Diabetes mellitus and cardiovascular events in older patients with myocardial infarction prescribed intensive-dose and moderate-dose statins

Background — Practice guidelines recommend intensive-dose statins for patients with acute coronary syndrome (ACS), but recent data about the risk of new-onset diabetes have raised concern about its use. The authors' main objective was to evaluate the association between intensive statin therapy and new-onset diabetes in myocardial infarction patients, and to evaluate the association of intensive statin therapy with long-term adverse clinical outcomes.

Methods and Results — A propensity score matched cohort was created consisting of 17,080 patients older than 65 years old, hospitalized with a myocardial infarction in Ontario, Canada from 2004 to 2010. Clinical outcomes were compared in patients prescribed intensive-dose versus moderate-dose statins at hospital discharge. At 5 years, 13.6% of patients receiving intensive-dose statins and 13.0% of patients receiving moderate-dose statins had new-onset diabetes, which was not significantly different (p = 0.19). By contrast, the 5-year rate of death or ACS was significantly lower at 44.8% in the intensive-dose statin group compared with 46.5% in the moderate-dose group (p = 0.044). The reduction in combined clinical outcome was driven mainly by a significantly lower rate of ACS (p = 0.039) associated with intensive-dose statins. No significant difference in mortality rates (34.8% in both groups) was observed between the treatment groups during the study period (p = 0.89).

Conclusions — In older patients with myocardial infarction, the authors found intensive-dose statin therapy to be effective in reducing repeat hospitalization for ACS. The rate of new-onset diabetes at long term was not significantly different between intensive-dose and moderate-dose statins.