2014

People with moderate-to-severe vitamin D deficiencies are significantly more likely to develop Alzheimer’s disease or other forms of dementia than those who have an adequate supply of the vitamin in their body, a new study has found.

Researchers, led by David J. Llewellyn at the University of Exeter Medical School, found that adults who suffered from a moderate deficiency of vitamin D had a 53 percent higher risk of some form of dementia, while the risk increased 125 percent in those with severe deficiencies. People moderately deficient in vitamin D were 69 percent more likely to develop Alzheimer’s-caused dementia, while those severely deficient raised the risk to 122 percent.

The team discovered what appear to be clear threshold levels for brain health using standard medical measurements of concentration in the blood. The risk of dementia appears to rise for people with vitamin D blood levels below 25 nanomoles per liter, while vitamin D levels above 50 nanomoles appear to be good levels for brain health.

Llewellyn said that although the international team of researchers expected to find a link between vitamin D deficiency and dementia, the strong correlation between the two was surprising. He said further study was necessary to determine whether consuming oily fish or vitamin D supplements might prevent Alzheimer’s disease.

Alzheimer’s disease is the leading form of dementia, affecting more than 5 million people in the United States. That number is expected to reach 16 million by 2050 as the population ages.

Vitamin D, which helps the body use calcium, is created when skin is exposed to sunshine. Milk is often fortified with the vitamin, and it is also found in fatty fish and other foods.

Researchers in the Exeter study noted that laboratory experiments have shown that vitamin D may play a role in ridding cells of beta-amyloid plaques, an abnormality that distinguishes Alzheimer’s.

“It seems to be that vitamin D was actually helping to break down and take away those protein abnormalities,” Llewellyn said Wednesday in an interview.

The study, funded in part by the Alzheimer’s Association, appeared Wednesday in Neurology, the medical journal of the American Academy of Neurology.

Source: Washington Post

PHC’s Dr. Elting appeared on News Channel 8 Monday with Bruce Depuyt to discuss Ebola virus. Depuyt asked Dr. Elting, an infectious disease specialist, for insight into the virus and the pair of American patients who just arrived in the United States for treatment.

From the broadcast:

We begin this time with the latest on the Ebola crisis in Africa. A new report just out overnight finds 826 people have died from the virus. There’s been a surge of cases in Liberia and Sierra Leone. The American doctor suffering from Ebola is now being treated in a Georgia hospital and a colleague is on her way home.

Joining us now is Dr. Jeffrey Elting. Dr. Elting is the Medical Director of the Presidential Healthcare Center in the district. Before taking his current position, he coordinated bioterrorism responses for the DC Hospital Association.

“It’s a hemorrhagic fever virus,” Dr. Elting said. “There have been over 40 outbreaks over the last 40 years, mostly in Africa, and with that comes a high death rate.”

“You have to take into account that, in some of those areas, they don’t have the assets to provide the correct isolation and the correct care.”

Dr. Elting spoke on the treatment the two American patients– Dr. Kent Brantly and Nancy Writebol– will receive at Emory Hospital in Atlanta. He also answered questions from viewers calling into the show.

“It’s transmitted by bodily fluids. It’s not transmitted by respiratory droplets like the flu or a cold,” Dr. Elting said. “Once a person gets infected, there’s an incubation period between the time they get exposed to the time they actually have symptoms. That can range anywhere from two to 21 days.”

“The initial symptoms are somewhat flu-like. They get muscle aches, headaches, fever, don’t feel well, they have vomiting. But it is a hemorrhagic virus. It causes hemorrhaging, in which case you’ll get things like bleeding into your eyes, bleeding into your lungs, bleeding into your internal organs. Generally, that’s what your cause of death is.”

View the whole interview here.

Running for only a few minutes a day or at slow speeds may significantly reduce a person’s risk of death from cardiovascular disease compared to someone who does not run, according to a study published today in the Journal of the American College of Cardiology.

Exercise is well-established as way to prevent heart disease and it is component of an overall healthy life, but it is unclear whether there are health benefits below the level of 75 minutes per week of vigorous-intensity activity, such as running, recommended by the U.S. government and World Health Organization.

