COST-EFFECTIVENESS OF CAPTOPRIL THERAPY AFTER MYOCARDIAL-INFARCTION

Objectives. This study sought to assess the cost-effectiveness of capt opril therapy for survivors of myocardial infarction. Background. The recent randomized, controlled Survival and Ventricular Enlargement (SA VE) trial shelved that captopril therapy improves survival in survivor s of myocardial infarction with an ejection fraction less than or equa l to 40%. The present ancillary study was designed to determine how th e costs required to achieve this increase in survival compared with th ose of other medical interventions. Methods. We developed a decision a nalytic model to assess the cost-effectiveness of captopril therapy in 50- to 80-year old survivors of myocardial infarction with an ejectio n fraction less than or equal to 40%. Data on costs, utilities (health related quality of life weights) and 4-year survival were obtained di rectly from the SAVE trial, and long-term survival was estimated using a Markov model. In one set of analyses, we assumed that the survival benefit associated with captopril therapy would persist beyond 4 years (persistent benefit analyses), whereas in another set we assumed that captopril therapy incurred costs but no survival benefit beyond 4 yea rs (limited benefit analyses). Results. In the limited-benefit analyse s, the incremental cost-effectiveness of captopril therapy ranged from $3,600/quality-adjusted life year for 80-year old patients to $60,800 /quality-adjusted life-year for 50-year old patients. In the persisten t-benefit analyses, incremental cost effectiveness ratios ranged from $3,700 to $10,400/quality adjusted life-year, depending on age. The ou tcome was generally not sensitive to changes in estimates of variables when they were varied individually over wide ranges. In a ''worst-cas e'' analysis, incremental cost-effectiveness ratios for captopril ther apy remained favorable ($8,700 to $29,200/quality-adjusted life-year) for 60- to 80-year old patients but were higher ($217,600/quality-adju sted life-year) for 50-year old patients.Conclusions. We conclude that the cost-effectiveness of captopril therapy for 50- to 80-year old su rvivors of myocardial infarction with a low ejection fraction compares favorably with other interventions for survivors of myocardial infarc tion.