Abstract P331: Secondary Prevention After Acute Coronary Syndrome with Microsize Myocardial Infarctions in the Reasons for Geographic and Racial Differences in Stroke-Myocardial Infarction (REGARDS-MI) Study

Abstract

Background: Studies have shown increased mortality after myocardial infarction (MI) with low level elevations of cardiac troponin (“microsize MI”) and subsequent risk reduction with intensive medical management. However, non-standard reporting and highly sensitive assays of cardiac troponin can make the clinical recognition of microsize MI difficult, creating barriers to the implementation of appropriate secondary prevention. Methods: REGARDS follows 30,239 community-dwelling participants of the 48 continental states age ≥45 years recruited from 2003-7; 41% of the sample was African American and 55% female by design. Following national consensus guidelines, experts adjudicated cases of acute coronary syndrome (ACS), defined as an admission for acute signs or symptoms of ischemia, and MI from hospital records. We studied first cases of ACS, classified as: 1) ACS without MI, 2) ACS+microsize MI (peak troponin <0.5), and 3) ACS+usual MI (peak troponin ≥0.5), to compare whether secondary prevention medications were prescribed at hospital discharge among these 3 groups. We used multivariable logistic regression to examine odds ratios for receipt of medications at discharge associated with microsize MI and no MI relative to usual MI. Results: The 1,238 cases of ACS were mean age 68.0+/-8.7 years, 59% male, and 66% white. Of these, 917 had discharge medications available. Compared to those with ACS+usual MI, individuals with ACS+microsize MI had lower odds of receiving beta-blockers and statins at discharge in a similar range as those without MI ( Table ). Conclusion: Individuals hospitalized for ACS and microsize MI were less likely to receive guideline appropriate secondary prevention measures than those with usual MI.