Researchers studied 55,137 adults between the ages of 18 and 100 over a 15-year period to determine whether there is a relationship between running and longevity. Data was drawn from the Aerobics Center Longitudinal Study, where participants were asked to complete a questionnaire about their running habits. In the study period, 3,413 participants died, including 1,217 whose deaths were related to cardiovascular disease. In this population, 24 percent of the participants reported running as part of their leisure-time exercise.

Compared with non-runners, the runners had a 30 percent lower risk of death from all causes and a 45 percent lower risk of death from heart disease or stroke. Runners on average lived three years longer compared to non-runners. Also, to reduce mortality risk at a population level from a public health perspective, the authors concluded that promoting running is as important as preventing smoking, obesity or hypertension. The benefits were the same no matter how long, far, frequently or fast participants reported running. Benefits were also the same regardless of sex, age, body mass index, health conditions, smoking status or alcohol use.

The study showed that participants who ran less than 51 minutes, fewer than 6 miles, slower than 6 miles per hour, or only one to two times per week had a lower risk of dying compared to those who did not run. DC (Duck-chul) Lee, Ph.D., lead author of the study and an assistant professor in the Iowa State University Kinesiology Department in Ames, Iowa, said they found that runners who ran less than an hour per week have the same mortality benefits compared to runners who ran more than three hours per week. Thus, it is possible that the more may not be the better in relation to running and longevity.

Researchers also looked at running behavior patterns and found that those who persistently ran over a period of six years on average had the most significant benefits, with a 29 percent lower risk of death for any reason and 50 percent lower risk of death from heart disease or stroke.

“Since time is one of the strongest barriers to participate in physical activity, the study may motivate more people to start running and continue to run as an attainable health goal for mortality benefits,” Lee said. “Running may be a better exercise option than more moderate intensity exercises for healthy but sedentary people since it produces similar, if not greater, mortality benefits in five to 10 minutes compared to the 15 to 20 minutes per day of moderate intensity activity that many find too time consuming.”

The outbreak of the extraordinarily lethal Ebola virus has worsened in West Africa, with the contagion showing no sign of coming under control, prompting the Centers for Disease Control and Prevention on Thursday to warn Americans to avoid nonessential travel to Guinea, Liberia and Sierra Leone.

In addition to raising the health threat level to 3, the agency’s highest level, the CDC said it is sending 50 infectious-disease experts to the affected region and will assist airports in Africa in screening outbound passengers. The CDC had already alerted U.S. hospitals and doctors to be on the lookout for signs of Ebola fever and to question patients about their recent travel history and contacts.

“This is a tragic, painful, dreadful, merciless virus. It’s the largest, most complex outbreak that we know of in history,” said CDC director Tom Frieden in a news briefing Thursday.

A patient who was infected with the virus in Africa is expected to be treated at Emory University Hospital in Atlanta within several days, the university said in a statement Thursday. The patient, his or her identity undisclosed, will be treated at a special containment unit set up in collaboration with the CDC to treat people exposed to serious infectious diseases. A spokeswoman said she did not know when the patient will arrive or who the patient is. CNN, citing an unnamed source, reported that a plane left Cartersville, Ga., Thursday evening to evacuate two U.S. charity workers in Liberia infected with Ebola.

It would be the first time a patient infected with Ebola has been treated in the United States, according to a CDC spokeswoman.

“Every precaution is being taken to move those infected safely and securely, to provide critical care en route and to maintain strict isolation upon arrival in the United States,” said the CDC spokeswoman, Barbara Reynolds. “The safety and security of U.S. citizens is our highest priority. These are U.S. citizens who are returning to the United States for medical care. They are being returned under strict medical protocols for infectious diseases.”

Frieden warned that this outbreak will take at least three to six months to suppress, under the best of circumstances. There is no cure or treatment for the disease, in which the virus replicates rapidly throughout the body, causing multiple organ failure and, typically, death in a matter of days. In the latest outbreak, about 6 of 10 people infected have died.

Vaccine research is progressing, and human trials of a possible vaccine could begin as soon as September, Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said Thursday. The CDC’s Frieden said a vaccine is at least a year away.

That leaves officials with low-tech tools for battling the virus as it rages across West Africa and threatens to spread to other continents. Doctors and disease detectives need to find victims and quarantine them. They have to track down people with whom they’ve been in contact. Caregivers have to be meticulous in wearing formidable protective gear. Family members must be instructed on how to handle the bodies of the deceased.

That’s been the formula for stopping all previous outbreaks in Africa, with the hot virus essentially burning itself out.

