This study is as an observational, longitudinal analysis of heart transplant recipients managed at the University of Colorado Hospital Heart Transplant Program beginning January 1, 2000 with continued care for a minimum of three years. Proteinuria was defined as a urine albumin/creatinine ratio ¡Ý 30 mg/g. Data variables, including urine albumin/creatinine ratio and ACE-I/ARB use, were collected at baseline and at years 1, 2, and 3 post-transplant. Comparison between groups involved a t-test for normally distributed variables. A difference-in-differences estimator was used to account for temporal proteinuria trends between 1 and 3 years between groups. Kaplan-Meier analyses were used to compare time to proteinuria.
56 heart transplant recipients met inclusion criteria; 21 (37.5 % ) did not receive an ACE-I/ARB and 35 (62.5 % ) received an ACE-I/ARB. The cumulative 3-year incidence of proteinuria was 15 % . In the unadjusted analysis, the rate of change in development of proteinuria at 1 to 3 years was lower with ACE-I/ARB therapy compared to those not receiving these therapies (5.5 % vs 10 % , p<0.05). In the adjusted analysis, compared to those not receiving angiotensin blockade, ACE-I/ARB therapy was associated with a trend towards a reduction of proteinuria (HR: 0.354, 95 % CI: 0.08-1.56).
RAS blockade appears to reduce the development of proteinuria in heart transplant recipients.