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8 January 2011

Fishy diet comes with lower risk of stroke

(Reuters Health) - Women who eat more than three servings of fish per week are less likely to experience a stroke, a new study suggests.

Specifically, fish-lovers in Sweden were 16 percent less likely to experience a stroke over a 10-year-period, relative to women who ate fish less than once a week.

"Fish consumption in many countries, including the U.S., is far too low, and increased fish consumption would likely result in substantial benefits in the population," said Dr. Dariush Mozaffarian of the Harvard School of Public Health, who reviewed the findings for Reuters Health.

When choosing fish to eat, it's best to opt for fish that are rich in omega-3 fatty acids, found most abundantly in fatty fish like salmon, mackerel and albacore tuna. "But any fish is better than none," Mozaffarian noted.

Indeed, these fatty acids likely underlie the benefits of fish on stroke risk, study author Dr. Susanna Larsson of the Karolinska Institute in Stockholm told Reuters Health. "These fatty acids may reduce the risk of stroke by reducing blood pressure and blood (fat) concentrations."

This is not the first study to suggest that people who eat more fish have a lower risk of stroke, and experts already recommend a fishy diet to reduce the risk of cardiovascular problems, Mozaffarian added. "This study supports current recommendations."

Earlier this year, for instance, a study showed that middle-aged and older men who eat fish every day are less likely than infrequent fish eaters to develop a suite of risk factors for heart disease, diabetes and stroke.

In the current study, published in the American Journal of Clinical Nutrition, Larsson and her colleagues looked at 34,670 women 49 to 83 years old. All were free of cardiovascular disease and cancer at the beginning of the study, in 1997.

During 10 years of follow-up, 1,680 of the women (4 percent) had a stroke.

Stroke caused by blockage of an artery that supplies blood to the brain -- also known as a "cerebral infarction" or "ischemic stroke" -- was the most common event, representing 78 percent of all strokes in the study. Other types of strokes were due to bleeding in the brain, or unspecified causes.

Women who ate more than three servings of fish per week had a 16 percent lower risk of stroke than women who ate less than one serving a week. "Not a small effect," Mozaffarian said in an e-mail, noting that it was roughly equivalent to the effect of statin drugs on stroke risk. Furthermore, the researchers asked women about their diets only once, using a questionnaire, which might have caused errors that would underestimate the link between a fishy diet and stroke risk, he explained. "So, the true risk reduction may be larger."

Interestingly, women appeared to benefit most from eating lean fish, when other research shows fatty fish is better for health. This finding may stem from the fact that most fatty fish, such as herring and salmon, is eaten salted in Sweden, Larsson explained. "A high intake of salt increases blood pressure and thus may increase the risk of stroke," she said in an e-mail. "So the protective effects of fatty acids in fatty fish may be attenuated because of the salt."

Indeed, when it comes to fish, not all have equal benefits, Mozaffarian noted - for instance, he said, research has not shown any cardiovascular benefits from eating fast food fish burgers or fish sticks.

In addition, women of childbearing age should avoid certain types of fish known to carry relatively high levels of pollutants, such as shark and swordfish, Mozaffarian cautioned. "This is a very, very short list of fish to avoid or minimize -- there are many, many other types of fish to consume," he said. "Women at risk of stroke are generally beyond their child-bearing years, and so for these women, all types of fish can be consumed."

Larsson and her team speculate that certain nutrients in fish, such as fatty acids and vitamin D, might explain its apparent benefits. The Swedish study cannot prove cause and effect for high fish consumption and lowered stroke risk, however. For instance, fish consumption could be a sign of a generally healthier lifestyle or some other mechanism at work.

Last December, Larsson and colleagues published data from the same group of women in the journal Stroke showing that those who eat a lot of red meat may also be putting themselves at increased risk of stroke.

Vitamins C and E linked to metabolic syndrome in low-income Ecuadorians

BOSTON – (January 4, 2011) With life expectancy increasing in Latin America, age-related disease has become a pressing public health concern. Results of an epidemiological study conducted by researchers at the Jean Mayer USDA Human Nutrition Research Center on Aging (USDA HNRCA) at Tufts University and the Corporacion Ecuatoriana de Biotecnologia showed that the metabolic syndrome, a condition that increases a person's risk of developing cardiovascular disease and type 2 diabetes, was prevalent in a low-income urban community in Ecuador and that a poor diet low in micronutrients appeared to contribute.

