Being overweight after age 40 could double a man's stroke risk, a new study shows.

It's more evidence that obesity (search) is a major — but modifiable — risk factor for numerous chronic health problems including heart disease, diabetes, cancer, and now stroke risk.

Little research has investigated the stroke-obesity link, and most has produced conflicting results, writes lead researcher Katarina Jood, MD, with the Institute of Clinical Neuroscience at Sahlgrenska University Hospital in Goteborg, Sweden.

Her study appears in the November issue of Stroke: Journal of the American Heart Association.

It shows that treating high blood pressure and diabetes is not enough to prevent stroke, she says in a news release. "Obesity should also be considered a significant risk factor."

Obesity and Stroke Risk

In Jood's study, she and her colleagues examined whether there's an association between high body mass index (search) (BMI, a measure of body fat) and stroke risk. They also looked at whether this association was mediated by the effects of obesity on high blood pressure and diabetes — known stroke risk factors.

The study was conducted in Sweden and involved 7,402 middle-aged men (47-55) whose health was tracked for more than 28 years. There were 873 strokes.

Obese men with a BMI over 30 had doublethe risk of stroke compared with men of normal weight whose BMI was between 20 and 23. Even after other risk factors — like high blood pressure, diabetes, high cholesterol, stress, exercise, smoking, and family history — were factored in, the increased stroke risk still held true, reports Jood.

By Jeanie Lerche Davis, reviewed by Brunilda Nazario, MD

SOURCES: Jood, K. Stroke; November 2004. News release, American Heart Association.