What causes hangovers, blackouts and 'hangxiety'? Everything you need to know about alcohol these holidays

by Nicole Lee and Brigid Clancy, The Conversation

There’s no way to cure a hangover, even with ‘hair of the dog’. Credit: Louis Hansel

With the holiday season well underway and New Year's Eve approaching, you might find yourself drinking more alcohol than usual.

31 dec 2019--So what actually happens to our body as we drink alcohol and wake up with a hangover?

What about memory blackouts and "hangxiety", when you can't remember what happened the night before or wake up with an awful feeling of anxiety?

Let's look at what the science says—and bust some long-standing myths.

What happens when you drink alcohol?

It doesn't matter what type of alcohol you drink—or even whether you mix drinks—the effects are basically the same with the same amount of alcohol.

When you drink alcohol it goes into the stomach and passes into the small intestine where it's quickly absorbed into the bloodstream.

If you have eaten something, it slows the absorption of alcohol so you don't get drunk so quickly. That's why it's a good idea to eat before and during drinking.

It takes your body about an hour to metabolise 10g, or one standard drink, of alcohol.

(There are calculators that help you estimate your blood alcohol level but everybody breaks down alcohol at a different rate. So these calculators should only be used as a guide.)

What causes memory blackouts?

We all have that friend who has woken up after a big night out and not been able to remember half the night. That's a "blackout".

It's different to "passing out"—you're still conscious and able to carry out conversation, you just can't remember it later.

The more alcohol you drink and the faster you drink it, the more likely you are to experience blackouts.

Once alcohol in your blood reaches a certain level, your brain simply stops forming new memories. If you think of your brain like a filing cabinet, files are going straight to the bin, so when you later try to look for them they are lost.

How do I sober up?

If you've had too much, there's no way to sober up quickly. The only thing that can sober you up is time, so that the alcohol can be eliminated from your body.

The caffeine in coffee may make you feel more awake, but it doesn't help break down alcohol. You will be just as intoxicated and impaired, even if you feel a little less drunk.

The same goes for cold showers, exercise, sweating it out, drinking water, and getting fresh air. These things might help you feel more alert, but they have no impact on your blood alcohol concentration or on the effects of alcohol.

What causes hangovers?

Researchers haven't identified one single cause of hangovers, but there are a few possible culprits.

Alcohol is a diuretic, so it makes you urinate more often, which can lead to dehydration. This is especially the case if you're in a hot, sweaty venue or dancing a lot. Dehydration can make you feel dizzy, sleepy and lethargic.

Alcohol can irritate your stomach lining, causing vomiting and diarrhoea, and electrolyte imbalance.

An imbalance of electrolytes (the minerals our body need to function properly) can make you feel tired, nauseated, and cause muscle weakness and cramps.

Too much alcohol can cause your blood vessels to dilate (expand), causing a headache. Electrolyte imbalance and dehydration can also contribute to that thumping head the next morning.

Alcohol also interferes with glucose production, resulting in low blood sugar. Not producing enough glucose can leave you feeling sluggish and weak.

Alcohol also disrupts sleep. It can make you feel sleepy at first but it interrupts the circadian cycle, sleep rhythms and REM (rapid eye movement) sleep, so later in the night you might wake up.

It can stop you from getting the quality of sleep you need to wake feeling refreshed.

Why 'hair of the dog' doesn't work

There's no way to cure a hangover, even with "hair of the dog" (having a drink the morning after). But drinking the next morning might delay the onset of symptoms, and therefore make you feel better temporarily.

Your body needs time to rest, metabolise the alcohol you have already had, and repair any damage from a heavy night of drinking. So it's not a good idea.

If you drink regularly and you find yourself needing a drink the next morning, this may be a sign of alcohol dependence and you should talk with your GP.

Suffering from hangxiety?

Alcohol has many effects on the brain, including that warm, relaxed feeling after a couple of drinks. But if you've ever felt unusually anxious after a big night out you might have experienced "hangxiety".

Over a night of drinking, alcohol stimulates the production of a chemical in the brain called GABA, which calms the brain, and blocks the production of glutamate, a chemical associated with anxiety. This combination is why you feel cheerful and relaxed on a night out.

Your brain likes to be in balance, so in response to drinking it produces more glutamate and blocks GABA. Cue that shaky feeling of anxious dread the next morning.

What can you do if you wake up with hangxiety?

To ease some of the symptoms, try some breathing exercises, some mindfulness practices and be gentle with yourself.

There are also effective treatments for anxiety available that can help. Talk to your GP or check out some resources online.

