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, but recent data about the risk of new-onset diabetes mellitus have raised concerns about its use. Our main objective was to evaluate the association between intensive statin therapy and new-onset diabetes mellitus in patients with myocardial infarction 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 with myocardial infarction aged >65 years old, hospitalized 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 acute coronary syndrome 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 acute coronary syndrome ( 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, we found intensive-dose statin therapy to be effective in reducing repeat hospitalization for acute coronary syndrome. The rate of new-onset diabetes mellitus at long term was not significantly different between intensive-dose and moderate-dose statins.