APOE genotype, plasma lipids, lipoproteins, and AD in community elderly.

BACKGROUND: Genetic variation at the APOE locus has a major influence on both plasma lipid levels and the risk of AD. The relationship between APOE genotype and plasma lipids may influence the risk of AD. OBJECTIVE: In a community-based study of white, African American, and Caribbean Hispanic elderly in New York City, we investigated the relationship between plasma lipids and AD as well as the possible influence of APOE genotype on this relationship. METHODS: Total plasma cholesterol (TC), low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and triglyceride levels were investigated in a cross-sectional study of nondemented elderly and patients with AD and in a prospective study of incident AD. Analyses included APOE genotype, gender, ethnicity, body mass index, and other potential confounders such as a history of hypertension, smoking, aspirin use, previous stroke, or ischemic heart disease. RESULTS: Compared with nondemented elderly, decreased TC level had a weak but significant inverse association with incident AD, independent of APOE genotype. No other lipoprotein fragment was associated with either prevalent or incident AD. CONCLUSION: Our results suggest that no consistent relationship exists between APOE genotype, plasma lipoproteins, and AD.