SAN DIEGO – The increased risk of Alzheimer's disease may be more closely related to midlife distribution of adiposity rather than to being overweight or obese, according to the results of a large-scale study presented at the annual meeting of the American Academy of Neurology.
Researchers were able to use data from almost 9,000 members of the Kaiser Permanente Health Plan who underwent a series of tests between 1964 and 1973 when they were aged 40–45 years. One evaluation included measurement of skinfold thickness using calipers in the subscapular and triceps regions. Between 1994 and 2003, investigators checked medical records for diagnoses of Alzheimer's disease.
The findings showed that people in the upper 20% of adiposity in the subscapular region were almost four times more likely to develop Alzheimer's disease than were those in the lowest 20%. The risk for developing Alzheimer's disease for individuals in the upper 20% of adiposity on triceps measurements was about three and a half times greater than that of people in the lowest quintile, according to lead researcher Dr. Rachel A. Whitmer, a research scientist at the Kaiser Permanente division of research, in Oakland, Calif.
Previous research by Dr. Whitmer (BMJ 2005;330:1360) and others (Arch. Intern. Med. 2003;163:1524–8) has shown that overweight and obesity in middle age increase the future risk of dementia and Alzheimer's disease. However, these studies relied on measurement of body mass index. The data from the current study, in which calipers were used to measure skinfold, were adjusted for body mass index.