“Most of those little outbreaks of varying sizes would be contained because they were in rural areas, where health workers could isolate the people and ultimately get the villages to stop doing the things that propagated it,” Fauci said.

But this outbreak is trickier, he said, because it covers a larger region and several countries with porous borders and weak health-care systems. At the same time, Fauci and other health officials say that Americans should not fear that the epidemic will take hold in the United States. That’s because Ebola, deadly as it is, is contagious only when a patient is sick with symptoms of the disease. The virus is spread by direct contact with bodily fluids after the symptoms appear.

A person who becomes infected will not show symptoms for five to 10 days, sometimes as long as three weeks. In that incubation period, the person isn’t contagious. The symptoms, when they come on, are severe, and U.S. officials are confident that they can isolate any patients should Ebola manage to spread here.

“Ebola poses little risk to the U.S. general population,” Frieden said.

“There is certainly a possibility that someone might get on a plane who is infected in Sierra Leone or Liberia and come to the United States. But the chance of it being spread here the way you are seeing there is extraordinarily low, to the point that the CDC and me and other officials feel confident that there’s not going to be an outbreak here,” Fauci said.

The World Health Organization is not recommending any travel restrictions or closure of borders at this time. The International Air Transport Association said it will follow WHO’s lead on travel restrictions.

“What is key about this disease is that if people aren’t showing symptoms, they’re not contagious,” said Jason Sinclair, a spokesman for IATA.

What sets Ebola apart from other viruses is its lethality. Even the deadliest strain of influenza, for example, kills no more than 1 percent of patients. But some areas of Africa with poor health care have been known to have a 90 percent mortality rate from Ebola during previous outbreaks.

Since the first report of the deadly virus surfaced in March, there have been 1,323 cases reported and 729 deaths, according to the WHO.

One death attributed to Ebola has been reported in Nigeria. Patrick Sawyer, 40, a Liberia-born American citizen who worked for the Liberian Finance Ministry, fell ill while traveling from Liberia to Lagos, Nigeria, with stops in Ghana and Togo, according to the Associated Press. He died in Lagos on July 25. He reportedly had been caring for his sister, who had died of Ebola several weeks earlier.

Governments across the globe, from Washington to Europe to Hong Kong, are gauging the appropriate response. White House deputy press secretary Eric Schultz said President Obama had been briefed about the Ebola outbreak. He said the Ebola crisis won’t affect next week’s summit of African leaders being held in Washington.

“I would tell you that we’re working closely with regional governments to stem the spread of the virus. We have no plans to change any elements of the U.S.-Africa Leaders Summit, as we believe all air travel continues to be safe here,” Schultz said.

About 10,000 people arrive in the United States from the affected region of Africa every three to four months, Frieden said. The CDC has protocols in place to protect against further spread of the disease. These include notification to CDC of ill passengers on a plane before arrival, investigation of ill travelers and, if necessary, quarantine. CDC also provides guidance to airlines for managing ill passengers and crew and for disinfecting aircraft.

The CDC already has a dozen staffers working in West Africa. They are operating in regions that have been torn by civil war. Frieden said one CDC group was driven away after a hostile reception and retreated to a neighboring country, though he did not give details. There have been a couple of dozen outbreaks of Ebola previous to this one, with the first in 1976. This outbreak began in Guinea in March.

Two American aid workers in Monrovia, Liberia, have contracted the virus and are in grave condition, according to a statement released by the Christian aid group Samaritan’s Purse. The group said that Kent Brantly, a physician, was offered an experimental serum sent to the country Wednesday, but that there was only enough for one person, so he asked that it be given to Nancy Writebol, a missionary worker with the Charlotte-based missionary organization SIM. However, a SIM spokesperson said both aid workers were given the serum.

“There are efforts to bring her back,” said Palmer Holt, a spokesman for SIM. “We’re feeling optimistic about the process of relocating non-essential personnel and the two patients.”

The group is evacuating some workers from Liberia, but medical staff members have been left behind to treat patients. The outbreak has prompted the Peace Corps to temporarily remove its 102 volunteers in Guinea, 108 in Liberia and 130 in Sierra Leone.

Sierra Leone has declared a state of emergency and is mobilizing police and the military to quarantine the epicenters of the disease. Sierra Leone’s top Ebola doctor fell victim to the virus and died.

