc.D., lead author and epidemiologist at the University of Miami Miller School of Medicine in Miami, Fla.

In separate research using 2,657 participants also in the Manhattan study, scientists found that high salt intake, independent of the hypertension it causes, was linked to a dramatically increased risk of ischemic strokes (when a blood vessel blockage cuts off blood flow to the brain).

In the study, people who consumed more than 4,000 milligrams (mg) per day of sodium had more than double the risk of stroke compared to those consuming less than 1,500 mg per day.

At the start of both studies, researchers assessed diet by a food frequency questionnaire.

NOMAS is a collaboration of investigators at Columbia University in New York and Miami's Miller School of Medicine, launched in 1993 to examine stroke incidence and risk factors in a multi-ethnic urban population. A total of 3,298 participants over 40 years old (average age 69) were enrolled through 2001 and continue to be followed. Sixty-three percent were women, 21 percent were white, 24 percent black and 53 percent Hispanic.

In the soda study, researchers asked subjects at the outset to report how much and what kind of soda they drank. Based on the data, they grouped participants into seven consumption categories: no soda (meaning less than one soda of any kind per month); moderate regular soda only (between one per month and six per week), daily regular soda (at least one per day); moderate diet soda only; daily diet soda only; and two groups of people who drink both types: moderate diet and any regular, and daily diet with any regular.

During an average follow-up of 9.3 years, 559 vascular events occurred (including ischemic and hemorrhagic stroke, which is caused by rupture of a weakened blood vessel). Researchers accounted for participants' age, sex, race or ethnicity, smoking status, exercise, alcohol consumption and daily caloric intake. And even after researchers also accounted for patients' metabolic syndrome, peripheral vascular disease and heart disease history, the increased risk persisted at a rate 48 percent higher.

In the sodium research, 187 ischemic strokes were reported during 9.7 years of follow-up. Stroke risk, independent of hypertension, increased 16 percent for every 500 mg of sodium consumed a day, the scientists calculated. Those figures included adjustment for age, sex, race/ethnicity, education, alcohol use, exercise, daily caloric intake, smoking status, diabetes, high cholesterol, high blood pressure and previous heart disease.

Only a third of participants met the current U.S. Dietary Guidelines for Americans that recommend daily sodium intake fall below 2,300 mg, or about a teaspoon of salt, Gardener said. Only 12 percent of subjects met the American Heart Association's recommendations to consume less than 1,500 mg a day. Average intake was 3,031 milligrams.

"The take-home message is that high sodium intake is a risk factor for ischemic stroke among people with hypertension as well as among those without hypertension, underscoring the importance of limiting consumption of high sodium foods for stroke prevention," Gardener said.

Participants' reporting their dietary behavior is a key limitation of both studies, Gardener said.

In the soda study, investigators also lacked data on types of diet and regular drinks consumed, preventing analysis of whether variations among brands or changes over time in coloring and sweeteners might have played a role.

Provided by American Heart Association

Combining brain imaging, genetic analysis may help identify people at early risk of Alzheimer's

A new study from the Centre for Addiction and Mental Health (CAMH) has found evidence suggesting that a variation of a specific gene may play a role in late-onset Alzheimer's, the disease which accounts for over 90% of Alzheimer's cases. This innovative study has combined genetics and brain imaging to determine who may be at risk for developing late-onset Alzheimer's disease long before symptoms appear.

09 feb 2011--The gene, which is called brain-derived neurotrophic factor (BDNF), is crucial to maintaining healthy function of the brain, primarily the brain's memory centre of the hippocampus and entorhinal cortex, and is responsible for learning and memory function. Past research has found that less BDNF is present in the memory centre of those diagnosed with Alzheimer's disease. However genetic association studies alone have not produced definite findings regarding this gene. Instead, a combination of genetics and brain imaging were used to demonstrate clear effects of this gene in the brain.

In the study published today in the Archives of General Psychiatry, a variation of the BDNF gene called val66met, was tracked and examined in healthy individuals to see what effect it had on the brain. Genotyping was used to determine which study participants carried the gene variation. Then two types of brain imaging -- high-resolution magnetic resonance imaging (MRI) cortical thickness mapping and diffusion tensor imaging (DTI) (an MRI-based technique that measures key structural connections in the brain)-- were applied to measure the physical structures of the brain in each individual. This combination of genetic screening and imaging found that BDNF val66met gene variation influenced exactly those brain structures and connections that deteriorate at the earliest phases of Alzheimer's disease.

"Our sample consisted of healthy adults who passed all cognitive testing and displayed no clinical symptoms of Alzheimer's disease, yet the brains of those who carried the gene variation had differences in their brain structures consistent with changes we see in people at the earliest stages of Alzheimer's disease," said Dr. Aristotle Voineskos, physician and scientist at CAMH, and principal investigator of the study.

Participants who carried the variation were more likely to have thinner temporal lobe structures and disrupted white matter tract connections leading into the temporal lobe - the same structures and neural networks that have deteriorated in the brains of Alzheimer's patients when their brains are examined post-mortem.

"In the past, Alzheimer's disease could only be diagnosed and treated once outward symptoms became present," added Dr. Voineskos. "Early identification is key because, in addition to seeking therapeutic treatments early to reduce suffering, delaying Alzheimer's onset by only two years has the potential of saving the Canadian health care system nearly $15 billion over the next 10 years. The combination of brain imaging and genetics is a key approach that may help us to identify people at risk for Alzheimer's disease."

This breakthrough in image-genetics research can be valuable in the research of other brain diseases and will enable researchers to examine how a gene affects the brain and possibly intervene before a person develops an illness.

Provided by Centre for Addiction and Mental Health

Lifestyle affects life expectancy more than genetics

How long your parents lived does not affect how long you will live. Instead it is how you live your life that determines how old you will get, reveals research from the University of Gothenburg recently published in the Journal of Internal Medicine.

