Health Services and Outcomes Research Using Stress Testing to Guide Primary Prevention of Coronary Heart Disease Among Intermediate-Risk Patients A Cost-Effectiveness Analysis

Background—Noninvasive stress testing might guide the use of aspirin and statins for primary prevention of coronary heart disease, but it is unclear if such a strategy would be cost effective. Methods and Results—We compared the status quo, in which the current national use of aspirin and statins was simulated, with 3 other strategies: (1) full implementation of Adult Treatment Panel III guidelines, (2) a treat-all strategy in which all intermediate-risk persons received statins (men and women) and aspirin (men only), and (3) a test-and-treat strategy in which all persons with an intermediate risk of coronary heart disease underwent stress testing and those with a positive test were treated with high-intensity statins (men and women) and aspirin (men only). Healthcare costs, coronary heart disease events, and quality-adjusted life years from 2011 to 2040 were projected. Under a variety of assumptions, the treat-all strategy was the most effective and least expensive strategy. Stress electrocardiography was more effective and less expensive than other test-and-treat strategies, but it was less expensive than treat all only if statin cost exceeded $3.16/pill or if testing increased adherence from Ͻ22% to Ͼ75%. However, stress electrocardiography could be cost effective in persons initially nonadherent to the treat-all strategy if it raised their adherence to 5% and cost saving if it raised their adherence to 13%. Conclusions—When generic high-potency statins are available, noninvasive cardiac stress testing to target preventive medications is not cost effective unless it substantially improves adherence. A lthough coronary heart disease (CHD) mortality has declined in the United States over recent decades, a substantial proportion of CHD remains attributed to hy-percholesterolemia. 1 National guidelines for lipid-lowering and aspirin prophylaxis for the primary prevention of CHD have proven effectiveness in high-risk patients whereas costs and potential adverse side effects have tempered enthusiasm for treating low-risk individuals. 2–5 Less clear is the approach for intermediate-risk patients (10% to 20% ten-year risk of CHD), even though this group constitutes the largest population recommended for primary prevention with lipid-lowering agents and aspirin under current guidelines. 3 On the basis of the declining cost of statins, pharmacological lipid lowering may now be cost effective for primary prevention for the large intermediate-risk population. 6,7 Noninvasive cardiac stress testing can improve risk stratification of intermediate-risk patients. 8 –10 A positive test may identify intermediate-risk patients who would benefit from more-intensive risk factor modification, whereas negative test results may identify people appropriate for lower-intensity …