Cardiovascular and Economic Outcomes After Initiation of Atorvastatin versus Simvastatin in an Employed Population Stratified by Cardiovascular Risk

The relative effects of atorvastatin and simvastatin among higher- and lower-risk patients are not well characterized. This study compared cardiovascular (CV) risk and direct and indirect costs among higher- and lower-risk employees initiating atorvastatin vs. simvastatin. Using a large employer claims database (1999-2006), employees were stratified as 1) high-risk employees with prior CV events, diabetes, or renal disorders; and 2) low- to intermediate-risk employees without these conditions. Propensity score matching was used, and 2-year outcomes were compared between matched cohorts. Indirect costs included disability payments and medically related absenteeism. Drug costs were imputed with recent prices to account for availability of generic simvastatin. Among 4167 matched pairs of high-risk employees, atorvastatin use was associated with a numerically lower risk of CV events (17.6 versus 18.4%, P = 0.37), higher direct medical costs ($17,590 versus $17,377, P = 0.002), numerically lower indirect costs ($4830 versus $4989, P = 0.29), and higher total costs by $54 ($22,420 versus $22,366, P = 0.034). The majority of high-risk employees (62%) received low initial statin doses (atorvastatin = 10 mg or simvastatin = 20 mg). Among 9326 matched pairs of low- to intermediate-risk employees, atorvastatin use was associated with a lower risk of CV events (3.1% versus 3.7%, P = 0.030), lower direct medical costs ($8400 versus $8436, P < 0.001), numerically lower indirect costs ($2781 versus $2807; P = 0.12), and lower total costs by $61 ($11,181 versus $11,243, P < 0.001). These results suggest that formulary policies reserving atorvastatin for higher-risk patients may not be cost-saving from the employer perspective.