08 feb 2011--It is often assumed that people with parents who lived to be very old are more likely to live to a grand old age themselves.

"But that's just not true – our study shows that hereditary factors don't play a major role and that lifestyle has the biggest impact," says professor emeritus Lars Wilhelmsen, referring to the 1913 Men study that formed the basis of the current research.

Those who did not smoke, consumed moderate amounts of coffee and had a good socio-economic status at the age of 50 (measured in terms of housing costs), as well as good physical working capacity at the age of 54 and low cholesterol at 50 had the greatest chance of celebrating their 90th birthday.

"We're breaking new ground here," says Wilhelmsen. "Many of these factors have previously been identified as playing a role in cardiovascular disease, but here we are showing for the first time that they are important for survival in general."

He believes that it is significant that the research illustrates so clearly that we do not "inherit" mortality to any great extent, but instead that it is the sum of our own habits that has the biggest impact.

"The study clearly shows that we can influence several of the factors that decide how old we get," says Wilhelmsen. "This is positive not only for the individual, but also for society as it doesn't entail any major drug costs."

The study has been published in the Journal of Internal Medicine.

The study of men born in 1913

The 1913 Men epidemiological study started up in 1963. A third of all male 50-year-olds in Gothenburg were called for a check-up that focused on cardiovascular health. Every ten years since, a new group of 50-year-olds has been called in and those who were already taking part in the study have been given another check-up. This has enabled researchers to follow the development of illnesses in a specific age group, and to compare the health of 50-year-olds in 2003 with that of 50-year-olds in 1963, for example. Women have also been included in the study since 2003. Several variables have been studied over the years, including BMI, smoking habits, cholesterol, exercise habits and blood pressure.

The men born in 1913 were examined when they were 50, 54, 60, 67, 75 and 80. Of the 855 men who took part in the study from the start, 111 (13%) were still alive at the age of 90.

Over the years the material has generated many research articles and doctoral theses. An interesting result came in 2008 when researchers were able to show that the drop in the number of smokers, combined with lower cholesterol levels and lower blood pressure, between 1963 and 2003 could offer an explanation for the marked downturn in the number of heart attacks during this 40-year period.

Provided by University of Gothenburg

Physical exercise helps keeps cancer at bay: WHO

The World Health Organisation is advising people engage in at least 150 minutes of "moderate" physical exercise a week to reduce the risk of breast and colon cancers, in new recommendations published Friday.

07 feb 2011--"Cancer is preventable and many cancers are avoidable," said Eduardo Cazap, president of the Union for International Cancer Control (UICC) and one of the authors of the joint "Global Recommendations on Physical Activity for Health".

UICC and WHO experts estimate based on scientific evidence that around 25 percent of breast and colon cancers could be prevented by undertaking physical activity, while exercise can also affect other types of cancers.

"The dose of physical activity required is 150 minutes a week," WHO health promotion expert Tim Armstrong told journalists.

"Most individuals can accomplish it, it's 30 minutes of moderate effort like walking on five days of the week," he explained.

The WHO ranks lack of physical activity alongside tobacco, diabetes and high blood pressure as a health risk, leading to the deaths of 3.2 million people a year.

"Physical inactivity is the fourth leading risk factor for all global deaths, with 31 percent of the world's population not physically active," said Dr Ala Alwan, WHO assistant director-general for non-communicable diseases and mental health.

Some 460,000 women died as a result of breast cancer in 2008 while about 610,000 died of colorectal cancers, according to UN health agency data.

Cazap underlined that one person in two is likely to have a cancer in their lifetime, and the probability grows with ageing.

The UICC believes that the problem of physical inactivity is now extending beyond industralised nations to emerging nations where the population is becoming wealthier.

The recommendations were released for World Cancer Day on Friday.

Report says economic development could change worldwide face of cancer

A new American Cancer Society report says cancers associated with lifestyles and behaviors related to economic development, including lung, breast, and colorectal cancers, will continue to rise in developing countries if preventive measures are not widely applied. The finding comes from the second edition of Global Cancer Facts & Figures and its academic publication, Global Cancer Statistics, published in CA: A Cancer Journal for Clinicians. Both publications are being released on World Cancer Day, Feb. 4, 2011. The latest edition of Global Cancer Facts & Figures includes a special section on cancer in Africa, where according to the International Agency for Research on Cancer (IARC) about 681,000 new cancer cases and 512,400 cancer deaths occurred in 2008, numbers that are projected to nearly double by 2030 due to growth and aging of the population.

06 feb 2011-- According to estimates from IARC, there were approximately 12.7 million new cancer cases worldwide in 2008, 5.6 million of which occurred in economically developed countries and 7.1 million in economically developing countries. There were approximately 7.6 million cancer deaths worldwide in 2008, 2.8 million of which occurred in economically developed countries and 4.8 million in economically developing countries. By 2030, the global cancer burden is expected to nearly double, growing to 21.4 million cases and 13.2 million deaths. And while that increase is the result of demographic changes – a growing and aging population – it may be compounded by the adoption of unhealthy lifestyles and behaviors related to economic development, such as smoking, poor diet, and physical inactivity.

An accompanying editorial (appearing in CA:) by Otis W. Brawley, M.D., chief medical officer of the American Cancer Society, says about 2.6 million of the 7.6 million cancer deaths that occurred in 2008, or about 7300 cancer deaths per day, were potentially avoidable through the prevention of known risk factors, including tobacco use, dietary factors, certain infections, and alcohol use. "The worldwide application of existing cancer control knowledge according to the capacity and economic development of countries or regions could lead to the prevention of even more cancer deaths in the next 2 to 3 decades," writes Dr. Brawley. "In order to achieve this, however, national and international public health agencies, governments, donors, and the private sectors must play major roles in the development and implementation of national or regional cancer control programs worldwide."