“It is very worrying to hear any reports of international agencies pulling out at the time when there is an absolute need for additional medical experts and health workers to get control of this outbreak,” said Jason Cone, communications director at Doctors Without Borders. The organization said it has 552 staffers on the ground in the three affected countries and it desperately needs more resources to battle the contagion.

Michael Osterholm, director of the University of Minnesota’s Center for Infectious Disease Research and Policy, noted that Africa is a different place than it was 25 years ago. Africans travel much more often now, and this mobility boosts the chances for Ebola to spread.

The CDC’s Frieden expressed confidence that officials will get the situation under control eventually.

“Though it will not be quick, and it will not be easy, we do know how to stop Ebola,” Frieden said. “This is a marathon, not a sprint.”

Source: Washington Post

The U.S. government recommends that American adults eat 5 to 13 servings of fruits and vegetables depending on your age, gender, and activity level, but a new Harvard School of Public Health study suggests we don’t get additional health benefits if we eat more than five servings a day.

After analyzing 16 studies involving 833,000 participants who filled out dietary surveys, the researchers from Harvard and China discovered that each daily serving of produce was associated with a five percent lower risk of dying from heart disease or cancer during the studies, which lasted up to 25 years. Eating five servings a day, for example, lowered the risk of dying by 25 percent — but so did eating six or seven servings, according to the results published Tuesday in the British Medical Journal.

“The reduction in mortality plateaued at five [servings] a day, and five a day is a good target to achieve maximum health benefits in reducing mortality,” said study coauthor Frank Hu, a professor of nutrition and epidemiology at the Harvard School of Public Health, via email from China.

Is there any harm to over-indulging on the kale, celery, and sliced strawberries?

Likely not, since the research didn’t find any negative health effects in those who ate six or more servings a day, according to Hu. What’s more, it couldn’t prove that eating five servings of produce a day actually prevented deaths, but rather found it was statistically associated with a lower mortality risk.

Still, it’s a smart move to “diversify plant-based foods,” Hu said, adding nuts, legumes, and whole grains to those salads. That will ensure that you get a wider range of nutrients, which often interact in the body to have a synergistic effect on disease prevention.

Source: Boston Globe

With nearly four in five older Americans living with multiple chronic medical conditions, a new study by researchers at Johns Hopkins Bloomberg School of Public Health finds that the more ailments you have after retirement age, the shorter your life expectancy. The analysis, one of the first to examine the burden of multiple chronic conditions on life expectancy among the elderly, may help explain why increases in life expectancy among older Americans are slowing.

A report on the findings, based on an analysis of 1.4 million Medicare enrollees, appears in the August issue of the journal Medical Care.

“Living with multiple chronic diseases such as diabetes, kidney disease and heart failure is now the norm and not the exception in the United States,” says Eva H. DuGoff, a recent PhD recipient at the Johns Hopkins Bloomberg School of Public Health and lead author of the report. “The medical advances that have allowed sick people to live longer may not be able to keep up with the growing burden of chronic disease. It is becoming very clear that preventing the development of additional chronic conditions in the elderly could be the only way to continue to improve life expectancy.”

For their analysis, researchers used the Medicare 5% sample, a nationally representative sample of Medicare beneficiaries, enrolled as of January 1, 2008, which included 21 defined chronic conditions and the records of nearly 1.4 million people 67 and older.

Life expectancy in the U.S. is rising more slowly than in other parts of the developed world and many blame the obesity epidemic and its related health conditions for the worsening health of the American population.

The analysis found that, on average, a 75-year-old American woman with no chronic conditions will live 17.3 additional years (that’s to more than 92 years old). But a 75-year-old woman with five chronic conditions will only live, on average, to the age of 87, and a 75-year-old woman with 10 or more chronic conditions will only live to the age of 80. Women continue to live longer than men, while white people live longer than black people.

It’s not just how many diseases you have, but also what disease that matters. At 67, an individual with heart disease is estimated to live an additional 21.2 years on average, while someone diagnosed with Alzheimer’s disease is only expected to live 12 additional years.

On average, life expectancy is reduced by 1.8 years with each additional chronic condition, the researchers found. But while the first disease shaves off just a fraction of a year off life expectancy for older people, the impact grows as the diseases add up.

