Pneumonia or sepsis in adults associated with increased risk of cardiovascular disease

Pneumonia or sepsis in adults that results in hospital admission is associated with a six-fold increased risk of cardiovascular disease in the first year, according to research published today in the European Journal of Preventive Cardiology. Cardiovascular risk was more than doubled in years two and three after the infection and persisted for at least five years.

10 aug 2017--"Severe infections in adulthood are associated with a contemporaneously raised risk of cardiovascular disease," said last author Professor Scott Montgomery, director of the clinical epidemiology group, Örebro University, Sweden. "Whether this raised risk persists for several years after infection is less well established."
This study examined if hospital admission for sepsis or pneumonia is associated with an increased risk of cardiovascular disease in the years following infection, and whether there is a period of particularly heightened risk.
The study included 236 739 men born between 1952 and 1956 who underwent extensive physical and psychological examinations at around age 18 years as part of compulsory military conscription assessments. The researchers obtained infection and cardiovascular disease diagnoses from a register that has recorded information on patients admitted to hospital since 1964. The men were followed from late adolescence into middle age (follow-up was completed in 2010).
The researchers analysed the associations between a first infection with sepsis or pneumonia that resulted in hospital admission with subsequent cardiovascular disease risk at pre-specified time intervals post-infection (0-1, >1-2, >2-3, >3-4, >4-5, and 5+ years after hospital admission for the infection).
During the follow-up period, a total of 46 754 men (19.7%) had a first diagnosis of cardiovascular disease. There were 9 987 hospital admissions for pneumonia or sepsis among 8 534 men who received these diagnoses.
The researchers found that infection was associated with a 6.33-fold raised risk of cardiovascular disease during the first year after the infection. In the second and third years following an infection, cardiovascular disease risk remained raised by 2.47 and 2.12 times. Risk decreased with time but was still raised for at least five years after the infection by nearly two-fold (hazard ratio 1.87).
Similar findings were observed for coronary heart disease, stroke, and fatal cardiovascular disease. The persistently raised risk could not be explained by subsequent severe infections.
"Our results indicate that the risk of cardiovascular disease, including coronary heart disease and stroke, was increased after hospital admission for sepsis or pneumonia," said lead author Dr Cecilia Bergh, an affiliated researcher at Örebro University. "The risk remained notably raised for three years after infection and was still nearly two-fold after five years."
When the researchers examined the relationship between other risk factors such as high blood pressure, overweight, obesity, poorer physical fitness, and household crowding in childhood, they found that infection was associated with the highest magnitude of cardiovascular disease risk in the first three years post-infection.
Professor Montgomery said: "Conventional cardiovascular risk factors are still important but infection may be the primary source of risk for a limited time."
The authors said the results point to a causal relationship, since cardiovascular disease risk is very high immediately after infection and reduces with time. Persistent systemic inflammation after a severe infection may play a role, as inflammation is a risk for cardiovascular disease. Most patients with sepsis or pneumonia recover but many still have high circulating inflammatory markers after the acute phase of the infection.
Professor Montgomery said: "Our findings provide another reason to protect against infection and suggest that there is a post-infection window of increased cardiovascular disease risk. We did not study any interventions that could be initiated during this period, but preventative therapies such as statins could be investigated."

More information: Bergh C, et al. Severe infections and subsequent delayed cardiovascular disease. European Journal of Preventive Cardiology. 2017. DOI: 10.1177/2047487317724009


Provided by European Society of Cardiology

Antibiotic therapy for nearly 1 in 4 adults with pneumonia does not work

Antibiotic treatment ineffective for one in four adults with pneumonia. Credit: ATS

Approximately one in four (22.1 percent) adults prescribed an antibiotic in an outpatient setting (such as a doctor's office) for community-acquired pneumonia does not respond to treatment, according to a new study presented at the 2017 American Thoracic Society International Conference.

24 may 2017--"Pneumonia is the leading cause of death from infectious disease in the United States, so it is concerning that we found nearly one in four patients with community-acquired pneumonia required additional antibiotic therapy, subsequent hospitalization or emergency room evaluation," said lead author James A. McKinnell, MD, an LA BioMed (Los Angeles, CA) lead researcher and infectious disease specialist. "The additional antibiotic therapy noted in the study increases the risk of antibiotic resistance and complications like C. difficile ("C diff") infection, which is difficult to treat and may be life-threatening, especially for older adults."
Dr. McKinnell and colleagues conducted this study because current community-acquired pneumonia guidelines from the American Thoracic Society and the Infectious Disease Society of America, published in 2007, provide some direction, but large-scale, real-world data are needed to better understand and optimize antibiotic choices and to better define clinical risk factors that may be associated with treatment failure.
The researchers examined databases containing records for 251,947 adult patients who were treated between 2011 and 2015 with a single class of antibiotics (beta-lactam, macrolide, tetracycline, or fluoroquinolone) following a visit to their physician for treatment for community-acquired pneumonia. The scientists defined treatment failure as either the need to refill antibiotic prescriptions, antibiotic switch, ER visit or hospitalization within 30 days of receipt of the initial antibiotic prescription. The total antibiotic failure rate was 22.1 percent, while patients with certain characteristics—such as older age, or having certain other diseases in addition to pneumonia—had higher rates of drug failure. After adjusting for patient characteristics, the failure rates by class of antibiotic were: beta-lactams (25.7 percent), macrolides (22.9 percent), tetracyclines (22.5 percent), and fluoroquinolones (20.8 percent).
"Our findings suggest that the community-acquired pneumonia treatment guidelines should be updated with more robust data on risk factors for clinical failure," said Dr. McKinnell. "Our data provide numerous insights into characteristics of patients who are at higher risk of complications and clinical failure. Perhaps the most striking example is the association between age and hospitalization: Patients over the age of 65 were nearly twice as likely to be hospitalized compared to younger patients when our analysis was risk adjusted and nearly three times more likely in unadjusted analysis. Elderly patients are more vulnerable and should be treated more carefully, potentially with more aggressive antibiotic therapy."
Dr. McKinnell also stated that his study found substantial regional variations in treatment outcomes, which are not addressed in a specific way in the community-acquired pneumonia guidelines. In addition, the study showed that thousands of patients who suffer from other conditions - such as chronic obstructive pulmonary disease, cancer or diabetes - were not treated with combination antibiotic therapy or respiratory fluoroquinolone, as the guidelines recommend.
"While certain aspects of the guidelines need to be updated, some prescribers also have room for improvement and should implement the current guidelines," he concluded.

