Abstract P90: Cardiovascular and Economic Outcomes Following Initiation of Atorvastatin versus Simvastatin in an Employed Population Stratified by Cardiovascular Risk
OBJECTIVE: To compare initiation with atorvastatin versus simvastatin among higher- and lower-risk employees in terms of subsequent risk of cardiovascular (CV) events and direct and indirect costs from the employer perspective. METHODS: Employees initiating atorvastatin or simvastatin were identified from a claims database (1999-2006) spanning 23 large, self-insured employers and 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 to adjust for baseline differences between the atorvastatin and simvastatin cohorts, and two-year outcomes were compared between matched cohorts. Indirect costs included disability payments and medically-related absenteeism. Atorvastatin and simvastatin drug costs were imputed with recent prices to account for availability of generic simvastatin. RESULTS: Among 4,167 matched pairs of high-risk employees, initiation with atorvastatin vs. simvastatin was associated with similar rates of subsequent CV events (17.6 vs. 18.4%, P=0.37), higher direct medical costs ($17,590 vs. $17,377, P=0.002), similar indirect costs ($4,830 vs. $4,989, P=0.29) and higher total costs by $54 ($22,420 vs. $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 9,326 matched pairs of low-to-intermediate risk employees, initiation with atorvastatin vs. simvastatin was associated with a lower rate of CV events (3.1 vs. 3.7%, p=0.030), lower direct medical costs ($8,400 vs. $8,436, P<0.001), similar indirect costs ($2,781 vs. $2,807; P=0.12) and lower total costs by $61 ($11,181 vs. $11,243, P<0.001). CONCLUSIONS: Among high-risk patients, initiation with atorvastatin vs. simvastatin was associated with no significant difference in CV events and higher total costs to employers. Among low-to-intermediate risk patients, initiation with atorvastatin vs. simvastatin was associated with fewer CV events and net cost savings to employers. Formulary policies reserving atorvastatin for higher-risk patients may not be beneficial from the employer perspective.