“We tend to think about diseases in isolation. You have diabetes or you have heart failure. But many people have both, and then some,” says senior author Gerard F. Anderson, PhD, a professor in the Department of Health Policy and Management at the Johns Hopkins Bloomberg School of Public Health. “The balancing act needed to care for all of those conditions is complicated, more organ systems become involved as do more physicians prescribing more medications. Our system is not set up to care for people with so many different illnesses. Each one adds up and makes the burden of disease greater than the sum of its parts.”

The researchers say their findings could be useful to Social Security and Medicare planners as they make population and cost predictions for the future. Policymakers are facing a different landscape as so many more people are living with multiple chronic conditions than before: 60 percent of those 67 and older in the U.S. have three or more of these diseases, the researchers found. Eventually, there may be a tipping point, when the medical advances that have boosted life expectancy for so long can no longer keep pace with the many illnesses people are collecting as they age.

“We already knew that living with multiple chronic conditions affects an individual’s quality of life, now we know the impact on quantity of life,” DuGoff says. “The growing burden of chronic disease could erase decades of progress. We don’t want to turn around and see that life expectancy gains have stopped or reversed.”

“Multiple Chronic Conditions and Life Expectancy, A Life Table Analysis” was written by Eva H. DuGoff, PhD; Vladimir Canudas-Romo, PhD; Christine Buttorff; Bruce Leff, MD; and Gerard F. Anderson, PhD. The study was supported by the American Insurance Group.

Source: Johns Hopkins

Men who have a vasectomy may be at increased risk for aggressive prostate cancer, a new study suggests.

But the risk is comparatively small, the researchers acknowledged. And several urologists not involved with the study said more research is needed to determine if the study findings are truly accurate.

For the study, Harvard researchers analyzed data from more than 49,400 American men who were followed for 24 years, starting in 1986. During that time, 6,023 cases of prostate cancer were diagnosed among the men, including 811 fatal cases.

The 25 percent of the men in the study who’d had a vasectomy had a 10 percent increased risk of developing prostate cancer, according to the study published online July 7 in the Journal of Clinical Oncology.

Vasectomy was not linked with an increased risk of low-grade prostate cancer. But it was associated with a 20 percent higher risk of advanced prostate cancer and a 19 percent greater risk of fatal prostate cancer, respectively, the study authors said.

Even among men who had regular prostate-specific antigen (PSA) screening tests for prostate cancer, those who had a vasectomy were 56 percent more likely to develop fatal prostate cancer. This link was strongest among men who had a vasectomy at a younger age.

However, the absolute risk of developing deadly prostate cancer was small, the study authors noted — 16 of every 1,000 men.

“This study follows our initial publication on vasectomy and prostate cancer in 1993, with 19 additional years of follow-up and tenfold greater number of cases. The results support the hypothesis that vasectomy is associated with an increased risk of advanced or lethal prostate cancer,” study co-author Lorelei Mucci, associate professor of epidemiology at the Harvard School of Public Health, said in a university news release.

About 15 percent of men in the United States have a vasectomy. Prostate cancer is the second leading cause of death among American men, although most men diagnosed with the disease don’t die from it.

“The decision to opt for a vasectomy as a form of birth control is a highly personal one and a man should discuss the risks and benefits with his physician,” study co-author Kathryn Wilson, a research associate in the department of epidemiology, said in the university news release.

Dr. Louis Kavoussi is chairman of urology at North Shore-LIJ Health System in New Hyde Park, N.Y. He said: “I would be cautious about applying these findings to clinical practice right now. This is not like cigarette smoking causing a large number of people to develop lung cancer. This is a small increase in the risk of prostate cancer. I think further studies really need to be mandated in a better controlled fashion.

“There are a whole host of potential unknown reasons why this potentially could be real,” he added. “On the other hand, this is a retrospective study — a backwards-looking study over many, many years, and the increased risk is small. So can this be an error in statistics? There are many papers over the years that don’t show a correlation with this.”

Dr. Aaron Katz, chairman of urology at Winthrop-University Hospital in Mineola, N.Y., suggested that men who’ve undergone a vasectomy may simply have their cancers caught more often because they see their doctor more often.

“Several studies have looked at the association between vasectomy and prostate cancer. It is well known that men who have had a vasectomy are more likely to be seen more frequently by urologists in follow-up than men who never had a vasectomy, and will undergo more frequent PSA testing,” he said.

The Harvard researchers said they were able to compensate for factors such as more frequent visits to doctors before reaching their conclusions.