A comparison of cancer rates reveals differences in cancer causation between economically developed and economically developing countries. In economically developed countries, the three most commonly diagnosed cancers in 2008 were prostate, lung, and colorectal cancers in men and breast, colorectal, and lung cancers in women. In economically developing countries, cancers of the lung, stomach, and liver were most frequently diagnosed in men while breast, cervical, and lung cancers were the most commonly diagnosed in women. Two of the three leading cancers in men (stomach and liver) and one of the three leading cancers in women (cervix) in developing countries are related to infection. Overall, about one in four cancers in developing countries are related to infection compared to fewer than one in ten in developed countries.

The report also outlines shifts in cancer trends that point to the increasing impact that unhealthy behaviors are beginning to have in developing countries. While male lung cancer death rates are decreasing in most Western countries, they are increasing in China and several other countries in Asia and Africa where the tobacco epidemic is in earlier stages and smoking prevalence has not begun to drop, or even continues to increase. Lung cancer rates in women, which have plateaued in the US, are also increasing in many countries, notably in Spain, France, Belgium, and the Netherlands, where rates are increasing among younger women suggesting that lung cancer in females in these countries will likely increase for several decades barring major interventions.

Breast cancer is now the leading cause of cancer death among females in economically developing countries, a shift from previous decades during which cervical cancer was the most common cause of cancer death. Colorectal cancer incidence rates, which have been decreasing in the US, are rapidly increasing in several countries historically at low risk, including Spain and a number of countries within Eastern Asia and Eastern Europe.

Special Section: Cancer in Africa

Global Cancer Facts & Figures 2nd edition includes a special section on cancer in Africa, where the disease is an emerging public health problem. According to IARC, about 681,000 new cancer cases and 512,400 cancer deaths occurred in 2008 in Africa. These numbers are projected to nearly double (1.28 million new cancer cases and 970,000 cancer deaths) by 2030 due to the aging and growth of the population, with the potential to be even higher due to the adoption of behaviors and lifestyles associated with economic development and urbanization such as smoking, unhealthy diet, and physical inactivity.

The report says despite this growing burden, cancer continues to receive low public health priority in Africa, largely because of limited resources and other pressing public health problems, including communicable diseases such as AIDS/HIV infection, malaria, and tuberculosis.

Cancers related to infectious agents (cervix, liver, Kaposi sarcoma, urinary bladder) are among the dominant forms of cancer in Africa. In 2008, cervical cancer accounted for 21 percent of the total newly diagnosed cancers in females and liver cancer accounted for 11 percent of the total cancer cases in males.

A majority of cancers in Africa are thought to be diagnosed at advanced stage of the disease largely because of lack of screening and early detection services as well as limited awareness of the early signs and symptoms of cancers among the public and health care providers. Stigma associated with a diagnosis of cancer also plays a role in late stage presentation in most parts of Africa.

Survival after a diagnosis of cancer is much poorer in Africa than in the developed world for most cancer types, especially those cancers affected by screening and treatment. For example, the five-year survival rate for breast cancer is less than 50 percent in The Gambia, Uganda, and Algeria, compared to nearly 90 percent in the United States.

While tobacco use is the most preventable cause of cancer death worldwide, accounting for 20 percent of cancer deaths, it accounts for only about 6 percent of cancer deaths in Africa. The smaller contribution of tobacco use to cancer deaths in Africa reflects the early stage of the tobacco epidemic and low smoking prevalence, especially in women. However, cigarette consumption is increasing in many African countries due to the adoption of behaviors associated with economic growth and increased marketing by tobacco companies. The smoking pattern among teens is even more disturbing. According to the Global Youth Tobacco Survey, in some African countries, the smoking prevalence among boys is higher than that among adults. Although a majority of African countries have ratified the Framework Convention on Tobacco Control, few have implemented or enforced tobacco control programs according to the guidelines.

This September, the United Nations will hold a high-level meeting to develop a global response to the growing threat of non-communicable diseases, including cancer, heart disease, and diabetes. This meeting, supported by the United States government, is only the second meeting the United Nations has held on a global health issue.

Provided by American Cancer Society

Obesity has doubled since 1980, major global analysis of risk factors reveals

The worldwide prevalence of obesity has nearly doubled since 1980, according to a major study on how three important heart disease risk factors have changed across the world over the last three decades. The study, published today in three papers in the Lancet, looked at all available global data to assess how body mass index, blood pressure and cholesterol changed between 1980 and 2008.

05 feb 2011-- The study shows that in 2008, more than one in ten of the world's adult population was obese, with women more likely to be obese than men. An estimated 205 million men and 297 million adult women were obese - a total of more than half a billion adults worldwide.

The proportion of the world's population with high blood pressure, or uncontrolled hypertension, fell modestly between 1980 and 2008. However, because of population growth and ageing, the number of people with uncontrolled hypertension rose from 600 million in 1980 to nearly 1 billion in 2008. High-income countries achieved large reductions in uncontrolled hypertension, with the most impressive progress seen in women in Australasia and men in North America. Uncontrolled hypertension is defined as a systolic blood pressure higher than 140 mmHg or diastolic blood pressure higher than 90 mmHg.

Average levels of total blood cholesterol fell in Western countries of North America, Australasia and Europe, but increased in East and Southeast Asia and the Pacific region.

Professor Majid Ezzati, the senior author of the study from the School of Public Health at Imperial College London, said: "Our results show that overweight and obesity, high blood pressure and high cholesterol are no longer Western problems or problems of wealthy nations. Their presence has shifted towards low and middle income countries, making them global problems."

Beyond global trends, the studies reveal how different countries compare in terms of each risk factor. The results show that:

BMI:

• In 2008, 9.8 per cent of men and 13.8 per cent of women in the world were obese (with a BMI above 30 kg/m2), compared with 4.8 per cent for men and 7.9 per cent for women in 1980.
  
• Pacific island nations have the highest average BMI in the world, reaching 34-35 kg/m2, up to 70 per cent higher than some countries in Southeast Asia and sub-Saharan Africa.
  
