Abstract 10681: Prior Myocardial Infarction as a Risk Factor for in-Hospital Cardiovascular Outcomes: Analysis of National Registry of Myocardial Infarction 4 and 5
Background Patients with acute coronary syndromes are at continued risk for future cardiovascular (CV) events. However, in the setting of acute coronary syndromes, the relationship between prior myocardial infarction (MI) and subsequent in-hospital adverse CV outcomes has not been definitively established.
Methods We analyzed data from 232,927 hospitalized patients presenting with acute MI (AMI) between July 2002 and December 2006, enrolled in the National Registry of Myocardial Infarction (NRMI 4-5). Multivariable logistic regression models were developed to examine the association between prior history of MI and in-hospital all-cause mortality and recurrent MI, with adjustment for multiple risk factors including demographic characteristics, pre-arrival medications, comorbidities, and health status at presentation.
Results Among the 232,927 AMI patients studied, there were 57, 492 (35%) who had a history of prior MI. Patients with ST-segment elevation myocardial infarction (STEMI) represented 37% (86,761) of the total cohort studied. Reported use of pre-admission medications was higher in patients with a history of prior MI; yet, only 48% reported use of ACE inhibitors/ARBs, 51% for aspirin, 39% for beta blockers, and 33% for statins. In-hospital mortality was not significantly different in patients with and without a history of prior MI (adjusted odds ratio [OR] 1.01, 95% confidence interval [CI]: 0.97-1.06, p=0.58], despite differences in revascularization strategy for reperfusion-eligible patients. However, patients with prior MI had a small increase in risk of in-hospital recurrent MI compared to patients with no prior history (adjusted OR 1.18, 95% CI: 1.09-1.29, p< 0.001).
Conclusion History of prior MI did not significantly affect in-hospital mortality following admission for an AMI. However, the odds of a recurrent MI in-hospital were greater for patients with a prior history of MI than for those without such a history. Additional longitudinal analyses may further elucidate the role of previous MI in subsequent CV risk.
- © 2011 by American Heart Association, Inc.