If you're already an anxious person, drinking alcohol may help you feel more relaxed in a social situation, but there is an even greater risk that you will feel anxiety the next day.

Prevention is better than a cure

If you choose to drink this holiday season, the best way to avoid hangovers, hangxiety, and blackouts is to stick within recommended limits.

The new draft Australian alcohol guidelines recommend no more than ten standard drinks a week and no more than four standard drinks on any one day.

(If you want to check what a standard drink looks like, use this handy reference.)

As well as eating to slow the absorption of alcohol, and drinking water in between alcoholic drinks to reduce the negative effects, you can also:

• set your limits early. Decide before you start the night how much you want to drink, then stick to it
• count your drinks and avoid shouts
• slow down, take sips rather than gulps and avoid having shots.

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Provided by The Conversation 

Intermittent fasting: live 'fast,' live longer?

by Johns Hopkins University School of Medicine

The Benefits of Intermittent Fasting. Credit: Johns Hopkins Medicine

For many people, the New Year is a time to adopt new habits as a renewed commitment to personal health. Newly enthusiastic fitness buffs pack into gyms and grocery stores are filled with shoppers eager to try out new diets.

29 dec 2019--But, does scientific evidence support the claims made for these diets? In a review article published in the Dec. 26 issue of The New England Journal of Medicine, Johns Hopkins Medicine neuroscientist Mark Mattson, Ph.D., concludes that intermittent fasting does.

Mattson, who has studied the health impact of intermittent fasting for 25 years, and adopted it himself about 20 years ago, writes that "intermittent fasting could be part of a healthy lifestyle." A professor of neuroscience at the Johns Hopkins University School of Medicine, Mattson says his new article is intended to help clarify the science and clinical applications of intermittent fasting in ways that may help physicians guide patients who want to try it.

Intermittent fasting diets, he says, fall generally into two categories: daily time-restricted feeding, which narrows eating times to 6-8 hours per day, and so-called 5:2 intermittent fasting, in which people limit themselves to one moderate-sized meal two days each week.

An array of animal and some human studies have shown that alternating between times of fasting and eating supports cellular health, probably by triggering an age-old adaptation to periods of food scarcity called metabolic switching. Such a switch occurs when cells use up their stores of rapidly accessible, sugar-based fuel, and begin converting fat into energy in a slower metabolic process.

Mattson says studies have shown that this switch improves blood sugar regulation, increases resistance to stress and suppresses inflammation. Because most Americans eat three meals plus snacks each day, they do not experience the switch, or the suggested benefits.

In the article, Mattson notes that four studies in both animals and people found intermittent fasting also decreased blood pressure, blood lipid levels and resting heart rates.

Evidence is also mounting that intermittent fasting can modify risk factors associated with obesity and diabetes, says Mattson. Two studies at the University Hospital of South Manchester NHS Foundation Trust of 100 overweight women showed that those on the 5:2 intermittent fasting diet lost the same amount of weight as women who restricted calories, but did better on measures of insulin sensitivity and reduced belly fat than those in the calorie-reduction group.

More recently, Mattson says, preliminary studies suggest that intermittent fasting could benefit brain health too. A multicenter clinical trial at the University of Toronto in April found that 220 healthy, nonobese adults who maintained a calorie restricted diet for two years showed signs of improved memory in a battery of cognitive tests. While far more research needs to be done to prove any effects of intermittent fasting on learning and memory, Mattson says if that proof is found, the fasting—or a pharmaceutical equivalent that mimics it—may offer interventions that can stave off neurodegeneration and dementia.

"We are at a transition point where we could soon consider adding information about intermittent fasting to medical school curricula alongside standard advice about healthy diets and exercise," he says.

Mattson acknowledges that researchers do "not fully understand the specific mechanisms of metabolic switching and that "some people are unable or unwilling to adhere" to the fasting regimens. But he argues that with guidance and some patience, most people can incorporate them into their lives. It takes some time for the body to adjust to intermittent fasting, and to get beyond initial hunger pangs and irritability that accompany it. "Patients should be advised that feeling hungry and irritable is common initially and usually passes after two weeks to a month as the body and brain become accustomed to the new habit," Mattson says.

To manage this hurdle, Mattson suggests that physicians advise patients to gradually increase the duration and frequency of the fasting periods over the course of several months, instead of "going cold turkey." As with all lifestyle changes, says Mattson, it's important for physicians to know the science so they can communicate potential benefits, harms and challenges, and offer support.

