We aimed to quantify for the first time the relationship between statin adherence and ischemic stroke (IS) in patients with diabetes.
Using Finnish health registers, we assembled a cohort of 52?868 statin initiators with diabetes in 1995-2006. We conducted a nested case-control analysis matching cases with IS with up to four controls for age, sex, date of statin initiation and follow-up duration. Adjusted rate ratios for IS were estimated with conditional logistic regression. Additional potential confounders were considered with inverse probability weighting and the role of unmeasured confounding using external adjustment. Statin adherence was measured as the proportion of days covered (PDC).
Among 1703 cases and 6799 controls, good adherence to statins (PDC?=?80%) was associated with a 23% decreased incidence of IS (95%CI 14-32%) compared with poor adherence (PDC?