• Among high income countries, USA has the single highest BMI (over 28 kg/m2 for men and women), followed by New Zealand. Japan has the lowest BMI (about 22 kg/m2 for women and 24 kg/m2 for men), followed by Singapore.
  
• Among high-income countries, between 1980 and 2008, BMI rose most in USA (by more than 1 kg/m2/decade), followed by New Zealand and Australia for women and followed by UK and Australia for men. Women in a few Western European countries had virtually no rise in BMI.
  
• The UK has the sixth highest BMI in Europe for women and ninth highest for men (both around 27 kg/m2).
  
• Turkish women and Czech men have the highest BMI in Europe (both around 28 kg/m2). Swiss women had the lowest BMI in Europe (around 24 kg/m²).

Blood pressure:

• Systolic blood pressure levels are highest in Baltic and East and West African countries, reaching 135 mmHg for women and 138 mmHg for men. These levels were seen in some Western European countries in the 1980s before their impressive declines.
  
• South Korea, Cambodia, Australia, Canada and USA had some of the lowest blood pressures for both men and women, below 120 mmHg for women and below 125 mmHg for men.
  
• Among high income countries, Portugal, Finland and Norway have the highest blood pressure.
  
• Men had higher blood pressure than women in most world regions.

Cholesterol:

• Western European countries like Greenland, Iceland, Andorra, and Germany have the highest cholesterol levels in the world, with mean serum total cholesterols of around 5.5 mmol/L.
  
• African countries have the lowest cholesterol, some as low as 4 mmol/L.
  
• Among western high-income countries, Greece has the lowest cholesterol for both men and women (below 5 mmol/L). USA, Canada, and Sweden also had low cholesterol.
  
• The UK's cholesterol is ninth highest in the world, slightly below 5.5 mmol/L.

The review was carried out by an international collaboration of researchers, led by Professor Majid Ezzati from Imperial College London and co-led by Dr. Goodarz Danaei from the Harvard School of Public Health, in collaboration with The World Health Organization and a number of other institutions.

Professor Ezzati added: "It's heartening that many countries have successfully reduced blood pressure and cholesterol despite rising BMI. Improved screening and treatment probably helped to lower these risk factors in high-income countries, as did using less salt and healthier, unsaturated fats.

"The findings are an opportunity to implement policies that lead to healthier diets, especially lower salt intake, at all levels of economic development, as well as looking at how we improve detection and control through the primary healthcare system. Policies and targets for cardiovascular risk factors should get special attention at the High-level Meeting of the United Nations General Assembly on Non-Communicable Diseases in September 2011."

Dr. Goodarz Danaei, from the Harvard School of Public Health, said: "This is the first time that anyone has tried to estimate trends in these major risk factors in every country in the world. The amount of data we collected is unprecedented and vast, and allows us to draw robust conclusions."

Dr. Gretchen Stevens, from the World Health Organization, said: "Our study helps track the obesity problem in individual countries and regions. We know that changes in diet and in physical activity have contributed to the worldwide rise in obesity, but it remains unclear which policies would effectively reduce obesity. We need to identify, implement, and rigorously evaluate policy interventions aimed at reversing the trends, or limiting their harmful effects."

Provided by Imperial College London

Metabolic syndrome linked to memory loss in older people

Older people with larger waistlines, high blood pressure and other risk factors that make up metabolic syndrome may be at a higher risk for memory loss, according to a study published in the February 2, 2011, online issue of Neurology, the medical journal of the American Academy of Neurology.

04 feb 2011--Metabolic syndrome was defined as having three or more of the following risk factors: high blood pressure, excess belly fat, higher than normal triglycerides (a type of fat found in the blood), high blood sugar and low high-density lipoprotein (HDL) cholesterol, or "good" cholesterol. Metabolic syndrome has also been tied to increased risk of heart attack.

For the study, 7,087 people age 65 and older from three French cities were tested for metabolic syndrome. A total of 16 percent of the participants had metabolic syndrome. Participants were given a series of memory and cognitive function tests two and four years later. The tests included a memory test, a test of visual working memory and a test of word fluency.

Researchers found that people who had metabolic syndrome were 20 percent more likely to have cognitive decline on the memory test than those who did not have metabolic syndrome. Those with metabolic syndrome also were 13 percent more likely to have cognitive decline on the visual working memory test compared to those who did not have the syndrome. Specifically, higher triglycerides and low HDL cholesterol were linked to poorer memory scores; diabetes, but not higher fasting blood sugar, was linked to poorer visual working memory and word fluency scores.

"Our study sheds new light on how metabolic syndrome and the individual factors of the disease may affect cognitive health," said study author Christelle Raffaitin, MD, of the French National Institute of Health Research in Bordeaux, France. "Our results suggest that management of metabolic syndrome may help slow down age-related memory loss, or delay the onset of dementia."

Provided by American Academy of Neurology

Scientists find 5 new Parkinson's genes

Scientists have identified five new genes linked to Parkinson's disease in a large genetic analysis of the illness, according to a new study. After reviewing nearly 8 million possible genetic mutations, researchers pinpointed five genes connected to Parkinson's disease. Previously, six other genes were identified, and experts say there is now increasing proof the degenerative disease is sparked by peoples' genes.

03 feb 2011--The discovery doesn't mean there are any new treatments just yet, but experts are optimistic they are getting closer.

"The major common genetic variants for Parkinson's have been found," said Nick Wood, a professor at the Institute of Neurology at University College London, one of the researchers who led the study. "We haven't put together all the pieces of the puzzle yet, but we're not that far off," he said. He predicted a diagnostic test might be ready within a few years.

Until recently, scientists hadn't been sure what caused Parkinson's disease, but assumed environmental factors such as exposure to chemicals or past head injuries were largely to blame.

Scientists analyzed genetic samples from more than 12,000 people with Parkinson's disease and more than 21,000 from the general population in Europe and the U.S. They found people with the highest number of mutations in the 11 genes linked to Parkinson's were two-and-a-half times more likely to develop the disease than people who had the least amount of mutations.