More information: Abstract 8450: Clinical Predictors of Antibiotic Failure in Adult Outpatients with Community-Acquired Pneumonia


Provided by American Thoracic Society

What do you know about pneumonia?

Pneumonia is an infection that inflames the air sacs in one or both lungs. The air sacs may fill with fluid or pus (purulent material), causing cough with phlegm or pus, fever, chills and difficulty breathing. A variety of organisms, including bacteria, viruses and fungi, can cause pneumonia.

CAUSES

17 sept 2016--Many germs can cause pneumonia. The most common are bacteria and viruses in the air you breathe. Your body usually prevents these germs from infecting your lungs. But, sometimes, these germs can overpower your immune system - even if your health is generally good.
Pneumonia is classified according to the types of germs that cause it and where you got the infection.

COMMUNITY-ACQUIRED PNEUMONIA

Community-acquired pneumonia is the most common type of pneumonia. It occurs outside of hospitals or other health care facilities. It may be caused by:
- Bacteria. The most common cause of bacterial pneumonia in the U.S. is Streptococcus pneumoniae. This type of pneumonia can occur on its own or after you've had a cold or the flu. It may affect one part (lobe) of the lung, a condition called lobar pneumonia.
- Bacteria-like organisms. Mycoplasma pneumoniae also can cause pneumonia. It typically produces milder symptoms than do other types of pneumonia. Walking pneumonia is an informal name given to this type of pneumonia, which typically isn't severe enough to require bed rest.
- Fungi. This type of pneumonia is most common in people with chronic health problems or weakened immune systems, and in people who have inhaled large doses of the organisms. The fungi that cause it can be found in soil or bird droppings, and vary depending on geographic location.
- Viruses. Some of the viruses that cause colds and the flu can cause pneumonia. Viruses are the most common cause of pneumonia in children younger than 5. Viral pneumonia is usually mild. But, in some cases, it can become serious.

TREATMENT

Treatment for pneumonia involves curing the infection and preventing complications. People who have community-acquired pneumonia usually can be treated at home with medication. Although most symptoms ease in a few days or weeks, the feeling of tiredness can persist for a month or more.
Specific treatments depend on the type and severity of your pneumonia, your age and your overall health. The options include:
- Antibiotics. These medicines are used to treat bacterial pneumonia. It may take time to identify the type of bacteria causing your pneumonia and choose the best antibiotic to treat it. If your symptoms don't improve, your doctor may recommend a different antibiotic.
- Cough medicine. This medicine may be used to calm your cough so that you can rest. Because coughing helps loosen and move fluid from your lungs, it's a good idea not to eliminate your cough completely. In addition, you should know that few studies have looked at whether over-the-counter cough medicines lessen coughing caused by pneumonia. If you want to try a cough suppressant, use the lowest dose that helps you rest.
- Fever reducers/pain relievers. You can take fever reducers/pain relievers as needed, such as aspirin, ibuprofen (Advil, Motrin IB and others) and acetaminophen (Tylenol and others).

Community acquired pneumonia increases long-term morbidity and mortality

Having had community-acquired pneumonia (CAP) greatly increases the risk of long-term morbidity and mortality compared to the general population who have never had CAP, according to a new study from researchers in Canada, the longest and largest outcomes study of patients with CAP reported to date.

19 jun 2015--"Although the short-term adverse health consequences of CAP are well known, the long-term effects of the disease are less clear," said Dean T. Eurich, PhD, MSc, BSP, of the University of Alberta in Edmonton, Alberta, Canada. "In our large population-based study of more than 6,000 adults with CAP and almost 30,000 matched controls, we found that CAP patients have high rates of long-term morbidity and mortality compared to those who have never had CAP, irrespective of their age."

The study was published online ahead of print publication in the American Thoracic Society's American Journal of Respiratory and Critical Care Medicine.

During a median of 9.8 years of follow-up, 2,858 CAP patients died, an absolute risk difference of 30 excess deaths per 1000 patient years of follow-up and a greater that 50% relative increased rate of mortality among CAP patients. Although CAP patients under 25 years of age had the lowest absolute risk difference for mortality, and those over 80 years had the highest absolute risk difference, young CAP adults in fact had the worst relative outcomes of all patients with over a 2-fold increased rate of mortality relative to controls.

The mortality rate was significantly elevated among CAP patients even after including the 406patients who died within 30 days of the index event and excluding an additional 248 patients who died within 90 days of admission.

In addition to this increased mortality risk, the absolute rates of all-cause hospitalization, emergency department visits, and CAP-related hospital visits, were all significantly higher in CAP patients compared to controls. "Indeed CAP is still considered 'the old man's friend' because of the almost assured high mortality; however our results lend strong support to the alternate proposition that CAP ought to also be considered the young adult's adversary," said Dr. Eurich.

"Future research may help explain the factors underling these increased long-term risks in CAP patients and inform a treatment approach in these patients," said Dr. Eurich."Some of these adverse events may be preventable and our results suggest that we have likely underestimated the cost effectiveness, the impact and importance of immunizations that prevent pneumonia."

More information: The study is available at www.atsjournals.org/doi/abs/10… -0140OC#.VXmxsPlVhHw

Provided by American Thoracic Society

Hospitalized for pneumonia? Your risk of cardiovascular disease is higher

Your chance of having a heart attack or stroke increases significantly if you have been hospitalized for pneumonia, according to a paper published today in the influential JAMA (Journal of the American Medical Association).

21 jan 2015--"The main conclusion from our study is that someone hospitalized for pneumonia should be considered at greater risk of developing cardiovascular disease," said lead author Dr. Vicente Corrales-Medina, an infectious diseases physician and researcher at The Ottawa Hospital, and assistant professor with the University of Ottawa's Faculty of Medicine.

"This means two things. First, it provides yet another reason to do everything we can to prevent pneumonia from occurring in the community, through vaccination and basic hand hygiene, for example," he continued. "This is especially important for the elderly and those with other risk factors for cardiovascular disease, such as diabetes, smoking and high cholesterol."

"Second, once pneumonia has occurred, physicians should develop a care plan understanding that these patients are more likely to develop cardiovascular disease in the weeks, months and years following their recovery from this infection," added Dr. Corrales-Medina. "Such measures could include screening and primary prevention strategies for cardiovascular disease."

While other studies have made the connection between pneumonia hospitalization and cardiovascular disease, this is the first to only look at pneumonia patients with no previous history of cardiovascular disease while also taking into account the effect of other established cardiovascular risk factors. By doing so, their results strongly indicate that hospitalization for pneumonia should be considered its own risk factor for future cardiovascular disease.

