Smoking affects the phenotype of Alzheimer disease.

Because epidemiologic and in vitro evidence conflict, the authors studied the association between smoking and Alzheimer disease (AD) in 46 never, 47 former, and 15 active smokers with AD followed to autopsy. Disease parameters were examined by smoking status and amount smoked in bivariate tests and in multivariate models controlling for age, sex, education, and APOE status. Smoking status was not associated with cognitive or neuropathologic measures. However, active smokers were significantly younger at death and higher levels of smoking were associated with shorter disease duration.