[Cost-efectiveness of Ibersartan in type II diabetic nephropathy with hypertension. A Spanish perspective].

BACKGROUND

In the Irbesartan Diabetic Nephropathy Trial (IDNT), treatment with irbesartan demonstrated 23% and 20% reductions in the combined endpoint of doubling of serum creatinine (DSC), end-stage renal disease (ESRD) or death in patients with hypertension, type 2 diabetes and overt nephropathy compared to amlodipine and control respectively. A simulation model was developed to project long-term cost consequences of the IDNT in the Spanish setting.

METHODS

A Markov model simulated progression from nephropathy to DSC, ESRD and death in patients with hypertension, type 2 diabetes and overt nephropathy. Treatment-specific probabilities were derived from IDNT. Country-specific ESRD-related data were retrieved from published sources. Delay in onset of ESRD, life expectancy and mean lifetime costs were calculated for patients with baseline age 59 years. Future costs were discounted at 6% per annum, and clinical benefits were discounted at 0% and 6% per annum. Extensive sensitivity analyses were performed.

RESULTS

Onset of ESRD was delayed with irbesartan by 1.41 and 1.35 years versus amlodipine and control respectively. When a 25-year (lifetime) horizon was considered, delay in ESRD onset led to anticipated improvements in life expectancy (discounted at 6% shown in brackets) of 0.46 (0.21) years versus amlodipine and 0.75 (0.37) years versus control. Irbesartan was associated with cost savings of 13,673 Euro and 7,632 Euro patient versus amlodipine and control respectively. The results were robust under a wide range of plausible assumptions.

CONCLUSIONS

Treating patients with hypertension, type 2 diabetes and overt nephropathy using irbesartan was both cost- and life-saving compared to amlodipine and control in the Spanish setting.