Economic Evaluation of Angiotensin Receptor Blockers in Type 2 Diabetes, Hypertension, and Nephropathy

There is a rising incidence and prevalence of ESRD as a result of diabetes, with poor outcome and growing costs. Recently, two large trials, the Irbesartan Diabetic Nephropathy Trial (IDNT) and Reduction of Endpoints in NIDDM with the Angiotensin II Antagonist Losartan (RENAAL), showed that angiotensin receptor blockers (ARB) are more effective than traditional antihypertensive therapies at reducing progression toward ESRD in hypertensive patients with type 2 diabetes and overt nephropathy, regardless of changes in BP. The results of these two trials were used to compare the costs of ARB with those of renal replacement therapy (dialysis and renal transplantation) in an effort to establish whether ARB are cost-saving because they delay ESRD. Two different pharmacoeconomic approaches were used. With regard to the RENAAL trial, the number of ESRD days on losartan therapy as compared with the number of ESRD days on standard antihypertensive therapy was calculated, and the difference between the two was combined with the costs of ESRD. In the IDNT trial, Markov models were applied to assess the economic impact of irbesartan and to extrapolate future clinical and cost outcomes. Several economic analyses were performed in the United States and in European countries. Applying pharmacoeconomic models showed that treatment with ARB was associated with a greater improvement in life expectancy and lower total costs compared with amlodipine and standard antihypertensive therapy. Therefore, treating patients with type 2 diabetes, nephropathy, and hypertension with ARB is life- and cost-saving compared with traditional antihypertensive therapy.