Antihypertensive medication use and risk of cognitive impairment: the Honolulu-Asia Aging Study

Abstract

Objective: To determine the associations between classes of antihypertensive medication use and the risk of cognitive impairment among elderly hypertensive men.

Methods: The Honolulu-Asia Aging Study is a prospective, community-based cohort study of Japanese American men conducted in Honolulu, Hawaii. We examined 2,197 participants (mean age 77 years at cohort entry, 1991-1993, followed through September 2010) with hypertension and without dementia or cognitive impairment at baseline, who provided information on medication use. Cognitive function was assessed at 7 standardized examinations using the Cognitive Abilities Screening Instrument (CASI). Cognitive impairment was defined as a CASI score <74.

Results: A total of 854 men developed cognitive impairment (median follow-up, 5.8 years). β-Blocker use as the sole antihypertensive drug at baseline was consistently associated with a lower risk of cognitive impairment (incidence rate ratio [IRR] 0.69; 95% confidence interval [CI] 0.50-0.94), as compared with men not taking any antihypertensive medications, adjusting for multiple potential confounders. The use of diuretics, calcium channel blockers, angiotensin-converting enzyme inhibitors, or vasodilators alone was not significantly associated with cognitive impairment. Results were similar excluding those with cardiovascular disease or <1 year of follow-up, and additionally adjusting for pulse pressure, heart rate, baseline and midlife systolic blood pressure, and midlife antihypertensive treatment (IRR 0.65; 95% CI 0.45-0.94). The association between β-blocker use and cognitive impairment was stronger among men with diabetes, men aged >75 years, and those with pulse pressure ≥70 mm Hg.

Conclusions: β-blocker use is associated with a lower risk of developing cognitive impairment in elderly Japanese American men.

Figure 1. Design of the HHP/HAAS cohorts and derivation of the analytic sample

CASI = Cognitive Abilities Screening Instrument; DBP = diastolic blood pressure; HAAS = Honolulu-Asia Aging Study; HHP = Honolulu Heart Program; SBP = systolic blood pressure.

Figure 2. Sensitivity analyses of the risk of cognitive impairment according to antihypertensive medication use

Reference group: men without antihypertensive medication use. Cognitive impairment defined as Cognitive Abilities Screening Instrument (CASI) score <74. Model adjusts for age, education, APOE ε4 status, childhood years in Japan, baseline CASI score, body mass index, smoking, alcohol consumption, physical activity, diabetes, and cardiovascular disease. BB = β-blocker; CI = confidence interval; IRR = incidence rate ratio; PP = pulse pressure.