OBJECTIVES: To determine whether prescription drug benefits are associated with the use of guideline recommended medications by older persons with type 2 diabetes mellitus (DM).
DESIGN: Cross-sectional study.
PARTICIPANTS: A national sample of Medicare beneficiaries with DM aged 65 and older and an indication for angiotensin-converting enzyme inhibitor (ACEI) or angiotensin II–receptor blocker (ARB) use or high risk of coronary heart disease (hypertension or current smoking) who participated in the 2003 Medicare Current Beneficiary Survey.
MEASUREMENTS: Prescription drug coverage was measured according to self-report and verified according to insurance claims. Outcome variables were use of an ACEI or an ARB (ACEI/ARB) or a statin or use of an ACEI/ARB and a statin. Survey-weighted multinomial logistic regression was used to identify the independent effect of drug coverage on one of two categories of recommended medication use (ACEI/ARB or statin or ACEI/ARB and statin) compared with the reference category of none after controlling for sociodemographic characteristics and health status.
RESULTS: The final study sample was 1,181 (weighted N=4.0 million). Overall, 23% had no drug coverage, 16% Medicaid coverage, 43% employer coverage, 9% Medigap coverage, and 9% Department of Veterans Affairs (VA) or state-sponsored low-income coverage. Overall, 33% received a statin and an ACEI/ARB, 44% only an ACEI/ARB or a statin, and 23% neither. After adjustment, VA and state-sponsored drug benefits were most strongly associated with combined ACEI/ARB and statin use (relative risk ratio (RRR)=4.83, 95% confidence interval (CI)=2.24–10.4)), followed by employer-sponsored coverage (RRR=2.60, 95% CI=1.67–4.03)).
CONCLUSIONS: Prescription drug benefits from VA and state-sponsored drug programs are strongly associated with use of recommended medications by older adults with DM.