Number of coronary heart disease risk factors and mortality in patients with first myocardial infarction.

CONTEXT: Few studies have examined the association between the number of coronary heart disease risk factors and outcomes of acute myocardial infarction in community practice. OBJECTIVE: To determine the association between the number of coronary heart disease risk factors in patients with first myocardial infarction and hospital mortality. DESIGN: Observational study from the National Registry of Myocardial Infarction, 1994-2006. PATIENTS: We examined the presence and absence of 5 major traditional coronary heart disease risk factors (hypertension, smoking, dyslipidemia, diabetes, and family history of coronary heart disease) and hospital mortality among 542,008 patients with first myocardial infarction and without prior cardiovascular disease. MAIN OUTCOME MEASURE: All-cause in-hospital mortality. RESULTS: A majority (85.6%) of patients who presented with initial myocardial infarction had at least 1 of the 5 coronary heart disease risk factors, and 14.4% had none of the 5 risk factors. Age varied inversely with the number of coronary heart disease risk factors, from a mean age of 71.5 years with 0 risk factors to 56.7 years with 5 risk factors (P for trend < .001). The total number of in-hospital deaths for all causes was 50,788. Unadjusted in-hospital mortality rates were 14.9%, 10.9%, 7.9%, 5.3%, 4.2%, and 3.6% for patients with 0, 1, 2, 3, 4, and 5 risk factors, respectively. After adjusting for age and other clinical factors, there was an inverse association between the number of coronary heart disease risk factors and hospital mortality adjusted odds ratio (1.54; 95% CI, 1.23-1.94) among individuals with 0 vs 5 risk factors. This association was consistent among several age strata and important patient subgroups. CONCLUSION: Among patients with incident acute myocardial infarction without prior cardiovascular disease, in-hospital mortality was inversely related to the number of coronary heart disease risk factors.

Atherosclerotic risk factors and their association with hospital mortality among patients with first myocardial infarction (from the National Registry of Myocardial Infarction).

Few studies have examined associations between atherosclerotic risk factors and short-term mortality after first myocardial infarction (MI). Histories of 5 traditional atherosclerotic risk factors at presentation (diabetes, hypertension, smoking, dyslipidemia, and family history of premature heart disease) and hospital mortality were examined among 542,008 patients with first MIs in the National Registry of Myocardial Infarction (1994 to 2006). On initial MI presentation, history of hypertension (52.3%) was most common, followed by smoking (31.3%). The least common risk factor was diabetes (22.4%). Crude mortality was highest in patients with MI with diabetes (11.9%) and hypertension (9.8%) and lowest in those with smoking histories (5.4%) and dyslipidemia (4.6%). The inclusion of 5 atherosclerotic risk factors in a stepwise multivariate model contributed little toward predicting hospital mortality over age alone (C-statistic = 0.73 and 0.71, respectively). After extensive multivariate adjustments for clinical and sociodemographic factors, patients with MI with diabetes had higher odds of dying (odds ratio [OR] 1.23, 95% confidence interval [CI] 1.20 to 1.26) than those without diabetes and similarly for hypertension (OR 1.08, 95% CI 1.06 to 1.11). Conversely, family history (OR 0.71, 95% CI 0.69 to 0.73), dyslipidemia (OR 0.62, 95% CI 0.60 to 0.64), and smoking (OR 0.85, 95% CI 0.83 to 0.88) were associated with decreased mortality (C-statistic = 0.82 for the full model). In conclusion, in the setting of acute MI, histories of diabetes and hypertension are associated with higher hospital mortality, but the inclusion of atherosclerotic risk factors in models of hospital mortality does not improve predictive ability beyond other major clinical and sociodemographic characteristics.