An economic evaluation of Losartan therapy in type 2 diabetic patients with nephropathy: an analysis of the RENAAL study adapted to France

The RENAAL study enrolled 1,513 patients with type 2 diabetes mellitus and nephropathy defined by the presence of proteinuria (urinary albumin: creatinine ratio 300 mg/g or proteinuria > 500 mg per day). Compared to placebo, losartan therapy reduced by 16% (p=0.02) the risk of a composite endpoint (doubling of baseline serum creatinine level, end stage renal disease, or death) and by 28% (p=0.002) the risk of progression to end stage renal disease (ESRD).

The objective of this study was to compare, using French economic data, the additional cost of losartan therapy with the savings in cost generated by a decrease in the number of end stage renal disease days. Prospectively collected health care resource utilization were used (N(losartan)=751, N(placebo)=762). The follow-up period was 4 years.

The mean cumulative cost of losartan over 4 years was 1,603 euros per patient. The reduction in the number of ESRD days over 4 years in patients treated with losartan significantly decreased costs associated with ESRD by 7,438 euros per patient (CI 95%: 3,029 euros - 11,847 euros, p=0.001). Compared to the placebo group, the average cost per patient over 4 years in the losartan group was lower by 5,834 euros (CI 95%: 1,407 euros - 10,301 euros, p=0.01).

In addition to the medical benefit, this analysis demonstrated the economic relevance of treatment with losartan in type 2 diabetic patients with nephropathy.