The average person has a 2.5 percent chance of developing Parkinson's disease in their lifetime, and the risk for people whose close relatives have the illness is about six percent.

The research was paid for by the Wellcome Trust, the National Institute of Aging and the U.S. Department of Defense. It was published online Wednesday in the medical journal Lancet.

Parkinson's is a degenerative brain disease that strikes when brain cells don't make enough of the chemical dopamine. That leads to symptoms including tremors, rigidity and slowness of movement. There are limited treatments and no cure for the disease. It mostly affects people over 50, though younger people, including actor Michael J. Fox, sometimes develop the disease.

Experts said Parkinson's disease was likely the result of a complex interaction between genetics and environmental risk factors.

In an accompanying commentary, scientists said identifying Parkinson's genes could help explain what triggers the disease and one day lead to new treatments.

"There is good reason for optimism that these advances will be translated into direct benefits for our patients," wrote Christine Klein and Andreas Ziegler of the University of Lubeck in Germany.

More information:
http://www.lancet.com

http://www.parkinsons.org.uk

Study predicts risk of memory loss in healthy, older adults

The combined results of a genetic blood test and a five-minute functional MRI successfully classified more than three-quarters of healthy older adults, many of whom were destined to develop cognitive decline within 18 months of testing.

02 feb 2011--John Woodard, Ph.D., associate professor of psychology in the College of Liberal Arts and Sciences and Institute of Gerontology at Wayne State University, is lead author of "Predicting Cognitive Decline in Healthy Older Adults Using fMRI" published in the Journal of Alzheimer's Disease (vol. 21, no. 3).

"No one had studied these combinations of tests in such a large sample," Woodard said. The results have strong implications for determining who is most likely to benefit from preventive Alzheimer's disease treatments.

Woodard and his colleagues performed five tests on 78 healthy elders: a structural MRI (sMRI) that measures the size of the hippocampal region of the brain; a functional MRI (fMRI) that shows how the brain is activated during mental tasks; a blood test that identifies the APOE ε4 allele (a known genetic marker for Alzheimer's disease); and two standard neuropsychological tests that measure mood and ability.

The most effective combination of tests to predict near-term cognitive decline was the fMRI and the APOE ε4 test. The APOE ε4 allele alone correctly classified 61.5 percent of participants, but the combination of the ε4 allele and low activity on the fMRI test correctly classified 78.9 percent of participants, including 35 percent who showed significant cognitive decline 18 months post-testing.

Age, years of education, gender and family history of dementia were not accurate predictors of future cognitive decline. Dr. Woodard and his colleagues also found that persons with larger hippocampal volume, greater functional brain activity and no APOE ε4 allele were less likely to demonstrate cognitive decline over the following 18 months.

The APOE and fMRI tests that combined as the best predictors are readily available, not time-consuming, and don't require special skills or effort on the part of the participant.

"Use of these tests could play a major role in development of medications for prevention of Alzheimer's and other dementias," Woodard said. "If we can intervene before people become symptomatic, we might be able to slow the progression of the disease or eliminate it altogether."

Alzheimer's is age-correlated; the older the person, the greater the likelihood the person will display symptoms.

"If we could delay the onset of Alzheimer's disease by five years, we could cut the number of new cases in half," Dr. Woodard said. "If we could delay the onset of Alzheimer's disease by 10 years, we could potentially eliminate the disease completely."

More information: The complete study is available at http://www.j-alz.c … vol21-3.html

Provided by Wayne State University

U.S. Dietary Guidelines Recommend Lower Salt Intake

New guidelines advise reducing salt and saturated fat intake, avoiding sugary beverages

01 feb 2011-- The seventh edition of the U.S. Department of Agriculture's Dietary Guidelines for Americans was released today, and it calls for Americans to limit their daily sodium intake to less than 2,300 mg, with individuals 51 years of age and older, all blacks, and those with high blood pressure, diabetes, or chronic kidney disease advised to limit their sodium intake to 1,500 mg or less.

The guidelines also recommend that no more than 10 percent of calories should come from saturated fat, which should be replaced with monounsaturated fats or polyunsaturated fatty acids. The guidelines also state that Americans should eat more lean meats and poultry, legumes, nuts, and seeds, as well as fat-free or 1 percent milk. In addition, Americans should avoid added sugars, refined grains, and solid fats as well as consume less than 300 mg per day of cholesterol, according to the guidelines.

Americans are advised to avoid trans fatty acids and consume alcohol in moderation, which means one alcoholic beverage or less for women per day and two drinks for men. Individuals should also drink water instead of sugary sodas or other sweetened beverages. Also, according to the guidelines, nutrients should come from eating nutritious food rather than taking nutritional supplements and Americans should consume more fruits, vegetables, and whole grains to get more needed nutrients.

"Helping Americans incorporate these guidelines into their everyday lives is important to improving the overall health of the American people," Kathleen Sebelius, secretary of the U.S. Department of Health and Human Services, said in a statement. "The new Dietary Guidelines provide concrete action steps to help people live healthier, more physically active and longer lives."

More Information

Moderate aerobic exercise in older adults shown to modify brain hippocampus, improve memory

A new study shows that one year of moderate physical exercise can increase the size of the brain's hippocampus in older adults, leading to an improvement in spatial memory.

01 feb 2011--The project—conducted by researchers at the University of Pittsburgh, University of Illinois, Rice University, and Ohio State University—is considered the first study of its kind focusing on older adults who are already experiencing atrophy of the hippocampus, the brain structure involved in all forms of memory formation. The study, funded through the National Institute on Aging, appears in the Jan. 31 Proceedings of the National Academy of Sciences (PNAS).

The scientists recruited 120 sedentary older people without dementia and randomly placed them in one of two groups—those who began an exercise regimen of walking around a track for 40 minutes a day, three days a week, or those limited to stretching and toning exercises. Magnetic resonance images were collected before the intervention, after six months, and at the end of the one-year study.

