Methods:

The investigators used a retrospective cohort study design of Medicare patients following hospitalization for MI. Medicare beneficiaries aged 66-75 years (n = 29,932) and >75 years (n = 27,956) hospitalized for MI between 2007 and 2012 who filled a high-intensity statin prescription (atorvastatin 40-80 mg, and rosuvastatin 20-40 mg) within 30 days of discharge were studied. Beneficiaries had Medicare fee-for-service coverage including pharmacy benefits. Sociodemographic, dual Medicare/Medicaid coverage, comorbidities, not filling high-intensity statin prescriptions before their MI (i.e., new users), and cardiac rehabilitation and outpatient cardiologist visits after discharge were analyzed. The main outcome measure was high adherence to high-intensity statins at 6 months and 2 years after discharge, which was defined by a proportion of days covered of ≥80%. Down-titration was defined by switching to a low-/moderate-intensity statin with a proportion of days covered of ≥80%, and low adherence was defined by a proportion of days covered <80% for any statin intensity without discontinuation. Discontinuation was defined by not having a statin available to take in the last 60 days of each follow-up period.