The JAMA paper used records of 3,813 people from two community health studies, both based in the United States. One enrolled participants aged 65 and older and the other enrolled participants aged 45 to 64. The JAMA study analysed health data of 1,271 pneumonia patients against 2,542 control patients (matched by age) over a period of 10 years.

Results showed that these pneumonia patients had a raised level of risk for cardiovascular disease over the entire 10 years, with the highest risk experienced in the first year. For example, in the group aged 65 and older, a pneumonia patient was four times more likely to develop cardiovascular disease in the first 30 days following the infection. In the tenth year, they were a little less than twice as likely to develop cardiovascular disease.

Another way of looking at it: The 10-year risk of developing cardiovascular disease for a 72-year-old woman with two cardiovascular risk factors (hypertension and smoking) increases from 31% to 90% if she is hospitalized for pneumonia.

Results from the group aged 45 to 64 showed that the risk was higher in the first two years, but not significantly raised after that. In this younger group, a pneumonia patient was 2.4 times more likely to develop cardiovascular disease in the first 90 days after the infection.

Dr. Corrales-Medina's current research is focused on trying to determine what biological mechanisms are responsible for this raised risk of cardiovascular disease after pneumonia, in order to develop therapies to prevent the subsequent onset of cardiovascular disease.

More information: "Association Between Hospitalization for Pneumonia and Subsequent Risk of Cardiovascular Disease" JAMA, 2015. doi:10.1001/jama.2014.18229

Provided by Ottawa Hospital Research Institute

How pneumonia bacteria can compromise heart health

Microlesions (indicated by circles) in the heart of a mouse 30 hours after induction of invasive pneumococcal disease. Credit: PLoS Pathogens, 2014

Bacterial pneumonia in adults carries an elevated risk for adverse cardiac events (such as heart failure, arrhythmias, and heart attacks) that contribute substantially to mortality—but how the heart is compromised has been unclear. A study published on September 18th in PLOS Pathogens now demonstrates that Streptococcus pneumoniae, the bacterium responsible for most cases of bacterial pneumonia, can invade the heart and cause the death of heart muscle cells.

19 sept 2014--Carlos Orihuela, from the University of Texas Health Science Center in San Antonio, USA, and colleagues initially studied the reasons for heart failure during invasive pneumococcal disease (when S. pneumoniae bacteria infect major organs such as the lungs, bloodstream, and brain) in mice, and subsequently confirmed some of their main findings in rhesus macaques and in heart tissue from deceased human patients.

Mice with severe invasive pneumococcal disease showed elevated levels of troponin, a marker for heart injury, in their blood. They also had abnormal EKGs. When the researchers examined the hearts of the mice, they found microscopic sites of injury (called microlesions) in the heart muscle. S. pneumoniae were found within these microlesions, indicating the bacteria were able to invade and multiply within the heart. Looking in more detail, the researchers identified dying heart muscle cellsin the tissue surrounding microlesions.

At the molecular level, the researchers found that the S. pneumoniae toxin pneumolysin was present within the microlesions and responsible for heart muscle cell death. They also showed that S. pneumoniae requires a molecule called CbpA to exit the bloodstream and invade the heart. Moreover, an experimental vaccine formulation composed of CbpA and a non-toxic version of pneumolysin generated antibodies that protected mice against cardiac invasion and heart damage.

Having obtained tissues from three rhesus macaques that had died from pneumococcal pneumonia, the researchers found cardiac microlesions that were similar in size and appearance to those seen in mice, but without the presence of S. pneumoniae bacteria. The situation was similar in cardiac samples from human patients who had died from invasive pneumococcal disease. Two of the samples (they looked at a total of nine) showed microlesions, but the lesions did not contain bacteria.

As the macaques and the human patients had been treated with antibiotics, the researchers wondered whether the bacteria had caused the lesions but subsequently been killed by the treatment. To test this, they infected mice with S. pneumoniae and treated them with a high-dose antibiotic (ampicillin) when the lesions were first apparent. The hearts of these mice looked similar to the macaques and human samples, with clear presence of microlesions but devoid of bacteria. As the researchers discuss, ampicillin acts by breaking bacteria apart and releasing their contents, including pneumolysin, and this could exacerbate the death of heart muscle cells. Alternative antibiotics that do not spill their bacterial targets' contents exist and might be advantageous.

Having shown for the first time that S. pneumoniae can directly damage the heart—which could help explain the link between pneumonia and adverse heart events—the researchers conclude that "research is merited to determine the true frequency of cardiac microlesions in patients hospitalized with invasive pneumococcal disease, if modifications in antibiotic therapy improve long-term outcomes, and if prevention of cardiac damage is an indication for vaccination."

More information: Streptococcus pneumoniae Translocates into the Myocardium and Forms Unique Microlesions That Disrupt Cardiac Function. PLoS Pathogens, 2014; 10 (9): e1004383 DOI: 10.1371/journal.ppat.1004383

Provided by Public Library of Science

Study examines postoperative pneumonia prevention program in surgical ward

A postoperative pneumonia prevention program for patients in the surgical ward at a California Veterans Affairs hospital lowered the case rate for the condition, which can cause significant complications and increase the cost of care.

24 july 2014--Pneumonia is a common infection that accounts for about 15 percent of all hospital-acquired infections and as much as 3.4 percent of complications among surgical patients.

The study outlines the results (2008-2012) for a postoperative pneumonia prevention program for patients who were not on a mechanical ventilator in the hospital's surgical ward. The prevention program had several components, including ongoing education for surgical ward nursing staff on pneumonia prevention, coughing and deep-breathing exercises with incentive spirometer, twice daily oral hygiene with chlorhexidine, walking, sitting up to eat and elevated head-of-bed.

Between 2008 and 2012, there were 18 cases of postoperative pneumonia among 4,099 at-risk hospitalized patients for a case rate of 0.44 percent. That is a 43.6 percent decrease from the hospital's preintervention rate of 0.78 percent. Pneumonia rates in all years were lower than the preintervention rate (0.25 percent, 0.50 percent, 0.58 percent, 0.68 percent and 0.13 percent in 2008-2012, respectively).

"Despite the limitations listed earlier, our study supports the concept that successful and sustained reduction of pneumonia among postoperative patients requires multiple performance measures and unrelenting standardized quality improvement efforts."

More information: JAMA Surgery. Published online July 23, 2014. DOI: 10.1001/jamasurg.2014.1216

Provided by The JAMA Network Journals

Recurrent pneumonia not common, lung expert says

Pneumonia is one of the most common of lung infections among the elderly but concerns of underlying conditions arise when it recurs, a leading South African pulmonologist said Sunday.

