A link between body mass index (BMI) - a measure of weight in relation to height - and a hospital or death certificate diagnosis of dementia has been identified in a Swedish study.

Drawing on data collected in the Primary Prevention Study that began in Goteburg in 1970, researchers analyzed 7402 men who were between 47 and 55 years old between 1970 and 1973. None of the men had a history of stroke or heart attack at the start of the study.

Dr. Annika Rosengren of Sahlgrenska University Hospital in Goteburg and a multicenter team classified the subjects into four groups: 22 men diagnosed with Alzheimer’s disease; 78 men with a secondary diagnosis of dementia; 154 diagnosed with dementia as a primary diagnosis or cause of death; and 7148 men who had never been diagnosed with dementia.

According to the team’s report in the Archives of Internal Medicine, they found that the likelihood of dementia rose linearly as body mass index increased.

That is, after factoring in smoking, blood pressure, cholesterol, diabetes, and social strata, men with a BMI of about 20 at the start of the study had the lowest risk of developing dementia, and the risk rose steadily up to 2.5-times greater for men with a BMI of 30 or higher.

“Overweight and obesity,” Rosengren’s group says, “could be major preventable factors in the development of dementia.”

SOURCE: Archives of Internal Medicine, February 14, 2005.