The study enrolled 225 women and 127 men age 65 and older, living in three low-income neighborhoods on the outskirts of Quito, the capital of Ecuador. The authors examined the relationship between the metabolic syndrome and micronutrients such as folate, zinc and vitamins C, B12 and E. The participants reported their food intake in biweekly interviews and provided blood samples.

Using the International Diabetes Foundation (IDF) definition, the authors determined that 40 % of the population had the metabolic syndrome, with a disproportionate number of women affected: 81 % compared to 19% of the men, which the authors attribute to more of the women being overweight. According to the IDF, the metabolic syndrome is present in centrally obese men and women, as defined by hip and waist measurements, with at least two of the four following metabolic risk factors: raised triglycerides, reduced high-density lipoprotein (HDL) cholesterol, raised blood pressure, and raised fasting plasma glucose (blood sugar).

"In this population of low-income Ecuadorians, we observed a pattern of high carbohydrate, high sodium diets lacking in healthy fats and good sources of protein. Our blood analyses indicates a significant number of participants weren't consuming enough of a range of micronutrients," says senior author Simin Nikbin Meydani, PhD, DVM, director of the USDA HNRCA and the Nutritional Immunology Laboratory at the USDA HNRCA. "After adjusting for age and sex, we observed significant relationships between the metabolic syndrome and two of the micronutrients, vitamins C and E."

"As a group, the participants did not exhibit low blood levels of vitamin E," Meydani continues. "The association suggests that having higher blood levels of vitamin E may protect against the metabolic syndrome." However, low blood levels of vitamin C were seen in 82% of the participants, which the authors suspect was due to limited intake of fresh fruits and vegetables. The bulk of the participants' calories came from white rice, potatoes, sugar and white bread. The authors noted 55% of the women and 33% of the men were overweight.

"With high-calorie foods lacking essential nutrients serving as pillars of the diet, it is possible to be both overweight and malnourished," Meydani says. "Our data suggests that limited consumption of nutrient dense foods such as chicken, vegetables and legumes makes this small population of Ecuadorian elders even more susceptible to the metabolic syndrome."

Additionally, Meydani and colleagues observed a significant relationship between the metabolic syndrome and C-reactive protein (CRP), a marker of low-grade inflammation that has been associated with cardiovascular disease risk. High CRP blood concentrations were seen in almost half of the population.

The results, published online ahead of print in the journal Public Health Nutrition, build on the authors' previous observational study which noted a high prevalence of two metabolic risk factors -elevated waist circumference and low HDL cholesterol levels- in a population of low income, older Ecuadorian adults.

Meydani, who is also a professor at the Friedman School of Nutrition Science and Policy and the Sackler School of Graduate Biomedical Sciences at Tufts, says the results of the present study are a preliminary step toward understanding metabolic disease risk in older adults living in impoverished areas of Latin America. "To our knowledge, there are few studies of the metabolic syndrome in Latin America. Additional research is needed to affirm that there is a relationship between vitamins C and E intake and the metabolic syndrome and CRP and the metabolic syndrome," she says. "This requires interventional studies in larger, more economically diverse populations of older, Latin American men and women."

Meydani and colleagues view nutrition intervention as a potential strategy for curbing metabolic risk in Latin America. "Presently, there are about 59 million Latin American and Caribbean men and women over the age of 60 and the United Nations predicts the population will reach 101 billion by 2025," Meydani says. "Medical resources are minimal in developing countries and those that are in place are usually not directed toward older adults. Nutrition interventions, such as encouraging older adults to consume more nutrient dense foods, for example, locally grown produce, could reduce the strain on the health care system."

7 January 2011

Study shows vitamin D deficiencies may impact onset of autoimmune lung disease

CINCINNATI—A new study shows that vitamin D deficiency could be linked to the development and severity of certain autoimmune lung diseases.

These findings are being reported in the Jan. 4 edition of the journal Chest.

Brent Kinder, MD, UC Health pulmonologist, director of the Interstitial Lung Disease Center at the University of Cincinnati and lead investigator on the study, says vitamin D deficiencies have been found to affect the development of other autoimmune diseases, like lupus and type 1 diabetes.

"We wanted to see if lack of sufficient vitamin D would also be seen in patients who are diagnosed with an autoimmune interstitial lung disease (ILD) and whether it was associated with reduced lung function," he says.