10 jun 2013--Nelson Mandela was admitted Saturday in a "serious but stable" condition for a recurrent lung infection.

It is his fourth hospital stay since December and his third for lung infection. The Nobel peace prize laureate, who turns 95 next month, was in April hospitalised for 10 days for pneumonia treatment. Officials have not specified if the latest infection afflicting Mandela is pneumonia.

Of the different types of lung infections, "pneumonia is the most serious and the most common in elderly patients," said professor Guy Richards, director of critical care at Johannesburg's Charlotte Maxeke Academic Hospital.

But when it recurs, it means there would be other underlying conditions.

"It's very unusual to get the common pneumonia occurring recurrently unless there's a specific reason for it.

"And those sorts of things are that if your lung has been damaged previously, for example if you had tuberculosis, then often those damaged areas will be colonized with bacteria which are able to cause recurrent infections," he told AFP.

Acute pneumonia can damage other organs of the body such as the kidneys or affect blood pressure, he said.

"If you have severe pneumonia, your body mounts an immune response to that pneumonia. We then sometimes have an overwhelming immune response which can result in multiple organ disfunction," said Richards.

"So for example they might present not only with a chest infection but then they might develop kidney failure, or they might develop failure of the heamodynamic system, their blood pressure might go down."

Treatment, under normal circumstances last just days, but in serious cases where hospitalisation is required, it can last several weeks.

"The majority of patients with pneumonia don't need to be admitted but those that are admitted would generally remain for three to four days. If they develop multiple organ failure and they are in ICU (intensive care unit) and they are on a ventilator, then we are talking weeks."

While he disease can affect people of all ages, it common among the elderly.

"Pneumonia was in fact known for many years as an 'old man's friend'. In other words it was the final illness that often took him away," said Richards.

Studies: Pneumonia is misdiagnosed on patient readmissions

DETROIT23 oct 2010 – Patients were misdiagnosed with pneumonia at an alarming rate when they were readmitted to the hospital shortly after a previous hospitalization for the same illness, according to two Henry Ford Hospital companion studies.

Researchers say the misdiagnoses led to overuse of antibiotics and increased health care costs. Pneumonia ranks second to congestive heart failure as the reason for readmission within 30 days of a previous hospitalization.

Led by Henry Ford Infectious Diseases physicians Hiren Pokharna, M.D., and Norman Markowitz, M.D., researchers found that:

• 72 percent of patients were misdiagnosed with pneumonia upon readmission to the same hospital.
• African-Americans were twice more likely than Caucasians to be misdiagnosed with pneumonia.
• Patients who smoke or have lung disease were likely to be misdiagnosed with pneumonia.
• 72 percent of the misdiagnoses occurred in the Emergency Department.
• Fewer than 33 percent of patients had any outpatient follow-up care prior to their readmission.

Results of the two companion studies will be presented Friday at the 48th annual meeting of the Infectious Diseases Society of America Oct. 21-24 in Vancouver.

"These studies show that we need to increase awareness among physicians about using the diagnostic standards and criteria set forth in the Centers for Disease Control and Prevention's National Healthcare Safety Network for diagnosing pneumonia at the time of readmission," says Dr. Pokharna, a fellow at Henry Ford and the lead author of the companion studies.

"This also points to the importance of using X-ray for ruling out pneumonia. And once pneumonia is ruled out, the antibiotics can be discontinued."

In seeking to explain the difficulty of diagnosing pneumonia and high prevalence of misdiagnoses, Henry Ford researchers examined medical records of 127 patients diagnosed with pneumonia between December 2008 and December 2009 and readmitted within 30 days of a previous hospitalization.

Researchers found that 92 of the 127 patients were misdiagnosed with health care associated pneumonia using CDC/National Healthcare Safety Network criteria. Health care associated pneumonia is a newly recognized form of pneumonia in patients who had recent close contact with a health care system, either through a hospital, outpatient dialysis center, nursing home or long-term care facility. The classification was added with the shift from hospital-based care to home-based care.

Researchers cited several reasons for the misdiagnoses, including pre-existing lung disease and abnormalities on chest X-rays.

###

The studies were funded by Henry Ford Hospital.

Pollution linked to hospitalizations for pneumonia in older adults

Older adults with long-term exposure to higher levels of pollution are at higher risk for hospitalization for pneumonia, according to researchers in Canada.

26 dec 2009--"Our study found that among older individuals, long-term exposure to traffic pollution independently increased their risk of hospitalization for pneumonia," said principal investigator, Mark Loeb, M.D., of McMaster University.

The research will be published in the January 1 issue of the American Thoracic Society's American Journal of Respiratory and Critical Care Medicine.

Pneumonia is a leading cause of sickness and death among older adults, and rates of hospitalizations for pneumonia among patients 65 and older have been increasing in recent years.

In addition to traffic pollution associated with roads, Hamilton has a large industrial steel-making complex in the north end of the city, creating a large exposure zone for residents. The researchers recruited 365 older adults from Hamilton, Ontario, who had been hospitalized with radiologically confirmed pneumonia in one of Hamilton's four emergency departments between 2003 and 2005. Control subjects from the same catchment areas as the patients were enrolled contemporaneously, and then compared their exposures to nitrogen dioxide (NO2), sulfur dioxide (SO2), and fine particulate matter less that 2.5 μm (PM2.5) using data from air-quality monitoring stations and land use regression models.

The researchers found that long-term (more than 12 months) exposures to NO2 and PM2.5 were each associated with a more than doubled risk of hospitalization from pneumonia. Individuals with long-term exposure to NO2 had 2.3 times the risk for hospitalization with pneumonia; for PM2.5, the odds ratio was 2.26.

"We postulate that long-term exposure to air pollution may have increased individuals' susceptibility to pneumonia by interfering with innate immune defenses designed to protect the lung from pathogens; this may have included epithelial cell damage, reductions in bronchial macrophages, or reductions in natural killer cells," said Dr. Loeb.

Exposure to SO2 was not associated with increased risk of hospitalization.

"Given the large population exposure to ambient air pollution, the results of this study highlight the important health impact that long-term exposure to ambient air pollution can have on respiratory infections," wrote Dr. Loeb. "It also emphasizes the need to monitor emissions from vehicles, given that ground level NO2 is derived predominantly from traffic."

"While we don't know what is increasing the rates of pneumonia, we felt that studying air pollution was a good idea. Assessing if there is a correlation between rising pneumonia rates and increasing air pollution would be of interest," said Dr. Loeb.

