Drug benefit generosity and essential medication use among Medicare-eligible retirees

Objective: To examine the association between generosity of drug coverage and essential cardiovascular medication use among retired seniors. Study Design: Retrospective analysis of the 1997 to 2000 Medicare Current Beneficiary Survey, a nationally representative survey of the Medicare population. Methods: The study examined community-dwelling fee-for-service Medicare beneficiaries aged 65 years or older with retiree health insurance and with coronary heart disease and hyperlipidemia (n = 1220) or congestive heart failure (n = 1147). Generosity of drug coverage was defined as the percentage of the beneficiary's annual drug expenditures paid by the employer. Dependent variables were any statin use for the group with coronary heart disease and hyperlipidemia and any angiotensin-converting enzyme inhibitor or angiotensin receptor blocker use in the group with congestive heart failure. Logistic regression analyses estimated the adjusted odds of essential medication use by generosity category in each disease group. We estimated the extent to which medication use would change if generosity levels moved to those under standard Medicare Part D levels. Results: The overall prevalence of statin use was 64.1%, and that of angiotensin-converting enzyme inhibitor or angiotensin receptor blocker use was 50.0%. In both disease groups, retirees in the less generous drug coverage categories had significantly lower adjusted odds of use than retirees with the most generous drug benefits (ie, covering ≥76% of annual drug expenditures). Overall, the shift to a standard Medicare Part D structure would result in mean declines of 8.4% in statin use and 5.2% in angiotensin-converting enzyme inhibitor or angiotensin receptor blocker use. Retirees with the most generous drug coverage face twice the mean decline in drug use. Conclusion: Retirees who already have generous drug benefits from their employers may be placed at risk for decreased utilization of effective medications due to any future scaling back of retiree drug coverage.