BACKGROUND: It is unclear whether testing for novel risk factors, such as a cardiovascular genetic risk score (cGRS), improves clinical decision-making or health outcomes when used for targeting statin initiation in the primary prevention of atherosclerotic cardiovascular disease (ASCVD). Our objective was to estimate the cost-effectiveness of cGRS testing to inform clinical decision making about statin initiation in individuals with low to intermediate (2.5% to 7.5%) 10-year predicted risk of ASCVD.
METHODS AND RESULTS: We evaluated the cost-effectiveness of testing for a 27-single nucleotide polymorphism (SNP) cGRS comparing four test/treat strategies: treat all, treat none, test/treat if cGRS is high, and test/treat if cGRS is intermediate or high. We tested a set of clinical scenarios of men and women, aged 45 to 65 years, with 10-year ASCVD risks between 2.5% and 7.5%. Our primary outcome measure was cost per quality-adjusted life-year (QALY) gained. Under base case assumptions for statin disutility and cost, the preferred strategy is to treat all patients with ASCVD risk greater than 2.5% without cGRS testing. For certain clinical scenarios, such as a 57-year-old man with a 10-year ASCVD risk of 7.5%, cGRS testing can be cost-effective under a very limited set of assumptions; for example, when statins cost $15/month and statin disutility is 0.013 (i.e., willing to trade 3 months of life in perfect health to avoid 20 years of statin therapy), the preferred strategy (using a willingness-to-pay (WTP) threshold of $50,000/QALY gained) is to test and treat if cGRS is intermediate or high. Overall, the results were not sensitive to assumptions about statin efficacy and harms.
CONCLUSIONS: Testing for a 27-SNP cGRS is generally not a cost-effective approach for targeting statin therapy in the primary prevention of ASCVD for low to intermediate risk patients.