Usefulness of Statins as Secondary Prevention Against Recurrent and Terminal Major Adverse Cardiovascular Events

Clinical guidelines recommend statins for patients with atherosclerotic cardiovascular disease (ASCVD), but many remain untreated. The goal of this study was to assess the impact of statin use on recurrent major adverse cardiovascular events (MACE). This study used medical records and insurance claims from 4 health care systems in the United States. Eligible adults who survived an ASCVD hospitalization from September 2013 to September 2014 were followed for 1 year. A multivariable extended Cox model examined the outcome of time-to-first MACE, then a multivariable joint marginal model investigated the association between post-index statin use and nonfatal and fatal MACE. There were 8,168 subjects in this study; 3,866 filled a statin prescription ≤90 days before the index ASCVD event (47.33%) and 4,152 filled a statin prescription after the index ASCVD event (50.83%). These post-index statin users were younger, with more co-morbidities. There were 763 events (315/763, 41.3% terminal) experienced by 686 (8.4%) patients. The adjusted overall MACE risk reduction was 18% (HR 0.82, 95% CI 0.70 to 0.95, p = 0.007) and was more substantial in the first 180 days (HR 0.72, 95% CI 0.60 to 0.86, p <0.001). There was a nonsignificant 19% reduction in the number of nonfatal MACE (rate ratio 0.81, 95% CI 0.49 to 1.32, p = 0.394) and a 65% reduction in the risk of all-cause death (HR 0.35, 95% CI 0.22 to 0.56, p <0.001). In conclusion, we found a modest increase in statin use after an ASCVD event, with nearly half of the patients untreated. The primary benefit of statin use was protection against early death. Statin use had the greatest impact in the first 6 months after an ASCVD event; therefore, it is crucial for patients to quickly adhere to this therapy.