The aerobic exercise group demonstrated an increase in volume of the left and right hippocampus of 2.12 percent and 1.97 percent, respectively. The same regions of the brain in those who did stretching exercises decreased in volume by 1.40 and 1.43 percent, respectively.

Spatial memory tests were conducted for all participants at the three intervals. Those in the aerobic exercise group showed improved memory function, when measured against their performance at the start of the study, an improvement associated with the increased size of the hippocampus. The authors also examined several biomarkers associated with brain health, including brain-derived neurotrophic factor (BDNF), a small molecule that is involved in learning and memory. They found that the increases in hippocampal size were associated with increased amounts of BDNF.

"We think of the atrophy of the hippocampus in later life as almost inevitable," said Kirk Erickson, professor of psychology at the University of Pittsburgh and the paper's lead author. "But we've shown that even moderate exercise for one year can increase the size of that structure. The brain at that stage remains modifiable."

"The results of our study are particularly interesting in that they suggest that even modest amounts of exercise by sedentary older adults can lead to substantial improvements in memory and brain health," said Art Kramer, director of the Beckman Institute at the University of Illinois and the senior author.

"Such improvements have important implications for the health of our citizens and the expanding population of older adults worldwide."

Provided by University of Illinois at Urbana-Champaign

Mindfulness meditation training changes brain structure in 8 weeks

31 jan 2011-- Participating in an 8-week mindfulness meditation program appears to make measurable changes in brain regions associated with memory, sense of self, empathy and stress. In a study that will appear in the January 30 issue of Psychiatry Research: Neuroimaging, a team led by Massachusetts General Hospital (MGH) researchers report the results of their study, the first to document meditation-produced changes over time in the brain's grey matter.

"Although the practice of meditation is associated with a sense of peacefulness and physical relaxation, practitioners have long claimed that meditation also provides cognitive and psychological benefits that persist throughout the day," says Sara Lazar, PhD, of the MGH Psychiatric Neuroimaging Research Program, the study's senior author. "This study demonstrates that changes in brain structure may underlie some of these reported improvements and that people are not just feeling better because they are spending time relaxing."

Previous studies from Lazar's group and others found structural differences between the brains of experienced mediation practitioners and individuals with no history of meditation, observing thickening of the cerebral cortex in areas associated with attention and emotional integration. But those investigations could not document that those differences were actually produced by meditation.

For the current study, MR images were take of the brain structure of 16 study participants two weeks before and after they took part in the 8-week Mindfulness-Based Stress Reduction (MBSR) Program at the University of Massachusetts Center for Mindfulness. In addition to weekly meetings that included practice of mindfulness meditation – which focuses on nonjudgmental awareness of sensations, feelings and state of mind – participants received audio recordings for guided meditation practice and were asked to keep track of how much time they practiced each day. A set of MR brain images were also taken of a control group of non-meditators over a similar time interval.

Meditation group participants reported spending an average of 27 minutes each day practicing mindfulness exercises, and their responses to a mindfulness questionnaire indicated significant improvements compared with pre-participation responses. The analysis of MR images, which focused on areas where meditation-associated differences were seen in earlier studies, found increased grey-matter density in the hippocampus, known to be important for learning and memory, and in structures associated with self-awareness, compassion and introspection. Participant-reported reductions in stress also were correlated with decreased grey-matter density in the amygdala, which is known to play an important role in anxiety and stress. Although no change was seen in a self-awareness-associated structure called the insula, which had been identified in earlier studies, the authors suggest that longer-term meditation practice might be needed to produce changes in that area. None of these changes were seen in the control group, indicating that they had not resulted merely from the passage of time.

"It is fascinating to see the brain's plasticity and that, by practicing meditation, we can play an active role in changing the brain and can increase our well-being and quality of life." says Britta Hölzel, PhD, first author of the paper and a research fellow at MGH and Giessen University in Germany. "Other studies in different patient populations have shown that meditation can make significant improvements in a variety of symptoms, and we are now investigating the underlying mechanisms in the brain that facilitate this change."

Amishi Jha, PhD, a University of Miami neuroscientist who investigates mindfulness-training's effects on individuals in high-stress situations, says, "These results shed light on the mechanisms of action of mindfulness-based training. They demonstrate that the first-person experience of stress can not only be reduced with an 8-week mindfulness training program but that this experiential change corresponds with structural changes in the amydala, a finding that opens doors to many possibilities for further research on MBSR's potential to protect against stress-related disorders, such as post-traumatic stress disorder." Jha was not one of the study investigators.

More information: Psychiatry Research: Neuroimaging

Provided by Massachusetts General Hospital

Hormone therapy begun at menopause may pose risk for breast cancer

Starting hormone therapy at around the time of menopause is associated with a greater risk of breast cancer compared to starting after a longer gap, according to a study published online Jan. 28 in The Journal of the National Cancer Institute.

In this large, prospectively followed cohort of women, those who started hormone therapy five years or more after menopause had little or no increased risk, regardless of the type of hormone therapy used, how long they used it, and whether they were overweight or obese.

30 jan 2011--Many studies have established that breast cancer incidence increases in users of hormonal therapy, in particular among women who use an estrogen-progestin combination as opposed to estrogen-alone. Few studies have looked at the timing of hormone therapy as a risk factor, although two previous studies suggested the interval between menopause and initiating hormone therapy may influence breast cancer risk.

To investigate this question, Valerie Beral, FRS, of Oxford University and colleagues, used data from the Million Women Study (MWS) in the UK. The researchers estimated the adjusted relative risks of breast cancer in hormone therapy users and past users compared to non-users in 1.13 million women in the study. They also compared women on different types of hormone therapy.

They found that women starting hormone therapy at the time of menopause were at greater risk of breast cancer than those starting it later. They write, "A new finding of this study, which has been little investigated previously, is that the interval between menopause and starting hormonal therapy has a substantial effect on breast cancer risk."

