To determine which conditions may be associated with reduced survival in patients with Alzheimer's disease, we studied all death certificates in the United States for 1978 on which senile and presenile dementia (ICDA 290, N = 7,195) was mentioned. Each case was compared with two control deaths. Differences in the frequency of listing on the death certificates for the following conditions reached statistical significance: infections, trauma, nutritional deficiency, chronic ulcer of skin, foreign body in pharynx, cataract, glaucoma, blindness, deafness, Parkinson's disease, and epilepsy. There seem to be many preventable and treatable disorders in patients with senile and presenile dementia.