High-risk diabetic patients in Medicare Part D programs: are they getting the recommended ACEI/ARB therapy?

BACKGROUND: Diabetes patients with hypertension and/or renal disease are at an increased risk of cardiovascular morbidity and mortality. Clinical evidence suggests that the use of ACEI/ARB for these patients improves patient outcomes.
OBJECTIVE: To describe ACEI/ARB utilization among high-risk patients with diabetes and to identify patient characteristics that predict suboptimal utilization of ACEI/ARB.
DESIGN: A retrospective cohort study. PATIENTS: Diabetic patients with coexisting hypertension and/or renal disease with continuous Medicare coverage from October 1, 2005 through June 30, 2006 in six states (Alabama, California, Florida, Mississippi, New York, and Ohio). INTERVENTIONS AND MEASUREMENTS: Any ACEI/ARB use during the first 6 months of 2006.
RESULTS: A total of 1,250,466 Medicare Part D enrollees met our inclusion criteria. ACEI/ARB utilization rates were 63%, 58.3%, and 43.1% among diabetic patients with hypertension and renal disease, hypertension without renal disease, and renal involvement without hypertension, respectively. After adjusting for all other characteristics studied, patients in the hypertension only (OR 0.83; 95% CI: 0.82-0.84) and renal disease only (OR: 0.48; 95% CI: 0.46-0.50) risk groups were less likely to use ACEI/ARB compared to diabetes patients with both hypertension and renal disease. Several demographics, including male gender, age older than 65, and white race, were all predictors of suboptimal ACEI/ARB use. Results from state-specific analyses are consistent with those for all six states.
CONCLUSION: In this cohort, less than 60% of high-risk patients with diabetes were receiving the recommended ACEI/ARB therapy. Several patient demographic and clinical characteristics are strongly associated with suboptimal ACEI/ARB use.