Results:

A total of 6,116 patients with an ischemic stroke were identified, and 1,446 had AF. The mean prescription days covered for statin use was 85 for the cohort, and patients were stratified by <85 prescription days covered (n = 1,853) and ≥85 prescription days covered (n = 4,263). At baseline, higher prescription days covered was associated with older age, diagnosis of AF, coronary artery disease, diabetes mellitus, and heart failure. Statin adherence was lower in Black and Hispanic patients. Low-density lipoprotein (LDL) cholesterol was used as a surrogate to validate the statin prescription days covered measure. As expected, a higher prescription days covered for statin use was associated with a greater likelihood of achieving a 30 mg/dL reduction in LDL cholesterol. A multivariable survival model, after controlling for gender, race/ethnicity, comorbidities, and hospital center, found that higher statin adherence was associated with a 41% relative risk reduction (hazard ratio [HR] 0.59; 95% confidence interval [CI], 0.43-0.81; p = 0.001) in ischemic stroke risk in patients with AF and a 22% relative risk reduction (HR 0.78; 95% CI, 0.63-0.97; p = 0.023) in ischemic stroke risk in patients without AF. Furthermore, similar reductions in ischemic stroke risk (HR 0.61; 95% CI, 0.41-9.90; p = 0.012; n = 1,010) were observed in a subgroup of patients with AF who were receiving warfarin, after adjusting for time in therapeutic range.