Cost-effectiveness of chlorthalidone, amlodipine, and lisinopril as first-step treatment for patients with hypertension: an analysis of the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT).

OBJECTIVE: To evaluate the cost-effectiveness of first-line treatments for hypertension. BACKGROUND: The Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) found that first-line treatment with lisinopril or amlodipine was not significantly superior to chlorthalidone in terms of the primary endpoint, so differences in costs may be critical for optimizing decision-making. METHODS: Cost-effectiveness analysis was performed using bootstrap resampling to evaluate uncertainty. RESULTS: Over a patient's lifetime, chlorthalidone was always least expensive (mean $4,802 less than amlodipine, $3,700 less than lisinopril). Amlodipine provided more life-years (LYs) than chlorthalidone in 84% of bootstrap samples (mean 37 days) at an incremental cost-effectiveness ratio of $48,400 per LY gained. Lisinopril provided fewer LYs than chlorthalidone in 55% of bootstrap samples (mean 7-day loss) despite a higher cost. At a threshold of $50,000 per LY gained, amlodipine was preferred in 50%, chlorthalidone in 40%, and lisinopril in 10% of bootstrap samples, but these findings were highly sensitive to the cost of amlodipine and the cost-effectiveness threshold chosen. Incorporating quality of life did not appreciably alter the results. Overall, no reasonable combination of assumptions led to 1 treatment being preferred in over 90% of bootstrap samples. CONCLUSIONS: Initial treatment with chlorthalidone is less expensive than lisinopril or amlodipine, but amlodipine provided a nonsignificantly greater survival benefit and may be a cost-effective alternative. A randomized trial with power to exclude "clinically important" differences in survival will often have inadequate power to determine the most cost-effective treatment.

Health-related quality of life and cost-effectiveness components of the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial: rationale and design.

Diabetes mellitus affects not only life expectancy but also quality of life. The Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial's health-related quality of life (HRQOL) and cost-effectiveness components will enable the assessment of the relative importance of the various outcomes from the point of view of patients, provide an understanding of the balance between the burdens and benefits of the intervention strategies, and offer valuable insights into adherence. The HRQOL measures used include the Diabetes Symptoms Distress Checklist; the 36-Item Short Form Health Survey, Version 2 (SF-36) (RAND Corporation, Santa Monica, CA); the Patient Health Questionnaire (PHQ) depression measure (Pfizer Inc, New York, NY); the World Health Organization (WHO) Diabetes Treatment Satisfaction Questionnaire (DTSQ); and the EuroQol Feeling Thermometer (EuroQol Group, Rotterdam, Netherlands). The cost-effectiveness analysis (CEA) in ACCORD will provide information about the relative economic efficiency of the different interventions being compared in the trial. Effectiveness will be measured in terms of cardiovascular event-free years gained and quality-adjusted life-years gained (using the Health Utilities Index Mark 3 [HUI-3] [Health Utilities Inc., Dundas, Ontario, Canada] to measure health-state utility). Costs will be direct medical costs assessed from the perspective of a single-payer health system collected by means of patient and clinic cost forms and hospital discharge summaries. The primary HRQOL and CEA hypotheses mirror those in the main ACCORD trial, addressing the effects of the 3 main ACCORD interventions considered separately. There are also secondary (pairwise reference case) comparisons that do not assume independence of treatment effects on HRQOL. CEA will be done on a subsample of 4,311 ACCORD participants and HRQOL on a subsample of 2,053 nested within the CEA subsample. Most assessments will occur through questionnaires at baseline and at 12, 36, and 48 months.