Kavoussi added: “The implications of this study, if it becomes dogma, can be quite profound in society. All of a sudden birth control has been pushed entirely onto women. There are potential side effect issues with birth control for women as well.”

Support for the study was provided by grants from the U.S. National Cancer Institute, among other sources.

Source: CBS News

As temperatures increased above 50°F (10°C) in several large U.S. cities, risk of kidney stones also increased significantly researchers said.

A study of 60,433 privately insured patients across five cities — Atlanta, Chicago, Dallas, Los Angeles, and Philadelphia — found that the maximum risk for kidney stone presentation occurred within 3 days of a high daily temperature and was likely mediated by an effect on patients’ hydration.

The risk was statistically significant in all cities except Los Angeles, according to the paper, published online in Environmental Health Perspectives.

Cumulative relative risks for a mean daily temperature of 86°F (30°C) versus 50°F were:

• Atlanta (1.38, 95% CI 1.07-1.79)
• Chicago (1.37, 95% CI 1.07-1.76)
• Dallas (1.36, 95% CI 1.10-1.69)
• Los Angeles (1.11, 95% CI 0.73-1.68)
• Philadelphia (1.47, 95% CI 1.00-2.17)

The five cities represent climates in which 30% of the world’s population lives, according to study author Gregory Tasian, MD, MSc, at the University of Pennsylvania, and colleagues.

Using a time series design and distributed lag nonlinear model, researchers collected private health insurance claims data from 2005-2011 as well as weather data for the selected cities. Tasian and colleagues examined presentation for kidney stones within a 20-day window of temperature exposure.

Cases tended to occur within a few days after episodes of extreme temperature, with a first peak at about 2 to 3 days and a second at 4 to 6 days.

“We were expecting to find a short lag time between heat and presentation, so it wasn’t really surprising that the lag time was detected within a week,” Tasian told MedPage Today.

Tasian and colleagues hypothesized that dehydration is the causal mechanism between the effect of heat and stone presentation. When patients who are already at risk get dehydrated, calcium and uric acid become more supersaturated, and calcium stones begin to form, they said.

“It’s all linked to fluid. Saying heat leads to fluid loss would be the direct link,” said Allan Jhagroo, MD, a professor of nephrology at the University of Wisconsin who was not associated with the study.

The researchers also hypothesized that the hotter weather may have led to stone formation in patients exposed to hotter weather who would have normally developed stones at a future time.

Colder weather was associated with a relative risk in Atlanta, Chicago, and Philadelphia, perhaps because patients stay indoors where it can be hotter. It’s also conceivable that hydration may suffer during extremes of cold (when indoor humidity, which was not measured in the study, is usually low) as well as hot weather.

Outdoor humidity was measured, but was not found to be a predictor for kidney stones.

The researchers also suggested that the number of hot days in a year is probably a better indicator of kidney stone risk than mean annual temperature. Atlanta, for example, had almost twice the rate of kidney stones compared with Los Angeles but had a similar mean temperature. It had, though, on average 53 days a year in which the daily mean temperature was higher than 80°F. Los Angeles had only 10.

Dallas had 324 days hotter than 86°F during the period, 20 times more than such days in Atlanta, the next closest city. But it had the same risk increase. Tasian and colleagues suggested that the population of Dallas may have adapted to the local climate, spending more time indoors and drinking more fluids. They also noted that their data were sparse for extreme weather, and their statistical methods may have flattened the associations somewhat.

A previous study reported by MedPage Today found that, as temperatures across the U.S. increase because of climate change, the prevalence of kidney stones may be expected to grow. Tasian said that more research needs to be done to see how the risk of kidney stones may change with temperature increases.

The authors acknowledged several limitations to the study. They had no data on individuals’ actual exposure to outdoor temperatures, which would vary. All the patients had commercial insurance and may spend more time indoors, with air conditioning, than those with public or no insurance. It is also possible that temperature differentially affects subgroups such as older versus younger patients.

Additionally, the research was concerned only with presentation at the hospital and not stone formation.

Jhagroo suggested that this left open the question of whether “warmer weather leads to passage, or warmer weather leads to both formation and passage.”

Source: Med Page Today

Sleep disturbances such as apnea may increase the risk of Alzheimer’s disease, while moderate exercise in middle age and mentally stimulating games, such as crossword puzzles, may prevent the onset of the dementia-causing disease, according to research to be presented Monday.

