SOLVENT EXPOSURE AS A RISK FACTOR FOR ALZHEIMERS-DISEASE - A CASE-CONTROL STUDY

This case-control study investigates whether history of organic solven t exposure is associated with increased risk of Alzheimer's disease, T he study base includes about 23,000 persons aged 60 years or more from the local membership of a health maintenance organization in Seattle, Washington, who entered the study between 1987 and 1992, Probable Alz heimer's disease cases (n = 193) who had presented with new dementia s ymptoms were identified, enrolled, and diagnosed by our Alzheimer's Di sease Patient Registry following standardized criteria, Control subjec ts (n = 243), free of dementia and neurologic disease causing dementia , were selected randomly from the study base and frequency matched to cases for age and sex, Proxy informants provided specific solvent expo sure history as well as job descriptions likely to involve solvent use as part of a comprehensive risk factor interview. Kappa statistics in dicated substantial agreement for control-control proxy solvent respon ses, History of exposure to one or more solvent groups (benzene and to luene; phenols and alcohols; ketones; other solvents) yielded an adjus ted Alzheimer's disease odds ratio of 2.3 (95 percent confidence inter val 1.1-4.7); among males only, it increased to 6.0 (95% confidence in terval 2.1-17.2), Thus, past exposure to organic solvents may be assoc iated with onset of Alzheimer's disease.