Is combining ACE inhibitors and ARBs helpful or harmful?

The combination of angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) has been studied for treatment of heart failure, hypertension, and proteinuric renal disease. Combination therapy with an ACE inhibitor and an ARB decreases symptoms in heart failure patients, but does not appear to have an impact on overall mortality (strength of recommendation [SOR]: A). Preliminary data from small trials indicate that combination therapy may be more effective than monotherapy with an ACE inhibitor or an ARB for lowering blood pressure (SOR: B), although morbidity and mortality data for the combination are not currently available. Additionally, in trials involving diabetic and nondiabetic proteinuric renal disease, the combination of ACE inhibitors and ARBs delays progression of renal disease to a greater extent than monotherapy; however, mortality data are also unavailable (SOR: A)