Report finds obesity may be health threat

CHICAGO – Middle-age people who are overweight but have normal blood pressure and cholesterol levels are kidding themselves if they think their health is just fine.

Northwestern University researchers tracked 17,643 patients for three decades and found that being overweight in mid-life substantially increased the risk of dying of heart disease later in life – even in people who began the study with healthy blood pressure and cholesterol levels.

High blood pressure and cholesterol are strong risk factors for heart disease. Both are common in people who are too fat, and often are thought to explain why overweight people are more prone to heart disease.

But there is a growing body of science suggesting that excess weight alone is an independent risk factor for heart attacks, strokes and diabetes.

The new study fits with that evolving school of thought and contrasts with a controversial government study published last year that suggested excess weight might not be as deadly as previously thought.

“The take-home message would be pay more attention to your weight even if you don’t have an unhealthy risk factor profile yet,” said lead author Lijing Yan, a researcher at Northwestern and Peking University.

The study appears in today’s Journal of the American Medical Association.

Participants were Chicago-area men and women in their mid-40s on average who had no heart disease or diabetes when the study began. They were followed for an average of 32 years. The researchers tracked deaths from cardiovascular disease and diabetes, and hospitalizations for those conditions, starting at age 65.

A total of 1,594 heart disease deaths occurred, 31 of them in people who started the study with normal blood pressure and cholesterol.

Among participants with normal blood pressure and cholesterol at the start, those who were obese – or grossly overweight – were 43 percent more likely than normal-weight participants to die of heart disease later on. They were also four times as likely to be hospitalized for heart disease.

Participants who were modestly overweight but had normal blood pressure and cholesterol still ran a higher risk than the normal-weight people.

The study “will help define obesity as a disease” in itself, said Dr. Samuel Klein, an obesity expert at Washington University in St. Louis.