Hangovers: This is what happens to your body when you've had one too many

by Hal Sosabowski, The Conversation

Credit: Elur/Shutterstock

Having a few drinks at Christmas is, for some people, as much a part of the festive tradition as presents, decorations or carols. So if you find yourself nursing a hangover on Boxing Day, you might be interested to know what's actually going on inside your body and why you feel so bad.

20 dec 2019--We tend to drink because in low doses alcohol is initially a euphoriant, it makes you feel happier. It does this by causing the body to release dopamine and endorphins, chemicals that stimulate the brain's reward system. But, after a while and as you drink more, it ultimately suppresses some brain activity and slows down your heart and breathing.

The effects of the initial intake of any alcohol is the first of many stages of narcosis, the last of which is death. There just happens to be a large window between an effective dose (which has you thinking you are far more witty and handsome than you actually are and, later, running down the street with a traffic cone on your head) and a lethal dose (which has you on a mortuary slab).

Note that even before you arrive at the typical drink drive limit, you might experience excitement, uncoordination, impairment, speech slurring, swaying and loss of inhibition. And yet you'll still legally be able to drive a car. Small amounts of alcohol affect the limbic system in the brain, which result in aggression and the Friday and Saturday night melees common in many town centers.

Alcohol is also a vasodilator, which means it widens blood vessels, diverting blood from the body's core to its extremities. This results in the characteristic flushed cheeks you can get from consuming alcohol and also the red nose often sported by dyed-in-the-wool drinkers.

Initially, drinking alcohol is self-reinforcing. What might seem a good idea initially seems an even better idea after you've had a few. Alcohol is absorbed quicker than most things since some is absorbed in the stomach (rather than the small intestine). It then spreads throughout the body and is distributed to all organs including the brain and the liver, where the body makes a valiant attempt to break down and dispose of the alcohol.

To do this, the liver produces enzymes, small molecules that help either make or break down important molecules. In this case, the enzyme alcohol dehydrogenase breaks down the alcohol (ethanol) into acetaldehyde (ethanal), which is then further broken down into acetic (ethanoic) acid and then to carbon dioxide.

Energy is also released at all stages of the breakdown, which explains why heavy drinkers can sometimes be overweight. In fact, long-term alcoholics often get most of their calories from alcohol and eat very little. This can make them overweight but curiously undernourished because they are consuming empty calories and no vitamins or protein, which can produce a general appearance and feeling of illness.

Why you vomit

The first stage breakdown product, ethanal, is an emetic, which means it makes you want to vomit. As you drink and become more euphoric, your blood ethanol level is being monitored by the area postrema, the part of your brain which checks your blood for things that shouldn't be there. If you eat some food which causes vomiting and diarrhea, it's your postrema that has instructed your body to get rid of the offending comestibles.

Ethanal has the same effect. The postrema works to very fine tolerances, and as soon as your body contains enough ethanal, and the threshold that nature has set is reached, the postrema instructs your stomach to contract and makes you sick. Trying to stop this is like trying to hold back the tide. You may have noticed the very short time between drinking enthusiastically and realizing that it's a question of when, and not if, you are going to vomit.

Disulfiram (Antabuse) is a drug used to treat chronic alcoholism that stops the subsequent breakdown of ethanal after you drink, causing an immediate hangover and explosive vomiting. It's effectively a form of aversion therapy.

Hangover causes

Unfortunately, there's no drug to treat drunkenness itself—or a hangover. Once you are intoxicated you just have to wait it out. The liver can metabolize between 8g and 12g of alcohol in an hour and the only way to become less drunk is to stop drinking so the alcohol can diffuse out of your brain and your liver can complete the breakdown.

Aside from the vomiting, we don't know exactly why we feel so terrible when we're hungover, but it is thought to be another effect of ethanal and congeners, the non-alcoholic chemical clutter that is a by-product of fermentation. These include oils, minerals and other forms of alcohol such as methanol (wood alcohol), which can cause you to go blind in high doses.

Darker drinks have higher amounts of congeners. Red wine also causes a particularly vicious hangover since it contains a vasoconstrictor, which constricts your blood vessels and causes that throbbing headache. Meanwhile, vodka might be more forgiving since "pure" vodka is just alcohol and water.

The only other thing that might help reduce your hangover after a heavy drinking session is a glass of water before bed. Alcohol stops your pituitary gland producing the anti-diuretic hormone vasopressin, which normally restricts urine production. This means you end up losing more water than you take in, causing dehydration that irritates the blood vessels, leading to headaches.

Otherwise, you'll just have to console your post-Christmas blues with roast dinner leftovers and your favorite holiday film.

