Bug in the gut may trigger obesity

ST. LOUIS, -- Very efficient bacteria in the digestive tracts of obese people may provide a theory on why they get fat, U.S. researchers said. Humans need the bacteria to help convert indigestible foods into a digestible form and bacteria in obese people are better at the conversion, scientists from Washington University in St. Louis said in two papers published in Nature. Because the bacteria are good at their job, obese people get more energy than non-obese people from the same amount of food -- and those extra calories are deposited in fat. In both studies, a family of bacteria known as firmicutes was more plentiful in obese patients, scientists said. They concluded the firmicutes were better at digesting food, such as complex sugars, that the body can't. When obese people lost weight, the amount of firmicutes fell. One paper studied humans, the other mice. If the findings hold true under further study, researchers said methods could be developed to induce weight loss or prevent weight gain. Others said it was too soon to manipulate the bacteria in hopes of a slimmer body. For example, the amount of efficient bacteria could be a result of obesity, not its cause.

Women less likely to get heart device

DALLAS, -- Mayo Clinic researchers in Rochester, Minn., say women with heart failure are less likely than men to receive cardiac resynchronization therapy. Cardiac resynchronization therapy has been shown to enhance quality of life for people with heart failure; and women who receive CRT live longer than men who are given the therapy, according to research presented Tuesday during the American Heart Association's annual Scientific Sessions in Dallas. The cases of 373 patients who underwent implantation of a CRT device at Mayo Clinic between 1999 and 2004 were reviewed to determine gender-specific referrals and evaluate how the patients -- 82 percent male -- fared with the therapy. Survival at five years for women -- 76 percent -- was much higher than that of the men, at 46 percent. "Our data highlight a potentially important gender bias, in that fewer women ... are being referred for cardiac resynchronization therapy compared with a similar group of males," said Dr. Grace Lin, lead author of the study. "It is another example in recent years of potential under-treatment of women with heart disease in this country. Whether such 'referral bias' is universal, however, deserves further study."

Heart failure patients at risk for stroke

DALLAS, -- Mayo Clinic researchers say they've determined people with heart failure face are twice as likely to die from a stroke as the general population. Researchers studied 630 patients with heart failure from 1979 through 1999. They found that during the 30 days following a heart failure diagnosis, patients were at a 17-fold increased risk of stroke as compared with the general population, and the risk remained elevated during the five years of follow-up. "This research shows that preventing strokes has the potential to improve survival among patients with heart failure, and that stroke prevention should be among our key priorities for patients newly diagnosed with heart failure," said Dr. Veronique Roger, who led the study. The occurrence of a stroke among heart failure patients resulted in a large increase in the risk of subsequent death compared with heart failure patients who remained stroke free. Older people with a previous stroke or diabetes were more likely to experience a stroke, the research found. Nearly 5 million Americans are living with heart failure, and 550,000 new cases are diagnosed annually. The study was presented Tuesday, during the American Heart Association's annual Scientific Sessions meeting in Dallas.