In future research, Dr. Loeb hopes to examine whether there is a genetic component to susceptibility to the health effects of pollution. "Examining genetic variants to see if there is interaction between genetic basis and air pollution in the causal pathway of pneumonia would be very interesting," he said.

Fast, accurate urine test for pneumonia possible, study finds

10 dec 2009--Doctors may soon be able to quickly and accurately diagnose the cause of pneumonia-like symptoms by examining the chemicals found in a patient's urine, suggests a new study led by UC Davis biochemist Carolyn Slupsky.

Pneumonia is a lung infection that annually sickens millions of people in the United States, resulting in approximately 500,000 hospitalizations and thousands of deaths. A rapid, accurate diagnostic test for pneumonia could save lives by enabling doctors to begin appropriate treatment earlier.

Using technology known as nuclear magnetic resonance spectroscopy, the researchers were able to identify a chemical "fingerprint" for the type of pneumonia caused by the bacterium Streptococcus pneumoniae, and compare this to the chemical fingerprints for other types of pneumonia and noninfectious lung diseases.

Findings from the study, conducted by Slupsky and colleagues in Canada and Australia, are discussed in a research profile in the December issue of the Journal of Proteome Research. A patent is pending on the diagnostic procedure.

"This is the first study to demonstrate that NMR-based analysis of metabolites in urine has the potential to provide rapid diagnosis of the cause of pneumonia," said Slupsky, an assistant professor in UC Davis' departments of Nutrition, and Food Science and Technology. She is also a faculty member in UC Davis' Foods for Health Institute.

"It also shows that we can use this technology to quickly and easily monitor patient recovery," Slupsky said. "The goal is a tool for rapid, accurate diagnosis so that patients can quickly begin treatment with the appropriate medication."

Currently, pneumonia is diagnosed by a combination of clinical symptoms, X-rays and analysis of a patient's blood or sputum by bacterial culture. Such tests usually take more than 36 hours to complete and tend to yield a high rate of false-positive results. Previous studies have shown that more than 80 percent of patients admitted to the hospital with pneumonia are misdiagnosed, leading to delays in treatment with the appropriate antibiotic.

About pneumonia

Pneumonia is an infection of the lower respiratory tract that causes symptoms such as difficulty in breathing, fever, chest pains and cough. It can be caused by bacteria, viruses, fungi and parasites, and is difficult to diagnose because other noninfectious ailments can mimic pneumonia.

Streptococcus pneumonia is the major cause of community-acquired, rather than hospital-acquired, pneumonia. It can become life threatening in anyone, but is particularly worrisome in elderly patients, smokers and people with weakened immune systems or chronic lung diseases.

Metabolomics study

In the new study, Slupsky and colleagues applied "metabolomics" — the study of the chemicals produced by the body's metabolic processes — to develop a profile for pneumonia as it appears in a patient's urine.

To do this, they analyzed hundreds of urine samples collected from both healthy individuals and patients with a variety of pulmonary diseases or infections. In the process, they measured 61 metabolites in urine samples using NMR spectroscopy.

They found that urine from patients infected with pneumonia caused by Streptococcus pneumoniae had a telltale chemical profile that clearly distinguished those people from healthy individuals or patients with other ailments.

"By analyzing urine samples collected at various intervals during the patient's hospitalization, we could actually observe sick patients recover because their recovery was reflected in the chemical composition of their urine," Slupsky said.

She noted that the research team was surprised to find that most of the changes in metabolites related to infection by Streptococcus pneumoniae were caused by the body's response to the infection rather than by the invading bacteria.

"In future studies, we hope to explore how bacteria and other microbes interact with the body of the individual they infect, and how these interactions alter metabolism in the body, resulting in unique metabolite profiles in the urine," she said.

Slupsky conducted this research while at the University of Alberta. She joined UC Davis in July 2008. Her research focuses on interactions between the human body and bacteria, as they relate to health and disease conditions.

She collaborated on the study with researchers at the University of Alberta, University of Toronto and Austin Health in Australia.

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Funding for the study was provided by the Alberta Heritage Foundation for Medical Research, the Lung Association of Alberta and the Northwest Territories, Western Economic Development, and Alberta Advanced Education and Technology.

About UC Davis

For 100 years, UC Davis has engaged in teaching, research and public service that matters to California and transforms the world. Located close to the state capital, UC Davis has 31,000 students, an annual research budget that exceeds $500 million, a comprehensive health system and 13 specialized research centers. The university offers interdisciplinary graduate study and more than 100 undergraduate majors in four colleges — Agricultural and Environmental Sciences, Biological Sciences, Engineering, and Letters and Science — and advanced degrees from five professional schools — Education, Law, Management, Medicine and Veterinary Medicine.

Statins Don't Lower Risk Of Pneumonia In Elderly

22 june 2009--Taking popular cholesterol-lowering statin drugs, such as Lipitor® (atorvastatin), does not lower the risk of pneumonia. That's the new finding from a study of more than 3,000 Group Health patients published online on June 16 in advance of the British Medical Journal's June 20 print issue.

"Prior research based on automated claims data had raised some hope-and maybe some hype-for statins as a way to prevent and treat infections including pneumonia," said Sascha Dublin, MD, PhD, a physician at Group Health and assistant investigator at Group Health Center for Health Studies. "But when we used medical records to get more detailed information about patients, our findings didn't support that approach."

In fact, Dublin's population-based case-control study found that pneumonia risk was, if anything, slightly higher (26%) in people using a statin than in those not using any; and this extra risk was even higher (61%) for pneumonia severe enough to require being hospitalized.

"As a doctor, I'm a fan of statins for what they've been proven to do: lowering cholesterol and risk of heart disease and stroke in people who've had either disease or are at risk for them," said Dublin. Statins are HMG coenzyme A reductase inhibitors, which also include Zocor® (simvastatin) and Mevacor® (lovastatin). This class of medications lessens inflammation, which plays a role in infections.

"But now we and some others have found that statins may have gotten some unearned credit for health benefits that they don't actually have, including preventing pneumonia," Dublin said. Suggestions from prior research had led to calls for expensive randomized controlled trials of statins to prevent or treat infection. "But our study indicates that such trials would be an ill-advised use of limited research funds at this time," she added.

Why the discrepancy between this new study and earlier ones? "Healthy-user bias is one reason," said Dublin. In other words, compared to people who don't take statins, those who do may be healthier and have healthier habits that lower their risks of unrelated diseases such as pneumonia. And that's just what she found: Study patients who were on statins were less frail or disabled and also more likely to be vaccinated against flu or pneumococcal pneumonia. They were less likely to smoke, to have dementia, or to need help with bathing or walking.