Provided by The Conversation 

Spine surgery is safe in patients of advanced age

by Journal of Neurosurgery Publishing Group

Credit: CC0 Public Domain

Spine surgeons from seven institutions in Sapporo, Hokkaido, Japan, conducted a multicenter, prospective study of spine surgeries performed in patients 80 years of age and older. Although the overall perioperative complication rate was high—20%, there were no major systemic complications and no deaths in the patients. The surgeons conclude that spine surgery is safe in this age group.

20 dec 2019--Detailed findings of this study can be found in a new article, "Perioperative complications of spine surgery in patients 80 years of age or older: a multicenter prospective cohort study," by Takamasa Watanabe, MD, and colleagues, published today in the Journal of Neurosurgery: Spine.

The world's population is steadily growing older. This can be seen most readily in Japan, where elderly people (ages 65 years and older) currently make up a quarter of the total population; that proportion is expected to reach one-third by 2050. The aging population in other countries is also growing. Along with increased age comes a variety of age-related health problems; degenerative spine diseases constitute a common health problem in older persons.

Spine surgery can improve quality of life in many patients with damaged or deteriorating spinal components. This is true for older patients as well as for younger ones. But what about patients in the upper range of elderly, those 80 years of age or older? Is spine surgery advisable in this group and what risks does it carry?

The authors of this study conducted a prospective multicenter study with two goals: 1) determine what perioperative complications of spine surgery are associated with patients in this advanced-age group and 2) investigate the risk factors for perioperative systemic complications.

Seven spine centers with board-certified spine surgeons participated in the study. The patient group consisted of 270 patients, 80 years or older, who underwent elective spine surgery in 2017. (Patients with tumors, infection, or trauma were not included.)

Perioperative complications were defined as adverse events occurring during surgery or within 30 days postoperatively. Complications were separated into those occurring at the surgical site and those that were systemic.

The total perioperative complication rate in the study was 20% (67 complications in 54 patients). Complications at the surgical site occurred in 22 patients (8.1%), and minor systemic complications (anemia, delirium, or urinary tract infection) occurred in 40 patients (14.8%). No patient experienced a major systemic complication (one that could be potentially life-threatening or lead to prolonged hospitalization), and no patient died. The rate of repeated operations was 4.1%.

To identify risk factors for perioperative complications, the authors examined surgical factors (operative level, number of spinal levels treated, type of surgery, length of surgery, and estimated blood loss) as well as patient demographics (age, sex, and body mass index) and preoperative health status.

Each patient's preoperative health status was determined by using the following measurements: the Charlson Comorbidity Index (predicts survival based on comorbidities); the American Society of Anesthesiologists Physical Status Classification System (used to assess the patient's general condition); the Eastern Cooperative Oncology Group Performance Status (ECOG-PS) (used to evaluate patients' ability to take care of themselves); the presence of sarcopenia (loss of muscle mass and strength); and the Geriatric Nutritional Risk Index (used to evaluate nutritional risk).

Both the univariate and multivariate analyses identified spine surgery involving instrumentation (for example, inclusion of plates and screws), operations lasting more than 180 minutes, and the ECOG-PS (limited activities of daily living) as significant risk factors for minor systemic perioperative complications.

The authors suggest that spine surgeons be aware of these risk factors when preparing for surgery in this advanced-age patient group.

Older age itself, the presence of comorbidities, and being at nutritional risk were not found to be risk factors in this study. In addition, there were no severe complications. On the basis of their findings, the authors conclude that it is safe to perform spine surgery in patients of advanced age.

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More information: Watanabe T, Kanayama M, Takahata M, Oda I, Suda K, Abe Y, Okumura J, Hojo Y, Iwasaki N: Perioperative complications of spine surgery in patients 80 years of age or older: a multicenter prospective cohort study. J Neurosurg Spine, published ahead of print December 17, 2019. DOI: 10.3171/2019.9.SPINE19754

Journal information: Journal of Neurosurgery: Spine 

Research finds that just 14% of people in the world have access to palliative care

by University of Glasgow

Credit: University of Glasgow

Just 14 percent of people in the world population have access to palliative care services that allow people to die with dignity and alleviate their suffering, according to new research led by the University of Glasgow.

20 dec 2019--And more than half of the world's population – mainly in low and middle-income countries – have very poor or non-existent access to palliative care.

The delivery of palliative care is now seen as a global health issue - but the new study shows that palliative care services are lagging behind the rapidly growing need for specialised care that can relieve suffering at the end of life.

Led by Professor David Clark at the University of Glasgow, the study found that only 30 countries from 198 in the world have sophisticated levels of palliative care provision that are fully integrated into the health and social care system, covering just 14 percent of the global population.

