Anti-hypertensive medications and cardiovascular events in older adults with multiple chronic conditions

Abstract

Importance: Randomized trials of anti-hypertensive treatment demonstrating reduced risk of cardiovascular events in older adults included participants with less comorbidity than clinical populations. Whether these results generalize to all older adults, most of whom have multiple chronic conditions, is uncertain. Objective: To determine the association between anti-hypertensive medications and CV events and mortality in a nationally representative population of older adults. Design: Competing risk analysis with propensity score adjustment and matching in the Medicare Current Beneficiary Survey cohort over three-year follow-up through 2010. Participants and Setting: 4,961 community-living participants with hypertension. Exposure: Anti-hypertensive medication intensity, based on standardized daily dose for each anti-hypertensive medication class participants used. Main Outcomes and Measures: Cardiovascular events (myocardial infarction, unstable angina, cardiac revascularization, stroke, and hospitalizations for heart failure) and mortality. Results: Of 4,961 participants, 14.1% received no anti-hypertensives; 54.6% received moderate, and 31.3% received high, anti-hypertensive intensity. During follow-up, 1,247 participants (25.1%) experienced cardiovascular events; 837 participants (16.9%) died. Of deaths, 430 (51.4%) occurred in participants who experienced cardiovascular events during follow-up. In the propensity score adjusted cohort, after adjusting for propensity score and other covariates, neither moderate (adjusted hazard ratio, 1.08 [95% CI, 0.89-1.32]) nor high (1.16 [0.94-1.43]) anti-hypertensive intensity was associated with experiencing cardiovascular events. The hazard ratio for death among all participants was 0.79 [0.65-0.97] in the moderate, and 0.72 [0.58-0.91] in the high intensity groups compared with those receiving no anti-hypertensives. Among participants who experienced cardiovascular events, the hazard ratio for death was 0.65 [0.48-0.87] and 0.58 [0.42-0.80] in the moderate and high intensity groups, respectively. Results were similar in the propensity score-matched subcohort. Conclusions and Relevance: In this nationally representative cohort of older adults, anti-hypertensive treatment was associated with reduced mortality but not cardiovascular events. Whether RCT results generalize to older adults with multiple chronic conditions remains uncertain. © 2014 Tinetti et al.