Mortality Rate Increases Steeply With Nonadherence to Statin Therapy in Patients With Acute Coronary Syndrome

BACKGROUND: In a prospective cohort of consecutive acute coronary syndrome (ACS) patients, we compared the adherence rate of statin usage and mortality rate during a median follow-up of 23 months. HYPOTHESIS: Adherence to statin therapy after acute coronary syndrome affects mortality rate. METHODS: We analyzed ACS patients (N = 1969; age, 65.9 ± 11.8 years; female 30.4%) who underwent angiography between March 2006 and March 2008. The postdischarge usage of statins was based on the purchase register of the Social Insurance Institution of Finland. The death rate was verified from Statistics Finland. RESULTS: At discharge, the rate of statin prescription to patients was 95.4% (n = 1878). When comparing adherent patients (n = 1200; 61.7%), who purchased the medication systematically until the end of the median 23-month follow-up, with nonadherent patients (n = 94; 4.8%), who did not use the medication at all, there was a vast difference in absolute death rate between the groups: 4.9% vs 14.9%, respectively (P < 0.001). We conducted Cox proportional hazards model with ACS type, cerebrovascular attack, diabetes, age, 3-artery disease, and cancer as adjusted confounders. Compared with regular statin users, nonusers were associated with a >2× increased hazard ratio of mortality (hazard ratio: 2.70, 95% confidence interval: 1.49-4.90, P = 0.001). CONCLUSIONS: Statin medication is essential for discharged ACS patients. They should be strongly encouraged to purchase and use it.