Renoprotective Effect of Renin-Angiotensin-Aldosterone System Blockade in Patients With Predialysis Advanced Chronic Kidney Disease, Hypertension, and Anemia

Abstract

IMPORTANCE: The benefit of using a renin-angiotensin-aldosterone system blocker such as an angiotensin-converting enzyme inhibitor (ACEI) or an angiotensin II receptor blocker (ARB) for patients with advanced chronic kidney disease (CKD) remains undetermined. OBJECTIVE: To assess the effectiveness and safety of ACEI/ARB use for advanced predialysis CKD in patients with hypertension and anemia. DESIGN Prospective cohort study. SETTING: Taiwan. PARTICIPANTS: From January 1, 2000, through June 30, 2009, we selected 28 497 hypertensive adult patients with CKD. Serum creatinine levels were greater than 6 mg/dL, hematocrit levels were less than 28%, and patients were treated with erythropoiesis-stimulating agents. INTERVENTIONS: Users (n = 14,117) and nonusers (n = 14,380) of ACEIs/ARBs. MAIN OUTCOMES AND MEASURES: We used Cox proportional hazards regression models to estimate hazard ratios (HRs) for commencement of long-term dialysis and all-cause mortality for ACRI/ARB users vs nonusers. RESULTS: In a median follow-up of 7 months, 20,152 patients (70.7%) required long-term dialysis and 5696 (20.0%) died before progression to end-stage renal disease requiring dialysis. Use of ACEIs/ARBs was associated with a lower risk for long-term dialysis (HR, 0.94 [95% CI, 0.91-0.97]) and the composite outcome of long-term dialysis or death (0.94 [0.92-0.97]). The renal benefit of ACEI/ARB use was consistent across most patient subgroups, as was that of ACEI or ARB monotherapy. Compared with nonusers, the ACEI/ARB users had a higher hyperkalemia-associated hospitalization rate, but the risk of predialysis mortality caused by hyperkalemia was not significantly increased (HR, 1.03 [95% CI, 0.92-1.16]; P = .30). CONCLUSIONS AND RELEVANCE: Patients with stable hypertension and advanced CKD who receive therapy with ACEIs/ARBs exhibit an association with lower risk for long-term dialysis or death by 6%. This benefit does not increase the risk of all-cause mortality.