Some ILD patients first discover they have an undifferentiated connective tissue disease, a chronic inflammatory autoimmune disease that affects multiple organ systems but is not developed enough for physicians to easily recognize and categorize.

Autoimmune diseases occur when the body produces abnormal cells that turn on the body and attack major organs and tissues. Connective tissue diseases include lupus, scleroderma, polymyositis, vasculitis, rheumatoid arthritis and Sjogren's syndrome.

"ILD is a group of diseases that mainly affect the tissues of the lungs instead of the airways, like asthma and emphysema do," says Kinder. "It causes scarring of the lungs, is more difficult to diagnosis and treat than other kinds of lung diseases and is often fatal.

"Since vitamin D deficiency has implications for other manifestations of autoimmune illnesses, we wanted to see it had an effect on the lungs of this patient population."

Researchers evaluated 118 patients from the UC ILD Center database—67 with connective tissue disease-related ILD and 51 with other causes of lung fibrosis—for serum 25-hydroxyvitamin D levels, which indicate levels of vitamin D in the body. Then, they evaluated associations between these serum levels and the patients' conditions.

Overall, those with connective tissue disease-related ILD were more likely to have vitamin D deficiency—52 percent versus 20 percent—and insufficiency—79 percent versus 31 percent—than other forms of ILD.

Among this same group of patients, reduced serum 25-hydroxyvitamin D levels were strongly associated with reduced lung function.

"These findings suggest that there is a high prevalence of vitamin D deficiency in patients with ILD, particularly those with connective tissue disease," Kinder says. "Therefore, vitamin D may have a role in the development of connective tissue disease-related ILD and patients' worsening lung function.

"One of the next steps is to see if supplementation will improve lung function for these patients."

He adds that if these findings are confirmed and vitamin D supplementation is shown to be effective in clinical trials, this may also provide a more natural, inexpensive treatment for the illness.

"Vitamin D is known to be a critical dietary factor for bone and skin health," he says. "Now, we're learning that it could potentially be modified as a treatment to improve ILD as opposed to other, more toxic therapies."

4 January 2011

Dairy fat may cut Type 2 diabetes risk: study

A natural fatty acid found in whole-fat dairy products may lower the risk of Type 2 diabetes, U.S. scientists have found.

Studies on populations show that diets rich in dairy foods such as milk, cheese, yogurt and butter are linked to lower risk of Type 2 diabetes. Animal studies also suggest naturally occurring palmitoleic acid helps protect against insulin resistance and diabetes.

The reasons for the effect are unknown. To find out more about the fatty acid and its potential health benefits, researchers at the Harvard School of Public Health analyzed data from more than 3,736 American seniors who have been followed for 20 years as part of a study on risk factors for cardiovascular diseases.

Unlike industrially produced trans fats found in partially hydrogenated vegetable oils, which have been linked to higher risk of heart disease, trans-palmitoleic acid is found mainly in naturally-occurring dairy and meat. Previous studies have not linked this type of trans fat to higher risk of heart disease.

In the study, participants who said they consumed more whole-fat dairy products had higher levels of trans-palmitoleate in their blood three years later, the study's lead investigator, Dariush Mozaffarian, an epidemiology professor at Harvard and his co-authors report in the December issue of the Annals of Internal Medicine.

People with the highest levels of the fatty acid circulating in their blood had about two-thirds the risk of developing Type 2 diabetes than those with the lowest levels, the researchers found.

How exercise grows a healthy heart

Everyone knows that exercise comes with metabolic and cardiovascular benefits, but scientists understand surprisingly little about how physical activity influences the heart itself. Now, a new study in the December 23rd issue of Cell, a Cell Press publication, offers some of the first molecular-level insights.

The studies in mice suggest that exercise turns on a genetic program that leads the heart to grow as heart muscle cells divide. It appears that shift in activity is driven in part by a single transcription factor (a gene that controls other genes). That gene, known as C/EBPb, was known to play important roles in other parts of the body, but this is the first evidence for its influence in the heart.

"We've identified a pathway involved in beneficial cardiac hypertrophy – the good kind of heart growth," said Bruce Spiegelman of Harvard Medical School.

The findings may have clinical implications, particularly for those with heart failure or other conditions that make exercise difficult to impossible, the researchers say.

"This is yet another reason to keep on exercising," said Anthony Rosenzweig of Harvard Medical School. "In the longer term, by understanding the pathways that benefit the heart with exercise, we may be able to exploit those for patients who aren't able to exercise. If there were a way to modulate the same pathway in a beneficial way, it would open up new avenues for treatment."