Study collaborator Professor Carlos Centeno, of the University of Navarra in Spain, added: "Our research shows how much there is still is to do in this field. It is time to demand from policy-makers greater efforts to improve access to palliative care education and training for professionals and to incorporate palliative care into national health systems."

With an 87 percent increase predicted by 2060 in serious health-related suffering that can be relieved by palliative care services, the study calls for a major review of global policies to promote palliative care.

Study collaborator and Chief Executive of the Worldwide Hospice and Palliative Care Alliance Dr Stephen Connor said: "The 2014 World Health Assembly resolution calling for the strengthening of palliative care in all countries is not being realised and millions of patients and families are suffering unnecessarily due to the slow progress in global palliative care development."

Professor Clark said the research team had significantly improved the methods for conducting this study when compared to its two previous versions, incorporating appropriate indicators of palliative care development drawn from the recent literature and using a more transparent, statistically justified algorithm for the analysis.

"This is the most robust analysis to date of the level of palliative care development in almost all countries of the world. We categorise each country into one of six levels of development, show how many countries are now at each level, and also map these onto the proportions of the global population in each category - revealing that half the global population has little access to specialised palliative care," he added.

Policy-makers, activists and third-party funders involved in palliative care are acutely aware of the limited evidence that exists about development in the field, particularly in low and middle-income countries, said Professor Clark.
The World Health Assembly has endorsed the need for all countries to develop national strategies for palliative care provision. The research team's analysis of 198 countries in 2017 casts some doubt, however, on the effectiveness of recent global strategies.

"It provides powerful evidence for a renewed focus on palliative care development and implementation, building on the infrastructure we have identified, if the growing levels of health-related suffering at the end of life are to be addressed," he concluded.

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Provided by University of Glasgow 

The holidays remind us that grief cannot be wished away

by Heather Servaty-Seib, The Conversation

Experiencing grief during the holidays can be an isolating and difficult experience. Credit: Tommaso79/Shutterstock.com

The year-end holidays are a time of social gatherings, traditions and celebrations. They can also be a time of revisiting and reflection.

20 dec 2019--According to the Centers for Disease Control and Prevention, 2.8 million people die each year in the U.S. If we conservatively estimate four or five grievers per death, there are 11 to 14 million people who are experiencing their first holiday season without the presence of an important person who has died.

No matter how long it has been since a family member or friend has died, the holiday season can understandably bring grief to the forefront of our minds. Lost loved ones are no longer physically present, and our rituals can remind us of their absence in poignant ways. And it can be challenging for others to know how best to comfort and offer support.

As a licensed psychologist and professor of counseling psychology, my clinical and research interests for the past 25 years have focused on death, dying, grief and loss. A primary goal of my work has been to "make death talkable."

How do you speak of death at a time like this?

But how, you might ask, can death be talkable during the holidays? The general tendency within U.S. society is to avoid the topic. In the process, Americans tend to avoid not only our own grief, but also the grief of others.

My sense is that a good bit of this avoidance is connected to misunderstandings about the grieving process and problems with what society views as necessary, critical and "normal" for grief expression.

Psychiatrist Elisabeth Kübler-Ross's work with dying people, beginning in the mid-60s, was groundbreaking and facilitated increased conversations about death among health professionals, dying patients and their family members.

And yet the five stages that she observed in dying patients—denial, anger, bargaining, depression and acceptance—have taken on a life of their own. They have been applied well beyond the dying process, and have become a kind of prescription for grief—an unfolding that Kübler-Ross specifically warned against in her 1969 book.

When people focus on grief as a linear process with distinct stages and a clear endpoint, they are seeking to control and contain an aspect of life that is overwhelming, unpredictable and confusing. Although quite understandable, the attempt to put grief in a nice neat box has its costs. Most specifically, grieving individuals can begin to judge their own experiences, which can lead to just as much, if not more, pain than the grief itself.

A distinct experience

There are a few key points about grief that can make a tremendous difference for people during the holidays and beyond.

First, grief does not end. It is a reflection of attachment and love, and our connection with loved ones does not end when they die. Therefore, our grief will not and does not end. Grief is not a sickness to recover from, but rather an unfolding to experience.

Second, grief is not equal to sadness. In fact, it is not the same as emotions. Grief is multi-dimensional, and often incorporates emotional, cognitive, physiological, social and spiritual reactions. There is no indication in the literature that grievers must cry. Some grievers may be more emotional and social in their grief expression, while others may be more cognitive and physical.

Last, grief is unique to each person within their distinct familial, community and cultural contexts. Individuals will grieve based on who they are as people and based on the unique relationship they had with the person who died.

