Cost-effectiveness of early irbesartan treatment versus control (standard antihypertensive medications excluding ACE inhibitors, other angiotensin-2 receptor antagonists, and dihydropyridine calcium channel blockers) or late irbesartan treatment in patients with type 2 diabetes, hypertension, and renal disease.
OBJECTIVE
The aim of this study was to determine the most cost-effective time point for initiation of irbesartan treatment in hypertensive patients with type 2 diabetes and renal disease.


METHODS
This study was a Markov model-simulated progression from microalbuminuria to overt nephropathy, doubling of serum creatinine, end-stage renal disease, and death in hypertensive patients with type 2 diabetes. Two irbesartan strategies were created: early irbesartan 300 mg daily (initiated with microalbuminuria) and late irbesartan (initiated with overt nephropathy). These strategies were compared with control, which consisted of antihypertensive therapy with standard medications (excluding ACE inhibitors, other angiotensin-2 receptor antagonists, and dihydropyridine calcium channel blockers) with comparable blood pressure control, initiated at microalbuminuria. Transition probabilities were taken from the Irbesartan in Reduction of Microalbuminuria-2 study, Irbesartan in Diabetic Nephropathy Trial, and other published sources. Costs and life expectancy, discounted at 3% yearly, were projected over 25 years for 1,000 simulated patients using a third-party payer perspective in a U.S. setting.


RESULTS
Compared with control, early and late irbesartan treatment in 1,000 patients were projected to save (mean +/- SD) 11.9 +/- 3.3 million dollars and 3.3 +/- 2.7 million dollars, respectively. Early use of irbesartan added 1,550 +/- 270 undiscounted life-years (discounted 960 +/- 180), whereas late irbesartan added 71 +/- 40 life-years (discounted 48 +/- 27) in 1,000 patients. Early irbesartan treatment was superior under a wide-range of plausible assumptions.


CONCLUSIONS
Early irbesartan treatment was projected to improve life expectancy and reduce costs in hypertensive patients with type 2 diabetes and microalbuminuria. Later use of irbesartan in overt nephropathy is also superior to standard care, but irbesartan should be started earlier and continued long term.
Palmer
Andrew J
AJ
CORE-Center for Outcomes Research, Buendtenmattstrasse 40, 4102 Binningen/Basel, Switzerland. ap@thecenter.ch
Annemans
Lieven
L
Roze
Stéphane
S
Lamotte
Mark
M
Lapuerta
Pablo
P
Chen
Roland
R
Gabriel
Sylvie
S
Carita
Paulo
P
Rodby
Roger A
RA
de Zeeuw
Dick
D
Parving
Hans-Henrik
HH
D000806:Angiotensin-Converting Enzyme Inhibitors / Q000627:therapeutic use; D000959:Antihypertensive Agents / Q000191:economics / Q000627:therapeutic use*; D001713:Biphenyl Compounds / Q000191:economics / Q000627:therapeutic use*; D002121:Calcium Channel Blockers / Q000627:therapeutic use; D003362:Cost-Benefit Analysis; D003404:Creatinine / Q000097:blood; D003924:Diabetes Mellitus, Type 2 / Q000191:economics / Q000401:mortality / Q000503:physiopathology*; D003925:Diabetic Angiopathies / Q000188:drug therapy*; D003928:Diabetic Nephropathies / Q000150:complications*; D018450:Disease Progression; D006801:Humans; D006973:Hypertension / Q000188:drug therapy* / Q000191:economics; D000077405:Irbesartan; D008390:Markov Chains; D008962:Models, Theoretical; D012051:Reimbursement Mechanisms; D016019:Survival Analysis; D013777:Tetrazoles / Q000191:economics / Q000627:therapeutic use*; D014481:United States
D000806:Angiotensin-Converting Enzyme Inhibitors; D000959:Antihypertensive Agents; D001713:Biphenyl Compounds; D002121:Calcium Channel Blockers; D013777:Tetrazoles; D003404:Creatinine; D000077405:Irbesartan