Two previous studies have suggested this association but only in certain subgroups. "In this large study, we found greater risks of breast cancer if hormonal therapy use began either before or soon after menopause than after a longer gap; and this pattern of risk was seen across different types of hormonal therapy, among women who used hormonal therapy for either short of long durations, and also in lean and in overweight and obese women."

In an accompanying editorial, Rowan T. Chlebowski, M.D., Ph.D., of Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center and Garnet Anderson from the Fred Hutchinson Cancer Research Center note the study provides substantial support for similar findings from the Women's Health Initiative (WHI) in the U.S. They add that the similarities between the patterns of breast cancer risk in these two large studies increase the likely validity of the results, especially since the methodologies of the two studies were quite different.

The editorialists also discuss discrepancies in the two studies' findings regarding the risk of estrogen-only hormone therapy; the WHI found little risk associated with estrogen alone while the MWS found a statistically significant increased risk, except in overweight and obese women. They conclude that "the question of the effect of estrogen-only formulation use on breast cancer risk in postmenopausal women, even with longer-term hormone use, still stands unanswered."

Provided by Journal of the National Cancer Institute

Adult ADHD Linked to Lewy Body Dementia

Patients with Lewy body dementia more likely to have history of attention deficit in adulthood

29 jan 2011-- Adults with symptoms of attention-deficit and hyperactivity disorder (ADHD) may be at increased risk of developing dementia with Lewy bodies (DLB), according to a study published in the January issue of the European Journal of Neurology.

Angel Golimstok, M.D., of the Hospital Italiano Buenos Aires in Argentina, and colleagues investigated the link between ADHD symptoms in adults and the subsequent development of DLB. The frequency of ADHD symptoms during adult life was evaluated in 109 patients with DLB, 251 patients with Alzheimer's disease, and 149 controls, between 2000 and 2005.

The researchers found the prevalence of ADHD symptoms to be significantly higher in DLB cases compared to either the control group or the Alzheimer's disease group. The frequency of preceding ADHD symptoms in DLB cases was 47.8 percent, compared with 15.2 percent in those with Alzheimer's disease and 15.1 percent in the control group.

"The association between ADHD symptoms and DLB that we observed may be explained by a common neurotransmitter pathway dysfunction in both entities. We hypothesized that a common process is involved in both illnesses: ADHD in the initial state of that dysfunction that progresses to DLB in senescence," the authors write.

Abstract

Yearly mammograms from age 40 save 71 percent more lives, study shows

A new study questions the controversial U.S. Preventative Service Task Force recommendations for breast cancer screening, with data that shows starting at a younger age and screening more frequently will result in more lives saved.

29 jan 2011--The study analyzed the same data looked at by the task force, which issued its guidelines on mammography screening in November 2009. The study authors compared the task force's recommendations for screening every other year in women 50-74 to American Cancer Society guidelines of screening every year in women 40-84.

The study was conducted by R. Edward Hendrick, Ph.D., clinical professor of radiology at the University of Colorado School of Medicine, and Mark Helvie, M.D., director of breast imaging at the University of Michigan Comprehensive Cancer Center. It appears in the February issue of the American Journal of Roentgenology.

Hendrick and Helvie used six model scenarios of screening mammography created by the Cancer Intervention and Surveillance Modeling Network. This is the same modeling data the task force considered. The authors compared task force guidelines to American Cancer Society guidelines.

They found that if women begin yearly mammograms at age 40, it reduces breast cancer deaths by 40 percent. When screening begins at 50 and occurs every other year, it reduces breast cancer deaths 23 percent.

The difference between these two screening strategies comes down to 71 percent more lives saved with yearly screening beginning at 40.

"Task force guidelines have created confusion among women, leading some to forego mammography altogether. Mammography is one of the few screening tools that has been proven to save lives and our analysis shows that for maximum survival, annual screening beginning at 40 is best. This data gives women more information to make an informed choice about the screening schedule that's best for them," says Helvie, professor of radiology at the U-M Medical School.

As part of their recommendation, the task force emphasized the potential harms mammography can cause – including pain during the screening exam and anxiety from false-positives, which can lead to additional imaging or biopsy.

The study authors found that on average women ages 40-49 who are screened annually will have a false-positive mammogram once every 10 years. They will get asked back for more tests once every 12 years and will undergo a false-positive biopsy once every 149 years.

"The task force overemphasized potential harms of screening mammography, while ignoring the proven statistically significant benefit of annual screening mammography starting at age 40," Hendrick says. "In addition, the panel ignored more recent data from screening programs in Sweden and Canada showing that 40 percent of breast cancer deaths are averted in women who get regular screening mammography. Our modeling results agree completely with these screening program results in terms of the large number of women lives saved by regular screening mammography."

More information: American Journal of Roentgenology, Vol. 196, W112-W116, February 2011

Provided by University of Michigan Health System

Diabetes Prevalence Reaches 26 Million in United States

8.3 percent of U.S. population now affected, and 35 percent of adults have prediabetes

28 jan 2011 -- Nearly 26 million people in the United States have diabetes, and 79 million U.S. adults are estimated to have prediabetes, according to new estimates released by the U.S. Centers for Disease Control and Prevention.

Members of the CDC collected data from their own surveys, the Indian Health Service's National Patient Information Reporting System, the U.S. Renal Data System of the National Institutes of Health, the U.S. Census Bureau, and published studies to compile a fact sheet representing the current status of diabetes in the United States.

The researchers note that, in 2011, diabetes affects 8.3 percent of all Americans, or almost 26 million people, and that prediabetes affects 35 percent (79 million) of adults aged 20 and older. The CDC estimates that 27 percent of individuals with diabetes, or 7 million people, do not know they have it. In 2008, the agency estimated that 23.6 million Americans -- 7.8 percent of the population -- had diabetes and that 57 million adults had prediabetes. The CDC notes that the 2011 estimates have increased because more people are developing diabetes, more people are living longer with the disease, and hemoglobin A1c is now used as a diagnostic test and was incorporated into national prevalence calculations for the first time.