Those relationships can be quite dynamic and complex, and grief will reflect that complexity. It can often be challenging for family members and friends when they are grieving differently from one another. However, they are grieving different relationships with the loved one who died and their grief will then also be distinct.

Ways to bring comfort, if not actually joy

Contemporary theories expand far beyond stages to acknowledge the tasks of grief and the central nature of sense-making in the grieving process. For example: How do I integrate this death into my life story? Grief is not just about missing the person who died, but also about learning to live in a world where they are no longer physically present.

Developing a more nuanced understanding of the variability, adaptability, and unfolding nature of grief has encouraging implications for grievers and for those who seek to support them.

For grievers:

• Resist societal messages that limit, compartmentalize and minimize your grief.
• Observe your thoughts, feelings and actions, and honor the unique ways that you are expressing your grief.
• Remember that rituals related to grief go beyond formal services, and that post-funeral rituals can take many forms. Allow for recognition of both separation and connection. Annual rituals, such as those that may be incorporated into the holidays, can become new traditions and opportunities for meaningful reflection.

For those who seek to offer support:

• Acknowledge that grief does not end. Even brief messages of recognition and remembrance of their loss, regardless of the time since death, can be quite meaningful at the holidays and during other significant times.
• Keep in mind your level of closeness. If you know the griever well, then you will have more sense of what they will view as helpful. Consider offering tangible assistance in terms of errands, tasks, or responsibilities that you know will be difficult for them. If you do not know them well, keep your responses more inline with that level of relationship, such as sending emails and cards, or donating to a cause.
• Reflect on your own death anxiety and apprehension. Own it and then use it. Push through the common tendency to avoid those who are grieving and act on your thoughts of concern for them.

Remember that there is no set of words or phrases that will "fix" grief. It just does not work that way. What will make the difference is your presence and your willingness to reach out.

If it would help to consider specific statements, phrases that communicate presence and care, such as "I am here for you," or "I care about what happens to you," are more likely to be viewed as helpful than those focused on advice and forced cheerfulness, such as "You should keep busy," or "Do not take it so hard."

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Provided by The Conversation 

Are herpes virus infections linked to Alzheimer's disease?

by Baylor College of Medicine

PET scan of a human brain with Alzheimer's disease. Credit: public domain

Researchers at Baylor College of Medicine report today in the journal Neuron evidence that refutes the link between increased levels of herpes virus and Alzheimer's disease. In addition, the researchers provide a new statistical and computational framework for the analysis of large-scale sequencing data.

20 dec 2019--About 50 million people worldwide are affected by Alzheimer's disease, a type of progressive dementia that results in the loss of memory, cognitive abilities and verbal skills, and the numbers are growing rapidly. Currently available medications temporarily ease the symptoms or slow the rate of decline, which maximizes the time patients can live and function independently. However, there are no treatments to halt progression of Alzheimer's disease.

"Like all types of dementia, Alzheimer's disease is characterized by massive death of brain cells, the neurons. Identifying the reason why neurons begin and continue to die in the brains of Alzheimer's disease patients is an active area of research," said corresponding author Dr. Zhandong Liu, associate professor of pediatrics at Baylor and the Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital.

One theory that has gained traction in the past year is that certain microbial infections, such as those caused by viruses, can trigger Alzheimer's disease. A 2018 study reported increased levels of human herpesvirus 6A (HHV-6A) and human herpesvirus 7 (HHV-7) in the postmortem brain tissues of more than 1,000 patients with Alzheimer's disease when compared to the brain tissues of healthy-aging subjects or those suffering from a different neurodegenerative condition.

Presence of elevated levels of genetic material of herpes viruses indicated active infections, which were linked to Alzheimer's disease. In less than a year, this study generated a flurry of excitement and led to the initiation of several studies to better understand the link between viral infections and Alzheimer's disease.

Surprisingly, when co-author Dr. Hyun-Hwan Jeong, a postdoctoral fellow in Dr. Liu's group and others, reanalyzed the data sets from the 2018 study using the identical statistical methods with rigorous filtering, as well as four commonly used statistical tools, they were unable to produce the same results.

The team was motivated to reanalyze the data from the previous study because they observed that while the p-values (a statistical parameter that predicts the probability of obtaining the observed results of a test, assuming that other conditions are correct) were highly significant, they were being ascribed to data in which the differences were not visually appreciable.

Moreover, the p-values did not fit with simple logistic regression—a statistical analysis that predicts the outcome of the data as one of two defined states. In fact, after several types of rigorous statistical tests, they found no link between the abundance of herpes viral DNA or RNA and likelihood of Alzheimer's disease in this cohort.

