A French cost-consequence analysis of the renoprotective benefits of irbesartan in patients with type 2 diabetes and hypertension

Objectives: We performed a cost-consequence analysis in a French setting of the renoprotective benefit of irbesartan in hypertensive type 2 diabetes patients over a 25-year period. Research design and methods: A previously published Markov model simulated progression from microalbuminuria to overt nephropathy, doubling of serum creatinine, end-stage renal disease and death. Three treatment strategies with analogous blood pressure control were compared: (A) control - conventionally medicated antihypertensive therapy (excluding angiotensin converting enzyme inhibitors, other angiotensin-2-receptor antagonists and dihydropyridine calcium channel blockers) initiated at microalbuminuria; (B) early irbesartan - (300 mg daily added to control, initiated with microalbuminuria) and (C) late irbesartan - (300 mg daily, initiated with overt nephropathy). Probabilities came from the Irbesartan in Reduction of Microalbuminuria-2 study, Irbesartan in Diabetic Nephropathy Trial and other sources. Clinical and economic outcomes were projected over 25 years. Annual discount rates were 3%. Results: Compared to control, early use of irbesartan added (mean ± standard deviation) 1.51 ± 0.08 undiscounted life years (discounted: 0.94 ± 0.05 years), while late irbesartan added 0.07 ± 0.01 (0.04 ± 0.01) years/patient. Early irbesartan added 1.03 ± 0.06 discounted quality-adjusted life years (QALYs), while late irbesartan added 0.06 ± 0.01 QALYs. Early and late irbesartan treatments were projected to save €22314 ± 1273 and €6619 ± 820/patient, respectively versus control. Sensitivity analysis showed that even over short time horizons both irbesartan treatments were superior to the control group. Conclusions: In France, early irbesartan treatment improved quality and length of life and reduced costs in hypertensive patients with type 2 diabetes and microalbuminurla. Late irbesartan therapy is beneficial, but earlier irbesartan leads to better outcomes. © 2006 Librapharm Limited.