It has been hard to determine how obesity and overweight affect risk in AD because weight loss frequently occurs before clinical symptoms of dementia appear, according to first author of the study, Deborah Gustafson, Ph.D., who conducted research for the study while at Gothenburg University in Gothenburg, Sweden.
"Overweight and obesity are very closely associated with vascular diseases, such as diabetes, coronary heart disease and hypertension. And there is more and more evidence that vascular diseases are very important as risk factors in AD," said Gustafson. "But because of the weight loss associated with pre-clinical dementia, it takes an extended study to uncover the dangers that overweight may pose to a very elderly population."
Women in the study who developed AD between the ages of 79 and 88 were significantly more likely to have been overweight at age 70, as well as at 75 and 79. The women who developed AD were much heavier, with a body mass index (BMI) an average of 3.6 units higher than that of women who did not become demented. For every unit increase in BMI at age 70, the risk of developing AD increased by 36 percent.
BMI is a measure of body fatness in both men and women based on height and weight. BMI is calculated as kilograms per meter squared. A BMI between 18.5 and 24.9 is considered normal weight. A BMI over 25 is defined as overweight and 30 or greater as obese. Women who had a BMI greater than 29 when they were 70 years old were more likely to have AD in their 80s. A BM
Contact: Jeanne Galatzer-Levy