"These distressing numbers show how important it is to prevent type 2 diabetes and to help those who have diabetes manage the disease to prevent serious complications such as kidney failure and blindness," Ann Albright, Ph.D., R.D., director of CDC's Division of Diabetes Translation, said in a statement. "We know that a structured lifestyle program that includes losing weight and increasing physical activity can prevent or delay type 2 diabetes."

Little-known growth factor enhances memory, prevents forgetting in rats

A naturally occurring growth factor significantly boosted retention and prevented forgetting of a fear memory when injected into rats' memory circuitry during time-limited windows when memories become fragile and changeable. In the study funded by the National Institutes of Health, animals treated with insulin-like growth factor (IGF-II) excelled at remembering to avoid a location where they had previously experienced a mild shock.

28 jan 2011--"To our knowledge, this is the first demonstration of potent memory enhancement via a naturally occurring factor that readily passes through the blood-brain barrier – and thus may hold promise for treatment development," explained Cristina Alberini, Ph.D., of Mount Sinai School of Medicine, New York, a grantee of the NIH's National Institute of Mental Health (NIMH).

Alberini and colleagues say IGF-II could become a potential drug target for boosting memory. They report on their discovery in the Jan. 27, 2011 issue of Nature.

"As we learn more about such mechanisms of fear memory formation and extinction, we hope to apply this knowledge to address clinical problems, including post-traumatic stress disorder," said NIMH Director Thomas R. Insel, M.D.

The staying power of a memory depends on the synthesis of new proteins and structural changes in the connections between brain cells. These memory-strengthening changes occur within time-limited windows right after learning, when memories undergo consolidation, and also right after a memory is retrieved, a process called reconsolidation.

Hints from other studies led the researchers to suspect that IGF-II plays a role in these processes within the brain's memory center, the hippocampus, where it is relatively highly concentrated. The little-known growth factor is part of the brain's machinery for tissue repair and regeneration; it is important during development and declines with age.

To find out how it might work in memory, Alberini's team employed a standard test of fear memory called inhibitory avoidance training. They tracked the movement of rats in an environment where the animals learned to associate a dark area with mild foot shocks. The more an animal avoided the dark area, the better its fear memory.

This kind of learning boosted the expression of naturally occurring IGF-II in the hippocampus. So the researchers injected synthetic IGF-II directly into the hippocampus during windows of consolidation or reconsolidation, when memories are malleable. Remarkably, the rats' memory markedly improved – with the effects lasting at least a few weeks. An examination of the animals' brains revealed that IGF-II had strengthened the cellular connections and mechanisms underlying long-term memory – a process called long-term potentiation.

So IGF-II both strengthened a memory and delayed its normal decay – forgetting, noted Alberini.

The researchers had previously discovered that the fragility induced by memory retrieval requires new protein synthesis in the brain's fear area, the amygdala – but only if the memory is less than two weeks old. In the new study, they found that memory enhancement triggered by IGF-II during this reconsolidation window depended on new protein synthesis in the hippocampus during the same time period. They suggest that these time-limited effects might be explained by a gradual shift in the site where a memory is stored as it grows older, from the hippocampus to the brain's outer mantle, or cortex.

The study showed that the growth factor works through its own – also little known – IGF-II receptor and depends on activation of an enzyme (GSK3 beta), and AMPA receptors for the chemical messenger glutamate, both of which are implicated in memory. Evidence suggests that rather than activating new neurons, it appears to work through already activated connections between cells – or synapses – that are regulated by the enzyme and receptor.

Among future directions, researchers could explore whether IGF-II might enhance other types of memory, such as extinction learning, in which a fear memory is replaced by a memory of safety, said Alberini. If so, it might provide clues to new treatments for anxiety disorders like PTSD.

Provided by National Institutes of Health

Cost to treat heart disease in United States will triple by 2030

The cost to treat heart disease in the United States will triple by 2030, according to a policy statement published in Circulation: Journal of the American Heart Association.

27 jan 2011--"Despite the successes in reducing and treating heart disease over the last half century, even if we just maintain our current rates, we will have an enormous financial burden on top of the disease itself," said Paul Heidenreich, M.D., chair of the American Heart Association expert panel issuing the statement.

The panel estimated future medical costs based on the current rates of disease and used Census data to adjust for anticipated population shifts in age and race. The rigorous methods they devised didn't double count costs for patients with multiple heart conditions.

"These estimates don't assume that we will continue to make new discoveries to reduce heart disease," Heidenreich said. "If our ability to prevent and treat heart disease stays where we are right now, costs will triple in 20 years just through demographic changes in the population."

The panel said effective prevention strategies are needed to limit the growing burden of cardiovascular disease — the leading cause of death in the United States that accounts for 17 percent of overall national health expenditures.

"Unhealthy behaviors and unhealthy environments have contributed to a tidal wave of risk factors among many Americans," said Nancy Brown, American Heart Association CEO. "Early intervention and evidence-based public policies are absolute musts to significantly reduce alarming rates of obesity, hypertension, tobacco use and cholesterol levels."

Currently, 1 in 3 Americans (36.9 percent) have some form of heart disease, including high blood pressure, coronary heart disease, heart failure, stroke and other conditions. By 2030, approximately 116 million people in the United States (40.5 percent) will have some form of cardiovascular disease, the panel said. The largest increases are anticipated in stroke (up 24.9 percent) and heart failure (up 25 percent).

Between 2010-30, the cost of medical care for heart disease (in 2008 dollar values) will rise from $273 billion to $818 billion, the authors predicted. "We were all surprised at the remarkable increase in costs that are expected in the next two decades," Heidenreich said. "We need to continue to invest resources in the prevention of disease, the treatment of risk factors and early treatment of existing disease to reduce that burden."

Provided by American Heart Association