Cost-Effectiveness of Coronary Artery Calcium Scoring for Cardiovascular Disease Prevention in Diabetes: An Analysis From MESA

Abstract

BACKGROUND: Coronary artery calcium scoring (CACS) by computed tomography could enhance risk assessment and decision making for preventive medication in patients with diabetes. We performed a microsimulation study to compare costs and health outcomes of guideline-based periodic cardiovascular risk assessment with and without CACS. METHODS: We modeled various US guideline-based preventive approaches based on periodically assessed 10-year risk by pooled cohort equations with and without CACS. We predicted cumulative costs and quality-adjusted life years (QALYs) until age 100 years from the US health care sector perspective in MESA (Multi-Ethnic Study of Atherosclerosis) participants aged 45 to 84 years with diabetes (n=853), who were weighted to represent the US general patient population. Probabilistic and deterministic sensitivity analyses were performed to address uncertainty. RESULTS: Initiating high-intensity statins regardless of risk and low-dose aspirin if 10-year risk ≥10% led to the largest QALY gains with incremental cost-effectiveness ratios of $35 000 to $40 000/QALY. When omitting such universal approaches, allocating high-intensity statins and low-dose aspirin if CACS ≥100 led to incremental cost-effectiveness ratios around $50 000/ QALY. Ranking of strategies by cost-effectiveness was generally robust against parameter uncertainty. The incremental cost-effectiveness ratio of the CACS ≥100 strategy fell below $50 000/QALY if the fee of CACS fell below $75 or when statin continuation was assumed to significantly improve with nonzero CAC scores. CONCLUSIONS: Broadening the use of high-intensity statins and low-dose aspirin in patients aged 45 to 84 years with diabetes can be considered cost-effective. If broad-scale use of intensive preventive treatment is either not feasible or not desired, then CACS may be cost-effective in refining preventive treatment decisions.