The findings — which are to be introduced during the six-day Alzheimer’s Association International Conference in Copenhagen — bolster previous studies that suggest sleep plays a critical role in the aging brain’s health, perhaps by allowing the body to cleanse itself of Alzheimer’s-related compounds during downtime. The studies also add to a growing body of literature that suggests keeping the brain busy keeps it healthy.

The battle against Alzheimer’s disease has become more urgent for the United States and other developing nations as their populations turn increasingly gray. The disease is the leading cause of dementia in older people and afflicts more than 5 million Americans. At its current pace, the number is expected to soar to 16 million people by 2050.

In 2012, the United States adopted a national plan to combat the disease and the Group of Eight nations last year adopted a goal of providing better treatment and prevention by 2025.

Erin Heintz, a spokeswoman for the Alzheimer’s Association, said U.S. government funding to combat the disease now stands at about $500 million a year. To reach its 2025 goal, th e United States should be spending $2 billion a year, she said.

The sleep study, conducted by University of California at San Francisco researchers on a large sample of veterans, found that those with diagnosed sleep disorders such as apnea or insomnia were 30 percent more likely to suffer dementia than veterans without such problems. Veterans who suffered from sleep problems and post-traumatic stress disorder (PTSD) had an 80 percent greater risk.

“I would say that this is another important study showing this link between sleep and subsequent diagnosis of dementia,” Kristine Yaffe, a psychiatry professor at UCSF who heads its Dementia Epidemiology Research Group, said in a telephone interview. She said her study’s findings benefited from having such a large sample of participants: Researchers used eight years of records on 200,000 veterans, most of whom were male and 55 or older.

It is well known that people afflicted with Alzheimer’s suffer from sleep disorders, Yaffe said, but further research is necessary to determine whether sleep disturbance heightens the risk of getting dementia or is a symptom.

In a separate study, researchers at the Wisconsin Alzheimer’s Institute and the Wisconsin Alzheimer’s Disease Research Center wanted to find out whether middle-aged people who engage in mentally stimulating activities might reduce their risk of cognitive impairment and dementia. Forty percent of the subject group carried the gene linked to Alzheimer’s and 74 percent had a parent with the illness, two factors known to increase the risk of getting the disease.

The researchers studied 329 participants — 69 percent of whom were women, whose mean age was about 60 — to find out how often the participants read books, visited museums, played games such as checkers or worked on puzzles.

The subjects also underwent a battery of tests, including MRI brain scans to measure the volume of those regions commonly afflicted by Alzheimer’s.

For purposes of the study, researchers focused on the group’s game-playing habits to see if the frequency of playing games was related to better brain and cognitive health.

Stephanie Schultz, lead author of the study, said that although more research is necessary to know for sure, the findings suggest that stimulating the brain with ordinary diversions such as crossword puzzles may help some people preserve brain tissue and cognitive functions that are vulnerable to dementia. Those who reported a higher frequency of playing games also had greater brain volume in regions affected by Alzheimer’s, such as the hippocampus.

“The more they play these types of games, the better it is for … brain health,” she said.

One reason could be that game-playing involves more complicated processes across multiple regions of the brain, compared with more passive forms of mental engagement, the researchers said.

“It’s very clear it’s a different quality of mental engagement when you’re playing games of skill than when you’re reading a book,” said Ozioma Okonkwo, an assistant professor of medicine at the University of Wisconsin School of Medicine and senior author of the study. “To win a card game, you have to judge, you have to plan, you have to do something, you have to remember what the last player played.”

Okonkwo said the results were exciting particularly because they held true for people with a family history of Alzheimer’s and a genetic disposition to the disease.

“These individuals already have two strikes against them,” he said.

Similarly, a three-year study of people with mild cognitive impairment by researchers at the Mayo Clinic Study of Aging suggests that moderate physical exercise in middle age could decrease the risk that their cognitive deficits progress to dementia. The study looked at the timing of regular exercise — undertaken either in midlife between the ages of 50 and 65, or later in life, from age 70 and up — and its relationship to the onset of dementia in a group of 280 elderly people. Their median age was 81.

Oddly, however, the association did not hold for people who engaged in light or vigorous exercise in middle age or for any level of physical activity later in life.

