Angiotensin converting enzyme inhibitors and angiotensin II receptor antagonists for preventing the progression of diabetic kidney disease

Kidney disease develops in 25% to 40% of diabetic patients, usually 20 to 25 years after the onset of diabetes. Approximately one third of those with diabetic kidney disease (DKD) will progress to end-stage kidney disease (ESKD) and will require long-term dialysis or possibly receive a kidney transplant. Many patients however may die from associated coronary artery disease or other cardiovascular causes before the onset of ESKD. Antihypertensive drugs have been shown to not only be of benefit to the heart but to also provide kidney protection by slowing the progression of DKD to ESKD. Two drugs in particular have been considered equally effective for patients with DKD - these are angiotensin converting enzyme inhibitors (ACEi) and angiotensin II receptor antagonists (AIIRA). However studies have focused on kidney protection rather than over mortality. The aim of this review was to assess the benefits and harms or ACEI and AIIRA therapy in patients with DKD. Fifty studies (13,215 patients) were identified comparing ACEi to placebo, AIIRA to placebo and ACEi to AIIRA. The risk of death from any cause was not significantly reduced with the use of ACEi versus placebo, AIIRA versus placebo or ACEi versus AIIRA. However when we looked at the studies which used the maximum dose tolerated of ACEi rather than the lower, so-called renal doses, there was a significant reduction in the risk of death due to any cause. We were unable to determine which drug provides better protection due to the lack of head-to-head trials.