Use of losartan in diabetic patients in the primary care setting: review of the results in LIFE and RENAAL.

Objective: To review outcomes of diabetic patients treated with losartan in two recent randomized, double-blind, clinical trials and compare outcomes to similar studies in diabetics.

Methods: The Reduction in ENdpoints with the Angiotensin II Antagonist Losartan (RENAAL) study recruited 1513 patients with type 2 diabetes and nephropathy. The Losartan Intervention For Endpoint reduction (LIFE) study recruited 9193 hypertensive patients with left ventricular hypertrophy (LVH) including 1195 with diabetes mellitus. The maximum losartan dose in both studies was 100 mg daily. All study patients could receive additional antihypertensive medications, excluding angiotensin converting enzyme inhibitors (ACEIs) and other angiotensin receptor blockers (ARBs), if blood pressures (BP) < 140/90 mmHg were not achieved. In RENAAL, the control group received placebo whereas in LIFE, controls received atenolol. BP reductions were comparable in the treatment and control groups of both studies. In RENAAL, the primary outcome was the composite of doubling of serum creatinine, end-stage renal disease, or death. In LIFE, the primary composite outcome was cardiovascular death and non-fatal myocardial infarction or stroke.

Results: In RENAAL, losartan reduced the primary composite end-point 16% (p = 0.02) and the incidence of end-stage renal disease (ESRD) 28% (p = 0.002). In LIFE, the primary composite endpoint among diabetics was reduced 24% (p = 0.03), cardiovascular mortality was reduced 37% (p = 0.03) and total mortality was reduced 39% (p = 0.002).

Discussion: In diabetic patients with nephropathy, losartan reduces progression to endstage renal disease. In hypertensive diabetic patients with LVH, losartan reduces cardiovascular morbidity and mortality and total mortality. Angiotensin receptor blockade with losartan appears to confer benefits beyond BP reduction in diabetic patients at high-risk for cardiovascular and renal events.