Among men with symptoms of heart disease, those who are obese tend to live longer than their normal-weight counterparts, a new study suggests.

Researchers found that among nearly 6,900 male veterans assessed for symptoms of heart disease, those who were obese were less likely to die over the next 7.5 years compared with normal-weight men.

Past research has linked obesity to longer survival among people with heart failure, a chronic condition in which the heart muscle is too weak to pump enough blood to meet the body's needs. Some studies also suggest that obese patients fare better following heart bypass surgery.

Now the new findings, published in The American Journal of Medicine, suggest that this so-called "obesity paradox" extends to other heart disease patients as well.

The study does not, however, mean that obesity is a health boon, stress Dr. Paul McAuley and his colleagues at the VA Palo Alto Health Care System in California. Obesity is linked to a higher risk of developing type 2 diabetes, heart disease and other illnesses.

A lifetime of obesity might have different effects on longevity, they speculate.

It's also not clear that obesity, per se, confers a survival advantage in heart disease. One recent study found that the obesity paradox might be explained by doctors' tendency to treat obese heart disease patients more aggressively.

The current findings are based on a follow-up of 6,876 men who were referred for exercise stress testing due to possible heart disease symptoms. Over an average of 7.5 years, 23 percent of the men died.

After the researchers accounted for patients' fitness levels on the exercise test, as well as heart risk factors, such as high blood pressure and diabetes, they found that obese men were 35 percent less likely to die during the study period than were normal-weight men.

Because the study group consisted of older men with heart disease symptoms, the findings may not be broadly relevant, McAuley and his colleagues point out. It's not known, for example, whether in a group of initially healthy people, obese individuals would tend to live longer.

More studies, the researchers conclude, are needed to fully understand the reasons for the obesity paradox.