"As high-throughput 'omics' technologies, which include those for genomics, proteomics, metabolomics and others, become affordable and easily available, there is a rising trend toward 'big data' in basic biomedical research. In these situations, given the massive amounts of data that have to be mined and extracted in a short time, researchers may be tempted to rely solely on p-values to interpret results and arrive at conclusions," Liu said.

"Our study highlights one of the potential pitfalls of over-reliance on p-values. While p-values are a very valuable statistical parameter, they cannot be used as a stand-alone measure of statistical correlation—data sets from high-throughput procedures still need to be carefully plotted to visualize the spread of the data," Jeong said. "Data sets also have to be used in conjunction with accurately calculated p-values to make gene-disease associations that are statistically correct and biologically meaningful."

"Our goal in pursuing and publishing this study was to generate tools and guidelines for big data analysis, so the scientific community can identify treatment strategies that will likely benefit patients," Liu said.

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More information: Hyun-Hwan Jeong et al, Are HHV-6A and HHV-7 Really More Abundant in Alzheimer's Disease?, Neuron (2019). DOI: 10.1016/j.neuron.2019.11.009

Journal information: Neuron 

Provided by Baylor College of Medicine 

Caring for transgender persons: What clinicians should know

by The Mount Sinai Hospital

Credit: CC0 Public Domain

One of the biggest barriers to care for transgender individuals is a lack of knowledgeable providers. In a move that reflects a growing recognition of transgender care needs within established medicine in the United States, The New England Journal of Medicine (NEJM) published a new review on the topic authored by experts from the Mount Sinai Health System.

20 dec 2019--The new review, titled "Care of Transgender Persons," appears in the December 19 issue of NEJM. Itaims to serve as a fundamental resource to help the medical community separate what is known from what is not in transgender health care.

In the United States, studies estimate that approximately 150,000 youths and 1.4 million adults identify as transgender. As sociocultural acceptance patterns evolve, clinicians will likely care for an increasing number of transgender people.

"The intention of the review is to provide straightforward guidance to address the gap that transgender individuals may face in their care," said the lead author of the review, Joshua Safer, MD, Executive Director of the Mount Sinai Center for Transgender Medicine and Surgery, and Professor of Medicine (Endocrinology, Diabetes, and Bone Disease) at the Icahn School of Medicine at Mount Sinai.

The feature begins with a case vignette that highlights a common clinical problem. Evidence supporting various strategies is then presented, followed by a review of formal guidelines, when they exist. Dr. Safer and his colleague, Vin Tangpricha, MD, Ph.D., Professor of Medicine at Emory University in Atlanta, then provide clinical recommendations.

Recommendations from the review include:

• Determining readiness for treatment for those who seek it by establishing that the patient has persistent gender incongruence and is competent to make medical decisions.
• Prescribing and managing hormone therapy based on expected impact and awareness of the potential adverse effects of the treatment.
• Screening by the clinician or mental health consultant for mental health conditions that may confound the assessment of gender identity or complicate management of care.
• Understanding the various surgical options for transgender individuals with consideration of the challenges associated with each.

"The most influential vehicle to effect long-lasting, meaningful change across current and future generations of clinicians in all specialties caring for transgender individuals is education," added Dr. Safer.

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More information: Joshua D. Safer et al. Care of Transgender Persons, New England Journal of Medicine (2019). DOI: 10.1056/NEJMcp1903650

Journal information: New England Journal of Medicine 

Provided by The Mount Sinai Hospital 

Tailored light improves quality of life for older adults with Alzheimer's disease

by Rebekah Mullaney, Rensselaer Polytechnic Institute

Credit: CC0 Public Domain

Most people associate Alzheimer's disease with profound memory loss, but it is often the symptoms—sleep disturbances, depression, and agitation—that are a challenge to treat, and can significantly reduce the quality of life for both the affected individual and their family members and caregivers.

20 dec 2019--In a research project funded by the National Institute on Aging (NIA), Mariana Figueiro, a professor and the director of the Lighting Research Center (LRC) at Rensselaer Polytechnic Institute, is investigating whether a tailored lighting intervention can lessen the impact of these symptoms in older adults living with Alzheimer's disease and related dementias (ADRD). She recently published her latest findings in the Journal of Clinical Sleep Medicine.

Using a variety of light sources, such as floor luminaires, light boxes, and light tables, to deliver the tailored, individualized lighting intervention, this 14-week randomized, placebo-controlled, crossover design clinical trial administered an all-day active (high circadian stimulus [CS] of 0.4) or control (low CS of < 0.1) lighting intervention to 46 patients with moderate to late-stage ADRD in eight long-term care facilities. The study employed wrist-worn actigraphy and standardized measures of sleep quality, mood, and behavior.

