Association of incident Alzheimer disease and blood pressure measured from 13 years before to 2 years after diagnosis in a large community study

Background: It is uncertain whether high blood pressure increases the risk of developing Alzheimer disease (AD). Objective: To examine the association between incident AD and blood pressure measured up to 13 years before diagnosis. Design: Longitudinal cohort study conducted from 1982 to 1988, with blood pressure measured every 3 years in home interviews, and in 1973 for a portion (60%) of the sample. Setting: Community of East Boston, Mass. Participants: Six hundred thirty-four subjects 65 years or older and without AD were selected as a stratified random sample of participants of the East Boston Established Populations for Epidemiologic Studies of the Elderly. Main Outcome Measure: Alzheimer disease was diagnosed by a neurologist using a structured clinical evaluation. Results: High blood pressure was not associated with an increased risk of AD in logistic regression models adjusted for age, sex, and level of education. There was no association with systolic pressure measured 13 years before diagnosis (odds ratio = 1.03/10 mm Hg; 95% confidence interval, 0.80-1.32) and an inverse association with systolic pressure measured 4 years before diagnosis (odds ratio = 0.82/10 mm Hg; 95% confidence interval, 0.72-0.95). Associations for diastolic pressure were in the same direction as those for systolic pressure except with wider confidence intervals. The odds ratios were not materially different with further adjustment for cardiovascular risk factors and diseases. Conclusion: In this large community study, high C, blood pressure was not associated with an increased risk of AD.