Purpose: Compare medical expenditures among adults with statin-associated adverse effects (SAAE) and high statin adherence (HSA) following myocardial infarction (MI).
Methods: We analyzed expenditures in 2016 US dollars among Medicare beneficiaries with SAAE (n = 1741) and HSA (n = 55,567) who were ≥ 66 years of age and initiated moderate/high-intensity statins following an MI in 2007-2013. SAAE were identified through a claims-based algorithm, which included down-titrating statins and initiating ezetimibe, switching to ezetimibe monotherapy, having a rhabdomyolysis or antihyperlipidemic adverse event followed by statin down-titration or discontinuation, or switching between ≥ 3 statin types within 365 days following MI. HSA was defined by having a statin available to take for ≥ 80% of the days in the 365 days following MI.
Results: Expenditures among beneficiaries with SAAE and HSA were $40,776 (95% CI $38,329-$43,223) and $26,728 ($26,482-$26,974), respectively, in the 365 days following MI, and $34,238 ($31,396-$37,080) and $29,053 ($28,605-$29,500), respectively, for every year after the first 365 days. Multivariable-adjusted ratios comparing expenditures among beneficiaries with SAAE versus HSA in the first 365 days and after the first 365 days following MI were 1.51 (95% CI 1.43-1.59) and 1.23 (1.12-1.34), respectively. Inpatient and outpatient expenditures were higher among beneficiaries with SAAE versus HSA during and after the first 365 days following MI. Compared to beneficiaries with HSA, medication expenditures among those with SAAE were similar in the 365 days following MI, but higher afterwards. Other medical expenditures were higher among beneficiaries with SAAE versus HSA.
Conclusion: SAAE are associated with increased expenditures following MI compared with HSA.
Keywords: Adverse effects; Cost and cost analysis; Hydroxymethylglutaryl-CoA reductase inhibitors; Medicare; Myocardial infarction.