Introduction: Recent interest has focused on STEMI patients (pts) without standard modifiable risk factors (SMuRF-less), noting that they are surprisingly common (14-27%). These studies have reported them to have a worse, or at best similar, in-hospital/short-term prognosis. However, relatively little attention has been paid to the prevalence and prognosis of SMuRF-less patients with non-ST elevation myocardial infarction (NSTEMI). The aim of our study was to identify the proportion and outcomes of SMuRF-less NSTEMI pts in a large US healthcare population. Methods: Pts with NSTEMI between 2001-2021 presenting to Intermountain Healthcare catheterization laboratories were included. SMuRF included a clinical diagnosis of, or treatment for, hypertension, hyperlipidemia, diabetes, and/or smoking. 60-day and long-term major adverse cardiovascular event (MACE) outcomes were defined as death, myocardial infarction, and heart failure hospitalization and were tested using Cox proportional hazard regression. Results: NSTEMI pts totaled 8196, of which1458 (17.8%) were SMuRF-less. SMuRF-less pts were younger, more frequently male, had fewer comorbidities, and were slightly less likely to have PCI/CABG than NSTEMI pts with SMuRF (Table 1). 60-day MACE for SMuRF-less pts were lower (adj HR 0.55, p<0.0001), and this persisted for long-term MACE outcomes (adj HR 0.64, p<0.0001) and for each of its components (Table 2). Conclusions: In this large US healthcare population, SMuRF-less NSTEMI presentation, as with STEMI presentation, was found to be common (17.8%). However, unlike STEMI reports, short- and long-term outcomes were generally more favorable for SMuRF-less status. Further studies to increase understanding of risk factors and preventive measures for NSTEMI in SMuRF-less pts are indicated.
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