Background: Although documented traditional cardiovascular risk factors (hypertension, diabetes, smoking, and dyslipidemia) increase the risk of developing coronary artery disease, their influence on the treatments and outcomes of patients with non-ST-segment elevation myocardial infarction (NSTEMI) has not been fully elucidated.
Methods: Using data from the CRUSADE Quality Improvement Initiative, we sought to characterize the effect that the absence of documented traditional risk factors has on inhospital treatments and outcomes in a population of patients with NSTEMI treated in routine practice. We compared clinical characteristics and inhospital outcomes according to the presence and number of risk factors in 74,220 patients with NSTEMI (defined as creatine kinase-MB and/or troponin I/T values above the local upper limit of normal) treated in 476 US hospitals from January 2001 through March 2004.
Results: The 7755 (10.5%) patients with no documented traditional risk factors on admission were less likely to receive short-term guideline-recommended therapies and revascularization procedures. Despite a higher prevalence of normal left ventricular function and insignificant angiographic coronary artery disease, these patients had a slightly higher risk of adjusted inhospital mortality (odds ratio 1.15, 95% CI 1.03-1.29) compared with patients with any combination of risk factors.
Conclusions: Patients without documented traditional cardiovascular risk factors represent 10.5% of the non-ST-segment elevation myocardial infarction population. Because the absence of documented traditional risk factors does not yield a favorable prognosis, further study is needed to delineate the effects of the interplay between novel and documented traditional risk factors and treatment differences on the outcomes of these patients.