Unlike the previous research on statins and pneumonia, Dublin's study made great efforts to control for this bias, including reviewing medical records in detail for every study subject. It confirmed that every pneumonia event was a true case of pneumonia, which prior studies rarely did. And it focused on relatively healthy elderly people. All had intact immune systems and none lived in a nursing home. She studied the same 65- to 94-year-old patients, with their records coded to protect their privacy, as in earlier Group Health research, published in The Lancet in 2008. That work showed the flu vaccine didn't protect the elderly from pneumonia as much as had been thought.

"We did an old-fashioned 'chart review,'" said Dublin. "By reading the text in the medical records, you catch crucial details."

Older men more likely than women to die after pneumonia

Biological response to infection differs between sexes

PITTSBURGH,30 april 2009 – Differing biological response to infection between men and women may explain higher death rates among older men who are hospitalized with community-acquired pneumonia (CAP). The findings, published online in the Critical Care Medicine journal, may have important implications for understanding sex differences in life expectancy.

"Our study found that men with CAP were less likely to survive after an infection compared to women and this was not explained by differences in demographics, health behavior, chronic health conditions or quality of care," said Sachin Yende, M.D., assistant professor in the Department of Critical Care Medicine at the University of Pittsburgh School of Medicine and corresponding author of the study.

The researchers measured blood levels of inflammatory indicators, including tumor necrosis factor (TNF) and interleukins 6 and 10, coagulation indicators including Factor IX, and fibrinolysis indicators including D-dimer concentrations. They found patterns in these biomarkers that suggest men generate a stronger inflammatory and coagulation response and, perhaps, break up blood clots more quickly than women in response to infection. "These differences in inflammatory, coagulation and fibrinolysis biomarkers among men may explain the reduced short-term and long-term survival," said Dr. Yende.

Data were gathered from the multicenter Genetic and Inflammatory Markers of Sepsis (GenIMS) study. Participants were enrolled upon emergency department admission at 28 academic and community hospitals in Pennsylvania, Connecticut, Michigan and Tennessee from 2001 to 2003. The study included 2,320 subjects, with a mean age of 64.9 years, 1,136 of whom were men. The men were sicker on admission, more likely to be smokers, and had at least one chronic health condition, such as cardiac disease or cancer. Severe sepsis occurred in 588 (31 percent) subjects. Of these, about half had severe sepsis on their first day of hospitalization.

Men had a higher risk than women of death at 30 days (7 percent vs. 4.5 percent), 90 days (11.4 percent vs. 8.6 percent) and one year (21 percent vs. 16 percent). "Even compared to women with an equivalent illness severity, men were more likely to die," Dr. Yende noted. "Survival differences persist up to one year after the initial hospitalization, when most patients had recovered from the pneumonia and left the hospital."

"To our knowledge, this is the largest study comparing biological response to infection between men and women. Our results suggest that immune response to infection may be an important target for interventions to reduce sex disparities in the outcomes of infections," said senior author Derek C. Angus, M.D., professor and chair in the Department of Critical Care Medicine at the University of Pittsburgh School of Medicine and principal investigator of the study.

"More studies will be needed to determine why the biological response differs between men and women," said Dr. Yende. "A clearer understanding may be useful toward designing interventions specifically targeted to men or women."

The GenIMS researchers hope to identify whether certain changes in the genes for key inflammatory molecules are associated with the risk of developing pneumonia, and the risk of progression to severe sepsis, septic shock, organ dysfunction or death. Because pneumonia is the most common cause of sepsis, patients with this infection represent an excellent clinical model for studying sepsis in a relatively homogeneous population.

In a paper published online on April 3 in The FASEB Journal, GenIMS researchers led by Drs. Yende and Angus found that people with certain gene variations associated with higher levels of macrophage migration inhibitory factor, an innate immune response regulator, were less likely to die following CAP.

"Macrophage migration inhibitory factor is a molecule that plays an important role in inflammation and has been shown to worsen outcomes in animal models of sepsis. Our results are intriguing in light of these findings and as other research groups are trying to design human studies to block this molecule in sepsis," said Dr. Yende. In future work, the researchers will continue to examine relationships between sex and gene variations in CAP, sepsis and survival.

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GenIMS is supported in part by the National Institute of General Medical Science with additional support from GlaxoSmithKline and Diagnostic Products Corporation. GenIMS was led by several investigators in the Department of Critical Care Medicine and in collaboration with other departments at the University of Pittsburgh, including Emergency Medicine, Human Genetics and Biostatistics.

Study finds more effective treatment for pneumonia following influenza

Results of St. Jude study could shape new treatments for secondary pneumonia

10 jan 2009--Scientists at St. Jude Children's Research Hospital have demonstrated a more effective treatment for bacterial pneumonia following influenza. They found that the antibiotics clindamycin and azithromycin, which kill bacteria by inhibiting their protein synthesis, are more effective than a standard first-line treatment with the "beta-lactam" antibiotic ampicillin, which causes the bacteria to lyse, or burst.

The finding is important because pneumonia, rather than the influenza itself, is a principal cause of death from influenza in children and the elderly. During pandemics—such as the one that may arise from avian influenza—up to 95 percent of influenza deaths are due to pneumonia. A bioterrorism attack using the influenza virus would likely result in the same high percentage of pneumonia deaths, according to the researchers.

The group, led by Jonathan McCullers, M.D., associate member of the St. Jude Infectious Diseases department, expect the new findings, currently demonstrated in mice, to be incorporated into standard clinical practice guidelines during the next few years.

McCullers and his colleagues published their findings in the advanced, online issue of the Journal of Infectious Diseases. The researchers based the new treatment on growing evidence that beta-lactams are relatively ineffective against secondary pneumonia because the drugs exacerbate inflammation caused by influenza.

"With severe secondary pneumonia, it has seemed that physicians do almost everything they can, and it doesn't work," McCullers said. "People still die despite treatment with antibiotics that can kill the bacteria. Our research is showing that the intense inflammatory response that is already there from the virus is amplified by the bacterial infection. And, treatment with beta-lactams releases bacterial components into the bloodstream that the immune system recognizes, triggering an inflammatory burst that can be deadly.

"Traditional first-line therapy has been based on the belief that the bacteria are bad, so we have to get rid of them as quickly as possible," McCullers said. "But what we are finding is that maybe it is the inflammation we need to worry about first, and the bacteria second. Protein synthesis inhibitors shut down the bacterial protein-making factory, and they can avoid the inflammatory burst by killing them over days instead of quickly lysing them."

