Abstract 10588: Medicare Part D Medication Use in a Community Cohort With Hypertension: The Atherosclerosis Risk in Communities (ARIC) Study
Context: Despite proven benefits for reducing incidence of major cardiac events, antihypertensive drug therapy remains underutilized in the United States.
Objectives: To identify antihypertensive drug therapy use, utilization predictors, and associations between use and outcomes/resource use.
Design/Methods: This study included ARIC cohort participants reporting hypertension history without prevalent cardiovascular disease (MI, CVA, PCI, CABG, or HF admission history) during 2006-2007 annual follow-up calls, using ARIC records linked to 2006-2009 Medicare claims. Antihypertensive utilization was measured as 80%+ proportion days covered (PDC) using Medicare Part D claims, a commonly used adherence measure, for at least one antihypertensive class in the three months preceding annual follow-up. Poisson regression was used to evaluate adjusted associations between patient characteristics and medication use. Inverse probability weighting was used to adjust associations between antihypertensive use and outcomes/resource use.
Results: Among 1,849 hypertensive participants with Part D coverage, 31.6% had no antihypertensive class with 80%+ PDC in the three months preceding annual follow-up. Common classes, among those receiving 1+ class, were ACE inhibitors/ARBs (56.4%), thiazides (48.1%), beta blockers (34.6%), and calcium channel blockers (31.0%). Mean age was 72.8 years; 70.8% were female, and 28.1% African-American. After adjustment for confounders, positive predictors of use included female gender and diabetes; negative predictors were African-American race and current smoking. Adjusted associations between receiving no therapy and a composite endpoint of CV death, MI, CVA, PCI, CABG, and HF admission was not statistically significant (HR: 1.32; 95% CI: 0.93, 1.86) nor was the adjusted association with Medicare Part A payments (incremental difference at 36 months: $481; 95% CI: -$2804, $3765).
Conclusions: Despite having medical and prescription coverage, nearly a third of hypertensive participants received no antihypertensive drug therapy at 80%+ PDC. While not statistically significant, the difference in clinical outcomes associated with not receiving therapy was consistent with results from randomized trials.
- © 2013 by American Heart Association, Inc.