There may also be ways to optimize training regimens such that they tap into this natural mechanism more efficiently, Spiegelman added.

Researchers had known that heart muscle adapts to increased pressure and volume by increasing in size. That's true in the case of exercise as it is in pathological conditions including high blood pressure. In disease states as opposed to exercise, those changes to the heart can ultimately lead to heart failure and arrhythmias.

In the new study, the researchers sought to better understand those differences using methods developed in the Spiegelman lab that allowed them to quantify changes in the expression of transcription factors in the heart at the genome-wide level in both exercised mice and those who had their aortas surgically constricted, a treatment that leads to a pathological increase in heart size.

The researchers found changes in 175 transcription factors in exercised mice and 96 in mice whose aortas were constricted. Importantly, the changes showed little overlap between the two animal models. For instance, the researchers said, 13 percent of the genes with differential expression following exercise have known or suggested roles in cell proliferation compared to less than one percent of those that changed with the surgery.

The researchers then zeroed in on one transcription factor, C/EBPb, which goes down about two-fold with exercise and a second that rises in turn. Studies in animals and cell culture showed that the decline in C/EPBb leads to changes that appear to be consistent with those that follow endurance exercise, including an increase in heart muscle size and proliferation. Those mice with lower C/EPBb levels also were resistant to heart failure.

That finding is key given that there is little prior evidence showing that the increase in heart size with exercise has direct benefits, the researchers say. The new evidence also gives important biological insights into the heart's potential for regeneration of muscle.

Rosenzweig said it will be important in future studies to explore all of the players in the pathway and to provide even more definitive evidence that exercise leads to an increased rate of cell proliferation in heart muscle.

Highest-Paid U.S. Doctors Get Rich With Fusion Surgery Debunked by Studies

Mikel Hehn poses in St. Cloud, Minnesota, with the daily medications he takes to combat pain and depression as a result of his spinal surgery. Photographer: Andy King/Bloomberg
Suffering from an aching back, truck driver Mikel Hehn went to see surgeon Jeffrey Gerdes in 2008. The St. Cloud, Minnesota, doctor diagnosed spinal disc degeneration, commonly treated with physical therapy, and said surgery wasn’t called for.
Unhappy with the answer, Hehn turned to Ensor Transfeldt, a surgeon at Twin Cities Spine Center in Minneapolis. Transfeldt performed fusion surgery on Hehn, screwing together three vertebrae in his lower spine.

Fusion aims to limit painful spine movements. This one didn’t work out. Two years later, the pain in Hehn’s neck, lower back, buttocks and thighs is so bad that he can’t hold a job and seldom leaves home, he said in an interview.

“There’s days when I just can’t take it and the tears run,” said Hehn, 52, who lives in Sartell, Minnesota. He said he takes oxycodone for pain, Soma to sleep, Lexapro for depression and Imitrex for headaches.
Hehn’s surgery generated a $135,786 bill from Abbott Northwestern Hospital in Minneapolis, feeding a national boom in costly fusion surgeries. It also illustrates how spine surgeons have prospered from performing fusions, which studies have found to be no better for common back pain than physical therapy is -- and a lot more dangerous.

The number of fusions at U.S. hospitals doubled to 413,000 between 2002 and 2008, generating $34 billion in bills, data from the federal Healthcare Cost and Utilization Project show. The number of the surgeries will rise to 453,300 this year, according to Millennium Research Group of Toronto.

Unnecessary Surgeries

The possibility that many of these and other surgeries are needless has gotten little attention in the debate over U.S. health care costs, which rose 6 percent last year to $2.47 trillion. Unnecessary surgeries cost at least $150 billion a year, according to John Birkmeyer, director of the Center for Healthcare Outcomes & Policy at the University of Michigan.

“It’s amazing how much evidence there is that fusions don’t work, yet surgeons do them anyway,” said Sohail Mirza, a spine surgeon who chairs the Department of Orthopaedics at Dartmouth Medical School in Hanover, New Hampshire. “The only one who isn’t benefitting from the equation is the patient.”
The Twin Cities Spine bill for Hehn’s surgery was $19,292, his medical records show. The firm received $8,978 after an insurance discount, $7,742 of it for Transfeldt’s services. Hehn’s insurer paid after his bid for workers’ compensation coverage was denied on grounds he wasn’t injured on the job.

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