Cost-effectiveness of Low-density Lipoprotein Cholesterol Level–Guided Statin Treatment in Patients With Borderline Cardiovascular Risk

Abstract

Would extending statin therapy to patients with borderline 10-year absolute risk of atherosclerotic cardiovascular disease (5.0%-7.4%) and high levels of low-density lipoprotein cholesterol be cost-effective? This microsimulation cohort study of 100 cohorts, each including 1 million hypothetical patients, found that adding treatment of patients with borderline risk and low-density lipoprotein cholesterol levels of 160 to 189 mg/dL to standard care would be cost-saving; treating patients at borderline risk with low-density lipoprotein cholesterol levels of 130 to 159 mg/dL would be cost-saving; and treating all patients at borderline risk, regardless of low-density lipoprotein cholesterol level, would be highly cost-effective. Results suggest that statin therapy for patients at borderline risk of ASCVD and with a low-density lipoprotein cholesterol level of 160 mg/dL or more could yield lifetime health benefits similar to those achieved by treating higher-risk patients with lower low-density lipoprotein cholesterol levels and could save health care costs. This simulation cohort study estimates the cost-effectiveness of adding preventive statin treatment to standard care of patients at borderline risk of atherosclerotic cardiovascular disease with high levels of low-density lipoprotein cholesterol and the cost-effectiveness of statin treatment across population strata. American College of Cardiology/American Heart Association cholesterol guidelines prioritize primary prevention statin therapy based on 10-year absolute risk (AR 10 ) of atherosclerotic cardiovascular disease (ASCVD). However, given the same AR 10 , patients with higher levels of low-density lipoprotein cholesterol (LDL-C) experience greater absolute risk reduction from statin therapy. To estimate the cost-effectiveness of expanding preventive statin treatment eligibility from standard care to patients at borderline risk (AR 10 , 5.0%-7.4%) for ASCVD and with high levels of LDL-C and to estimate cost-effectiveness of statin treatment across ranges of age, sex, AR 10 , and LDL-C levels. This study evaluated 100 simulated cohorts, each including 1 million ASCVD-free survey respondents (50% men and 50% women) aged 40 years at baseline. Cohorts were created by probabilistic sampling of the 1999-2014 US National Health and Nutrition Examination Surveys from the perspective of the US health care sector. The CVD Policy Model microsimulation version projected lifetime health and cost outcomes. Probability of first-ever coronary heart disease or stroke event was estimated by analysis of 6 pooled US cohort studies and recalibrated to match contemporary event rates. Other model variables were derived from national surveys, meta-analyses, and published literature. Data were analyzed from May 15, 2018, through June 10, 2019. Four statin treatment strategies were compared: (1) treat all patients with AR 10 of at least 7.5%, diabetes, or LDL-C of at least 190 mg/dL (standard care); (2) add treatment for borderline risk and LDL-C levels of 160 to 189 mg/dL; (3) add treatment for borderline risk and LDL-C levels of 130 to 159 mg/dL; and (4) add treatment for remainder of patients with AR 10 of at least 5.0%. Statin treatment was also compared with no statin treatment in age, sex, AR 10 , and LDL-C strata. Lifetime quality-adjusted life-years (QALYs) and costs (2019 US dollars) were projected and discounted 3.0% annually. The primary outcome was the incremental cost-effectiveness ratio. In these 100 simulated cohorts, each with 1 million patients aged 40 years at baseline (50% women and 50% men), adding preventive statins to individuals with borderline AR 10 and LDL-C levels of 160 to 189 mg/dL would be cost-saving; further treating borderline AR 10 and LDL-C levels of 130 to 159 mg/dL would also be cost-saving; and treating all individuals with AR 10 of at least 5.0% would be highly cost-effective ($33 558/QALY) and would prevent the most ASCVD events. Within age, AR 10 , and sex categories, individuals with higher baseline LDL-C levels gained more QALYs from statin therapy. Cost-effectiveness increased with LDL-C level and AR 10 . In this study, lifetime statin treatment of patients in a hypothetical cohort with borderline ASCVD risk and LDL-C levels of 160 to 189 mg/dL was found to be cost-saving. Results suggest that treating all patients at borderline risk regardless of LDL-C level would likely be highly cost-effective.