Midlife Body Mass Index Predicts Stroke Risk

Increased body mass index (BMI) in midlife is associated with an increased risk of stroke among men, according to a prospective population study over 28 years reported by researchers at Sahlgrenska University Hospital in Goteborg, Sweden.

Since prevention is the best way of reducing the impact of stroke, identifying potential risk factors is very important. To date, however, research has been inconclusive. Some studies have suggested that increased BMI raises the risk of stroke, while others have not.

Katarina Jood, MD, and colleagues investigated the association between BMI and total, ischemic, and hemorrhagic stroke among a random sampling of 7,402 men enrolled in the Multifactor Primary Prevention Study, which began in 1970.

During 28 years of follow-up, 873 of the men sustained a stroke—495 had a first ischemic stroke, 144 had a first hemorrhagic stroke, and in 234 cases the type of stroke was not specified.

Analysis of data revealed that increased BMI was associated with an increased risk for total, ischemic, and unspecified stroke, but not for hemorrhagic stroke. The additive effect of BMI on stroke risk holds up even after considering factors such as diabetes, hypertension, and cholesterol levels. Compared with men with BMI of 20 to 22.49, the most obese men, with BMI over 30, had nearly twice the risk of total and ischemic stroke.