Predicting Alzheimer's disease in the Baltimore longitudinal study of aging.

Longitudinal studies offer opportunities for studying children whose parents have Alzheimer's disease. The Baltimore Longitudinal Study of Aging (BLSA) has examined adult cognitive performance but has not systematically recruited participants' children. We initiated studies of dementia in the 1980s. This work suggested that hormone replacement and use of nonsteroidal anti-inflammatory drugs reduced the risk of Alzheimer's disease and that risk for Alzheimer's disease could be predicted from cognitive performance as many as 20 years prior to its onset. More recently, we showed that premorbid levels of free testosterone were lower in men who developed Alzheimer's disease and premorbid depressive symptomatology was a risk for Alzheimer's disease in men but not women as many as 6 years before the onset of dementia. Participants in the BLSA include family members with a variety of degrees of relationship, but there is no systematic effort to collect data from relatives of participants.