Relation of blood pressure to risk of incident Alzheimer's disease and change in global cognitive function in older persons

Purpose: To examine the relation of systolic and diastolic blood pressure to incident Alzheimer's disease (AD) and rate of cognitive change. Methods: Longitudinal cohort study with annual clinical evaluations. At baseline, blood pressure was measured, apolipoprotein E (APOE) genotyping was performed, and medications were reviewed. Results: 824 older Catholic clergy members without baseline dementia were recruited from across the United States. During a mean of about 6 years of observation, 151 persons developed AD. In a proportional hazards model adjusted for age, sex and education, neither systolic (relative risk = 0.995; 95% CI: 0.986, 1.004, p = 0.249) nor diastolic (relative risk = 1.000; 95% CI: 0.985, 1.015, p = 0.975) blood pressure was related to AD incidence. In mixed effects models, neither systolic nor diastolic blood pressure was related to level or to annual rate of change on a global measure of cognition. These results did not change in subsequent models that accounted for the use of medications with antihypertensive properties or for the possession of an APOE epsilon 4 allele. Conclusions: In a cohort of older persons with a majority taking medications with antihypertensive properties, we did not find a relationship between blood pressure and risk of AD or cognitive decline. Copyright (C) 2006 S. Karger AG, Basel.