Cost-effectiveness of cholesterol-lowering therapies according to selected patient characteristics

Background: The National Cholesterol Education Program Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel II) recommends treatment guidelines based on cholesterol level and number of risk factors. Objective: To evaluate how the cost-effectiveness ratios of cholesterol-lowering therapies vary according to different risk factors. Design: Cost-effectiveness analysis. Data Sources: Published data. Target Population: Women and men 35 to 84 years of age with low-density lipoprotein cholesterol levels of 4.1 mmol/L or greater (greater than or equal to 160 mg/dL), divided into 240 risk subgroups according to age, sex, and the presence or absence of four coronary heart disease risk factors (smoking status, blood pressure, low-density lipoprotein cholesterol level, and high-density lipoprotein cholesterol level). Time Horizon: 30 years. Perspective: Societal. Interventions: Step I diet, statin therapy, and no preventive treatment for primary and secondary prevention. Outcome Measures: Incremental cost-effectiveness ratios. Results of Base-Case Analysis: Incremental cost-effectiveness ratios for primary prevention with step I diet ranged from $1900 per quality-adjusted life-year (QALY) gained to $500 000 per QALY depending on risk subgroup characteristics. Primary prevention with a statin compared with diet therapy was $54 000 per QALY to $1 400 000 per QALY. Secondary prevention with a statin cost less than $50 000 per QALY for all risk subgroups. Results of Sensitivity Analysis: The inclusion of niacin as a primary prevention option resulted in much less favorable incremental cost-effectiveness ratios for primary prevention with a statin (>$500 000 per QALY). Conclusions: Cost-effectiveness of treatment strategies varies significantly when adjusted for age, sex, and the presence or absence of additional risk factors. Primary prevention with a step I diet seems to be cost-effective for most risk subgroups but may not be cost-effective for otherwise healthy young women. Primary prevention with a statin may not be cost-effective for younger men and women with few risk factors, given the option of secondary prevention and of primary prevention in older age ranges. Secondary prevention with a statin seems to be cost-effective for all risk subgroups and is cost-saving in some high-risk subgroups.