On a similarly counterintuitive note, another study suggested that high blood pressure among people at least 90 years old — “the oldest old” — may protect against cognitive impairment. Researchers at the University of California at Irvine said that although hypertension is believed to increase the risk of Alzheimer’s and dementia for middle-aged people, the risk may shift with time.

Their study, which examined 625 people who are 90 or older, found that people who were diagnosed with high blood pressure between the ages of 80 and 89 had a significantly lower risk of dementia. People with hypertension after the age of 90 had an even lower risk, the researchers said.

(Source: Washington Post)

Sedentary lifestyle and not caloric intake may be to blame for increased obesity in the US, according to a new analysis of data from the National Health and Nutrition Examination Survey (NHANES). A study published in the American Journal of Medicine reveals that in the past 20 years there has been a sharp decrease in physical exercise and an increase in average body mass index (BMI), while caloric intake has remained steady. Investigators theorized that a nationwide drop in leisure-time physical activity, especially among young women, may be responsible for the upward trend in obesity rates.

By analyzing NHANES data from the last 20 years, researchers from Stanford University discovered that the number of US adult women who reported no physical activity jumped from 19.1% in 1994 to 51.7% in 2010. For men, the number increased from 11.4% in 1994 to 43.5% in 2010. During the period, average BMI has increased across the board, with the most dramatic rise found among young women ages 18-39.

“These changes have occurred in the context of substantial increases in the proportion of adults reporting no leisure-time physical activity, but in the absence of any significant population-level changes in average daily caloric intake,” explains lead investigator Uri Ladabaum, MD, MS, Associate Professor of Medicine (Gastroenterology and Hepatology), Stanford University School of Medicine. “At the population level, we found a significant association between the level of leisure-time physical activity, but not daily caloric intake, and the increases in both BMI and waist circumference.”

The study looked at the escalation of obesity in terms of both exercise and caloric intake. While investigators did not examine what types of foods were consumed, they did observe that total daily calorie, fat, carbohydrate, and protein consumption have not changed significantly over the last 20 years, yet the obesity rate among Americans is continuing to rise.

Researchers also tracked the rise in abdominal obesity, which is an independent indicator of mortality even among people with normal BMIs. Abdominal obesity is defined by waist circumference of 88 cm (34.65 in) or greater for women and 102 cm (40.16 in) or greater for men. Data showed that average waist circumference increased by 0.37% per year for women and 0.27% per year for men. Just like the rise in average BMIs, the group most affected by increased rates of abdominal obesity was women.

“The prevalence of abdominal obesity has increased among normal-weight women and overweight women and men,” observes Dr. Ladabaum. “It remains controversial whether overweight alone increases mortality risk, but the trends in abdominal obesity among the overweight are concerning in light of the risks associated with increased waist circumference independent of BMI.”

When Ladabaum et al grouped respondents to the most recent NHANES survey by race/ethnicity and age, they found that more than 50% of the workforce-aged adults in eight demographic subgroups reported no leisure-time physical activity. The following chart displays the results and highlights the differences between the 1994 survey results and those collected in 2010 (albeit, with slightly different survey methods). According to this data, women, and black and Mexican-American women in particular, showed the greatest decreases in reported exercise.

While increased caloric intake is often blamed for rising rates of obesity, no association between these was found in this study; in contrast, an association was found between the trends over time for lack of physical activity and high BMI numbers. “Our findings do not support the popular notion that the increase of obesity in the United States can be attributed primarily to sustained increase over time in the average daily caloric intake of Americans,” concludes Dr. Ladabaum. “Although the overall trends in obesity in the United States are well appreciated and obesity prevalence may be stabilizing, our analyses highlight troublesome trends in younger adults, in women, and in abdominal obesity prevalence, as well as persistent racial/ethnic disparities.”

There is no easy answer in our ongoing battle against obesity, but identifying the link between the drop in physical activity and increased BMIs, as well as the groups particularly affected, can assist public health officials to develop targeted, effective interventions. In an accompanying commentary Pamela Powers Hannley, MPH, Managing Editor, the American Journal of Medicine, notes, “If we as a country truly want to take control of our health and our health care costs, the Ladabaum et al paper should be our clarion call. From encouraging communities to provide safe places for physical activity to ensuring ample supply of healthy food to empowering Americans to take control of their health, we must launch a concerted comprehensive effort to control obesity.”