ACE Inhibitor, Angiotensin II Receptor Antagonist, Monotherapy or Combined Therapy?

The renin-angiotensin system (RAS) is activated in several diseases, and angiotensin II mediates a number of putative detrimental effects through activation of the angiotensin II type 1 receptor, while the clinical role of the type 2 receptor has not yet been settled. Inhibition of the RAS is either achieved by the use of angiotensin-converting enzyme (ACE) inhibitors or angiotensin II receptor antagonists (AIIA). Although a combined inhibitory therapy might seem attractive, thus far limited data has emerged to support such a strategy. In hypertension, losartan has proven slightly more efficient than atenolol to prevent cardiovascular complications, overall mortality was however identical. In heart failure, AIIA should only be considered in ACE inhibitor-intolerant patients. Both ACE inhibitors and AIIA have proven efficient in diabetic microalbuminuria and in proteinuria. ACE inhibitors are first-line treatment in type 1 diabetic nephropathy and in nondiabetic nephropathy, while AIIA are highly efficient in type 2 diabetic nephropathy. Combination therapy might be superior to monotherapy in nondiabetic nephropathy.