In their experiments, the St. Jude researchers infected mice with a mild form of influenza that restricted itself to the lungs. After a week, the scientists infected the mice with pneumonia bacteria. This sequence mimics how humans with influenza would contract secondary pneumonia.

The researchers treated groups of the doubly infected mice with ampicillin, clindamycin, combined clindamycin and ampicillin, or azithromycin. They found that 56 percent of the mice survived with ampicillin treatment, 82 percent survived with clindamycin, 80 percent with clindamycin and ampicillin, and 92 percent with azithromycin. Significantly, while clindamycin and azithromycin both inhibit protein synthesis, azithromycin also has anti-inflammatory properties.

Ampicillin aggravated inflammation compared to clindamycin, the researchers confirmed in test tube studies. The investigators also found evidence of increased inflammation in lung cells of ampicillin-treated animals.

According to McCullers, lung tissue studies of ampicillin-treated animals also revealed the antibiotic's deleterious effects.

"We saw in those animals that, even though we were clearing their lungs of bacteria, the lungs looked just like those of animals in which the bacteria were continuing to multiply," McCullers said. "The damage process was continuing."

McCullers said he would like the new findings to influence treatment guidelines immediately for pneumonia secondary to influenza.

"The current guidelines still adhere to the theory that beta-lactams are the only drugs of choice, because it is necessary to kill the bacteria as fast as possible," he said. "However, our findings represent the first data showing that inflammation is important, and that alternative therapies such as protein synthesis inhibitors should be considered and incorporated into revised guidelines."

More broadly, McCullers said, the new findings support a growing body of evidence that treating severe pneumonia in general should take into account the inflammatory response and not just the rapid demise of bacteria.

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Other authors of this paper include Åsa Karlström and Kelli Boyd (St. Jude); and B. Keith English (Le Bonheur Children's Medical Center). This research was supported in part by the U.S. Public Health Service and ALSAC.

St. Jude Children's Research Hospital

St. Jude Children's Research Hospital is internationally recognized for its pioneering work in finding cures and saving children with cancer and other catastrophic diseases. Founded by late entertainer Danny Thomas and based in Memphis, Tenn., St. Jude freely shares its discoveries with scientific and medical communities around the world. No family ever pays for treatments not covered by insurance, and families without insurance are never asked to pay. St. Jude is financially supported by ALSAC, its fundraising organization. For more information, please visit www.stjude.org.

Pneumococcal vaccine does not appear to protect against pneumonia

06 jan 2009--Commonly used pneumococcal polysaccharide vaccines do not appear to be effective for preventing pneumonia, found a study by a team of researchers from Switzerland and the United Kingdom http://www.cmaj.ca/press/pg48.pdf.

In many industrialized countries, polysaccharide pneumococcal vaccines (PPVs) are currently recommended to help prevent pneumococcal disease in people aged 65 and over and for younger people with increased risk due to conditions like HIV. Studies have shown conflicting results regarding the efficacy of PPV.

The study, a systematic review and meta-analysis, looked at 22 clinical trials, reviews and meta-analyses and more than 100,000 participants from countries in North America as well as India, Africa, Latin America and the Caribbean. Unlike other similar studies the authors examined the reasons why different clinical trials produced different results. They found that the quality of the studies substantially affected the results. When only high quality trials were included, there was no evidence that PPVs could prevent pneumonia. The study adds to the ongoing debate around effectiveness of the vaccine.

"Policy makers may therefore wish to reconsider their current recommendations for PPV, especially where routine pneumococcal conjugate immunization has been introduced," conclude Dr. Matthias Egger from the University of Bern, Switzerland and coauthors.

However, in a related commentary http://www.cmaj.ca/press/pg18.pdf, Dr. Ross Andrews and coauthor from the Menzies School of Health Research, Darwin, Australia state that the researchers' conclusions exceed the evidence presented. They caution that there should be no change in vaccine policy in countries that recommend PPV to prevent invasive pneumococcal disease.

ICAAC-IDSA: Pneumonia Linked to Acute Coronary Syndrome

WASHINGTON, 02 nov 2008-- Patients hospitalized with bacterial pneumonia have about eight times the risk of acute coronary syndrome as those admitted for other causes, a researcher said here.
The risk is highest within 15 days of admission, said Vicente Corrales-Medina, M.D., of Baylor College of Medicine in Houston.
The association -- found in a retrospective case-control analysis -- is "so striking" it suggested a causal relationship, Dr. Corrales-Medina said at the Interscience Conference on Antimicrobial Agents and Chemotherapy, held jointly with the Infectious Diseases Society of America meeting.
"There is evidence that suggests that acute infections -- not just pneumonia -- can cause acute changes in atherosclerotic plaques," Dr. Corrals-Medina said.
Such changes, combined with effects of pneumonia such as respiratory stress, might lead to acute coronary syndromes, including unstable angina or myocardial infarction, he said.
Dr. Corrales-Medina and colleagues analyzed the records of 206 patients admitted to the Michael E. DeBakey VA Medical Center in Houston with a clinical, radiological, and bacteriological diagnosis of pneumonia from January 2000 through December 2006.
Of those cases, 144 were caused by Streptococcus pneumoniae and 62 by Haemophilus influenzae, Dr. Corrales-Medina said.
For a control group, the researchers identified 395 patients admitted with a diagnosis that was neither pneumonia nor acute coronary syndrome, who were matched by date and time of admission.
When the two groups were compared, 22 of the pneumonia patients (10.7%) had acute coronary syndrome within 15 days of admission, compared with six (1.5%) of the controls, Dr. Corrales-Medina said.
In a univariate analysis, he said, the odds ratio was 7.8, with a 95% confidence interval from 3.1 to 19.4, which was significant at P<0.001.>

A Comparative Study of Community-Acquired Pneumonia Patients Admitted to the Ward and the ICU

