Casas JP et al. (2005) Effects of inhibitors of the renin–angiotensin system and other antihypertensive drugs on renal outcomes: systematic review and meta-analysis. Lancet 366: 2026–2033

In addition to their capacity to lower systemic blood pressure, angiotensin-converting-enzyme (ACE) inhibitors and angiotensin-II receptor blockers (ARBs) are thought to have specific renoprotective effects in patients with diabetic and nondiabetic nephropathy. Some guidelines advocating the use of these drugs in renal disease, however, base their recommendations on the results of placebo-controlled trials with no clinically relevant endpoints.

Casas et al. have therefore investigated the effects of ACE inhibitors and ARBs on the progression of renal disease, by undertaking a meta-analysis of 127 randomized, controlled trials that used either placebos or other antihypertensive drugs as comparators. Patient outcomes were compared using the primary endpoints of a doubling of the baseline serum creatinine concentration and occurrence of end-stage renal disease. Albuminuria levels, serum creatinine levels and glomerular filtration rates were also analyzed as secondary markers of kidney function.

When ACE inhibitors and ARBs were compared with other antihypertensive drugs, they were shown to slightly reduce the incidence of end-stage renal disease in patients with nondiabetic nephropathy, but this beneficial effect was less evident in large studies with ≥500 participants. In patients with diabetic nephropathy, however, ACE inhibitors and ARBs did not slow the progression of renal disease more effectively than other antihypertensive drugs. As it is still not clear whether there are any specific beneficial effects of ACE inhibitors and ARBs on renal function, the authors note that there is little evidence to support their use for renoprotection.