Factors Affecting Conformity to Renin-Angiotensin System Inhibitor Usage in Chronic Kidney Disease and Diabetes Mellitus

J Clin Hypertens (Greenwich). 2011;13:473–478.©2011 Wiley Periodicals, Inc. Renin-angiotensin system inhibitor (RASi) agents improve renal and cardiovascular outcomes in patients with diabetes mellitus (DM) and chronic kidney disease (CKD). Studies examining conformity to guidelines have relied on pharmacy claims or filled prescriptions rather than provider-based information. The main outcome of RASi use was examined in 2889 patients with CKD and DM for its association with patient characteristics and specialty clinic visits. RASi use was 77% during the 2-year study period, and declined with worsening CKD stages (79%, 59%, and 48% in stages III, IV, and V, respectively; P<.0001). By multivariate analysis, hypertension (odds ratio [OR], 5.49, 95% confidence interval [CI], 4.16–7.25); older age (OR, 0.85; 95% CI, 0.78–0.93), and higher glomerular filtration rate (OR, 1.42; 95% CI, 1.31–1.53) were associated with RASi use. In a model examining the effect of each specialty, RASi use was greater in patients attending cardiology (OR, 3.52; 95% CI, 2.63–4.71), pharmacy (OR, 3.15; 95% CI, 2.49–3.98), endocrine (OR, 3.39; 95% CI, 2.22–5.16), and renal clinic visits (OR, 2.04; 95% CI, 1.54–2.71). Diagnosis of hypertension increases RASi usage, whereas older age and lower glomerular filtration rate reduce that likelihood. Appropriate specialty referrals improve conformity to guidelines in practice.