Marcos I. Restrepo
7 nov 2007 Background: Limited information is available on the health-care utilization of hospitalized patients with community-acquired pneumonia (CAP) depending on the location of care. Our aim was to compare the clinical characteristics, etiologies, and outcomes of patients with CAP who were admitted to the ICU with those admitted who were to the ward service.
Methods: A retrospective cohort study, at two tertiary teaching hospitals, one of which was a Veterans Affairs hospital, and the other a county hospital. Eligible subjects had been admitted to the hospital with a diagnosis of CAP between January 1, 1999, and December 31, 2001, had a confirmatory chest radiograph, and a hospital discharge International Classification of Diseases, ninth revision, diagnosis of pneumonia. Subjects were excluded from the study if they had designated "comfort measures only" or had been transferred from another acute care hospital or were nursing home patients. Bivariate and multivariable analysis evaluated 30-day and 90-day mortality as the dependent measures.
Results: Data were abstracted on 730 patients (ICU, 145 patients; wards, 585 patients). Compared to ward patients, ICU patients were more likely to be male (p = 0.001), and to have congestive heart failure (p = 0.01) and COPD (p = 0.01). ICU patients also had higher mean pneumonia severity index scores (112 [SD, 35] vs 83 [SD, 30], respectively; p = 0.02). Patients admitted to the ICU had a longer mean length of hospital stay (12 days [SD, 10 days] vs 7 days [SD, 17 days], respectively; p = 0.07), and a higher 30-day mortality rate (23% vs 4%, respectively; p < 0.001) and 90-day mortality rate (28% vs 8%, respectively; p < 0.001) compared to ward patients.
Conclusions: ICU patients present with more severe disease and more comorbidities. ICU patients stay longer in the hospital and have a much higher mortality rate when compared to ward patients. Management strategies should be designed to improve clinical outcomes in ICU patients

Zinc Helps Elderly Ward Off Pneumonia

Mon Oct 29, 7:00 PM ET
MONDAY, Oct. 29 (HealthDay News) -- Maintaining normal zinc concentrations in the blood may help prevent pneumonia in elderly nursing home residents, a new study shows.
A team at Tufts University looked at 617 people 65 and older in 33 nursing homes in the Boston area.
They found that those with normal blood zinc concentrations were about 50 percent less likely to develop pneumonia than those with low concentrations.
The study, published in the October issue of the American Journal of Clinical Nutrition, also found that people with normal zinc concentrations had a 39 percent lower rate of death from all causes.
"Not only did (people with lower zinc concentrations) have a higher risk of developing pneumonia, when they did become sick, they did not recover as quickly and required a longer course of antibiotics," corresponding author Simin Nikbin Meydani, director of the nutritional immunology laboratory at the U.S. Department of Agriculture's Human Nutrition Research Center on Aging at Tufts, said in a prepared statement.
The Tufts researchers took blood samples from the participants at the start and conclusion of the one-year study. All the participants received daily supplements containing 50 percent of the recommended dietary allowance of several vitamins and minerals, including zinc, for one year.
"Zinc is already known to strengthen the immune system; however, there needs to be further investigation of zinc and its effect on pneumonia development and prevention in nursing homes. The next step would be a clinical trial," Meydani said.
Red meat, poultry, whole grains, beans, dairy products, and oysters are examples of foods that provide zinc.
More information
The American Lung Association has more about pneumonia.

Adequate Zinc Levels Help Quell Pneumonia in Elderly

BOSTON, Oct. 23 -- For nursing home elderly, a little zinc every day may stave off pneumonia or lessen its severity and duration, nutrition researchers here reported. In an observational study, they found that those of nearly 600 nursing home residents (ages 84.6 + 7.6) with normal serum zinc concentrations had lower occurrence rates of pneumonia, fewer new prescriptions for antibiotics, a shorter duration of pneumonia, and fewer days of antibiotic use compared with patients who had low zinc levels.
Patients with normal zinc levels also had a 39% lower all-cause mortality rate than patients with low levels, reported Simin N. Meydani, D.V.M., Ph.D., of the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts, and colleagues, in the October issue of the American Journal of Clinical Nutrition.
"Results from our study indicate that supplementation with <80 mg of zinc daily might reduce mortality in the elderly," they wrote.
Other studies have shown a reduced occurrence rate of all-cause mortality in older patients and in other populations, the investigators noted. In the Age-Related Eye Disease Study, for example, the risk of death was reduced by 27% among those who received 80 mg of zinc daily in a supplement.
"In addition, zinc supplementation has been shown to reduce overall mortality by as much as 51% in children with diarrhea and by as much as 68% in infants born full-term and those small-for-gestational age," they wrote.
The authors conducted an observational study to determine whether serum zinc concentrations in elderly nursing home residents are associated with the incidence and duration of pneumonia, total antibiotic use and duration of use, and pneumonia-associated and all-cause mortality.
The participants were residents of 33 Boston nursing homes who were part of a one-year randomized, double-blind, placebo-controlled trial of vitamin E supplementation. As part of that trial, participants all were given daily doses of 50% of the recommended dietary allowance of essential vitamins and minerals, including zinc.
In the analysis, the Tufts group included 578 participants with baseline zinc level measurements and 420 with end-of-study values, including seven with only end-of-study levels. The cutoff points they chose were less than 70 µg/dL to indicate low serum zinc concentrations, and 70 µg/dL or higher to indicate normal levels.
"Although there is no consensus that zinc status can be easily defined by serum zinc values, it is the most widely used biochemical indicator of zinc status and is the only biochemical indicator of zinc status for which adequate reference data are available," the authors wrote. "In addition, several studies in the elderly have shown that serum zinc concentrations do respond to zinc supplementation."
The investigators found that compared with the patients who had low zinc levels, patients with normal levels had a 53% lower rate of death from pneumonia, although this difference was not statistically significant (P=0.198). However, the all-cause mortality rate was 39% lower among patients with normal zinc levels, and this difference was significant (P=0.049).
When the authors controlled for between-group differences in congestive heart failure and other potential confounders, they found that the statistical significance of the differences in mortality rates remained largely unchanged.
Serum zinc concentrations at the end of the study were strongly associated with the incidence and duration of pneumonia and with the number of new antibiotic prescriptions and days of antibiotic use (P<0.004 for all).
Both the occurrence rate of pneumonia and the total number of new antibiotic prescriptions to treat pneumonia were about 50% lower in those with end serum zinc concentrations of at least 70 µg/dL than in those with lower concentrations.
Duration of pneumonia was 3.9 days shorter and days of antibiotic use were 2.6 fewer among patients with normal zinc levels versus low zinc, and these differences remained significant when the authors controlled for various factors, including baseline serum albumin and change in serum albumin concentrations.
The authors concluded "that an adequately powered randomized, double-blind, controlled trial seems to be the likely next step. Such a study is needed to determine the efficacy of zinc supplementation as a potential low-cost intervention to reduce morbidity and mortality due to pneumonia in this vulnerable population."
The study was supported by the National Institute on Aging, the USDA, and a grant for preparation of the study capsules from Hoffmann-La Roche Vitamins and Fine Chemicals Division. All authors declared that they had no conflicts of interest. Primary source: American Journal of Clinical NutritionSource reference: Meydani SN, et al "Serum zinc and pneumonia in nursing home elderly" Am J Clin Nutr 2007; 86: 1167-73.