The study's primary aims were to extend earlier studies and to again validate the CS metric in the field by investigating the impact of the intervention on subjective and objective measures of nighttime sleep. The secondary aim was to determine whether the lighting intervention would improve caregiver-assessed participant scores in measures of depression, agitation, and quality of life. The CS metric is a measure of how effective a light exposure is for stimulating the human circadian system. Developed by the LRC from several lines of biophysical research, including those from basic retinal neurophysiology, the CS metric has been applied successfully in numerous field applications to improve sleep at night and reduce sleepiness during the day.

Results revealed that, compared to baseline, the active lighting intervention significantly improved sleep quality, and reduced depressive symptoms and agitation behavior.

The 24-hour light and dark pattern strongly determines a person's sleep-wake cycle, telling the body when to go to sleep and when to wake up. Studies have demonstrated that daytime light exposure of CS > 0.3 (approx. 350–500 lux at the eyes) can improve nighttime sleep efficiency and increase daytime wakefulness by promoting circadian entrainment.

Lighting in long-term care facilities is usually not bright enough during the day and perhaps too bright during the evening. Typical indoor lighting provides less than 100 lux at the eye, whereas being outside on a sunny day will provide anywhere from 1,000 to more than 10,000 lux at the eye. Older adults in long-term care facilities often spend their days and nights in dimly-lit rooms with minimal time spent outdoors, and thus, are not experiencing the robust daily patterns of light and dark that synchronize the body's circadian clock to local sunrise and sunset.

Therefore, it is understandable that many older adults in long-term care facilities are plagued by insomnia and other sleep disorders—yet, sleep could not be more important to their overall health and wellbeing. Recent research has shown that poor sleep may directly impact the onset and progression of Alzheimer's disease, and conversely, healthy, regular sleep patterns may prevent or slow progression of the disease. This research suggests a bidirectional relationship between sleep disruption and the deposit of amyloid beta, the main component of the amyloid plaques found in the brains of individuals diagnosed with Alzheimer's disease.

Older adults with ADRD experience severe dysfunctions of their sleep-wake cycle that clinically present as sundowning, excessive daytime sleepiness, nocturnal wandering, agitation, irritability, day-night reversal, and decreased cognitive functioning. Sleep problems are exacerbated in those with ADRD, whose circadian rhythms can become less consolidated, as manifested in increased nocturnal wandering. This population is also at higher risk for depression and agitation behavior. These disturbances can lead to their placement in long-term care facilities, where they experience even greater inactivity and reduced exposure to daytime circadian-effective light, exacerbating their symptoms further.

Figueiro began work on her first major research grant from the NIA in 2010, measuring circadian light exposures in individuals with ADRD. Her research revealed that individuals with ADRD were exposed to lower light levels, exhibited lower activity levels, and experienced greater circadian disruption than healthy older adults. She then focused on a specific challenge: delivering light in a way that was highly effective for individuals with ADRD. A successful example of this tailored, personalized lighting intervention is the light table, which can deliver a strong dose of light at the eyes, an important factor in stimulating the circadian system. Light has to enter the eye to be effective for circadian entrainment.

Although a Cochrane review published in 2014 casts doubt on the efficacy of light therapy for improving sleep and behavior in ADRD patients, if carefully specified and implemented, tailored lighting designed to maximally impact the circadian system can be a powerful nonpharmacological intervention for improving sleep, mood, and behavior in persons living with ADRD, as shown in this study and in previous studies.

"When delivered appropriately, using CS and different delivery modes, and accurately measured, using calibrated personal light meter devices, a lighting intervention tailored to maximally entrain the circadian system will significantly improve sleep quality, depressive symptoms, and agitation behavior in patients with ADRD," Figueiro said. "It is important to use, deliver and measure the right lighting to see the positive effects."

"We are hopeful that designers of senior facilities will now have the confidence to specify lighting solutions that provide a minimum CS of 0.3 during the day to this often neglected population," said Mark Rea, who was one of the authors of the study.

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More information: Mariana G. Figueiro et al. Effects of a Tailored Lighting Intervention on Sleep Quality, Rest–Activity, Mood, and Behavior in Older Adults With Alzheimer Disease and Related Dementias: A Randomized Clinical Trial, Journal of Clinical Sleep Medicine (2019). DOI: 10.5664/jcsm.8078

Journal information: Journal of Clinical Sleep Medicine