Use of angiotensin-converting enzyme inhibitors and angiotensin receptor blockers in high-risk clinical and ethnic groups with diabetes

Abstract

BACKGROUND: Diabetes causes 45% of incident end-stage renal disease (ESRD). Risk of progression is higher in those with clinical risk factors (albuminuria and hypertension), and in ethnic minorities (including blacks, Asians, and Latinos). Angiotensin-converting enzyme inhibitors (ACE) and angiotensin receptor blockers (ARB) slow the progression of diabetic nephropathy, yet little is known about their use among patients at high risk for progression to ESRD. OBJECTIVES: To examine the prevalence of ACE or ARB (ACE/ARB) use overall and within patients with high-risk clinical indications, and to assess for ethnic disparities in ACE/ARB use. DESIGN: Observational cohort study. SETTING: Kaiser Permanente Northern California (KPNC) Diabetes Registry, a longitudinal registry that monitors quality and outcomes of care for all KPNC patients with diabetes. PATIENTS: Individuals (N= 38887) with diabetes who were continuously enrolled with pharmacy benefits during the year 2000, and had self-reported ethnicity data on survey. INTERVENTIONS AND MEASUREMENTS: Pharmacy dispensing of ACE/ARB. RESULTS: Forty-one percent of the cohort had both hypertension and albuminuria, 30% had hypertension alone, and 12% had albuminuria alone. Fourteen percent were black, 11% Latino, 13% Asian, and 63% non-Latino white. Overall, 61% of the cohort received an ACE/ARB. ACE/ARB was dispensed to 74% of patients with both hypertension and albuminuria, 64% of those with hypertension alone, and 54% of those with albuminuria alone. ACE/ARB was dispensed to 61% of whites, 63% of blacks, 59% of Latinos, and 60% of Asians. Among those with albuminuria alone, blacks were significantly (P =.0002) less likely than whites to receive ACE/ARB (47% vs 56%, respectively). No other ethnic disparities were found. CONCLUSIONS: In this cohort, the majority of eligible patients received indicated ACE/ARB therapy in 2000. However, up to 45% to 55% of high-risk clinical groups (most notably individuals with isolated albuminuria) were not receiving indicated therapy. Additional targeted efforts to increase use of ACE/ARB could improve quality of care and reduce ESRD incidence, both overall and in high-risk ethnic groups. Policymakers might consider use of ACE/ARB for inclusion in diabetes performance measurement sets.