Clinical outcomes of ST elevation myocardial infarction patients without standard modifiable risk factors

Background

Standard modifiable cardiovascular risk factors (SMuRFs; hypertension, diabetes mellitus, dyslipidemia, and smoking) are widely recognized as risk factors for coronary artery disease. However, the associations between absence of SMuRFs and long-term clinical outcomes in ST-segment elevation myocardial infarction (STEMI) patients are unclear.

Methods

Consecutive STEMI patients who underwent primary percutaneous coronary intervention (PCI) between 1999 and 2015 were retrospectively analyzed. The primary endpoint was up to 5-year all-cause mortality. Clinical characteristics and outcomes were compared between patients with at least one of the SMuRFs and those without any SMuRFs.

Results

Of 1963 STEMI patients, 126 (6.4 %) did not have any SMuRFs. Patients without SMuRFs were significantly older, had lower body mass index, and were more likely to be female. During a median follow-up period of 4.9 years, the cumulative incidence of death was significantly higher in patients without SMuRFs than in those with SMuRFs (log-rank p < 0.0001). Landmark analysis showed that patients without SMuRFs had higher mortality within 30 days of STEMI onset (log-rank p = 0.0045) and >30 days after STEMI onset (log-rank p = 0.0004). Multivariable Cox hazards analysis showed that absence of SMuRFs was associated with a higher risk of mortality (hazard ratio, 1.59; 95 % confidence interval, 1.14–2.21; p = 0.006).

Conclusions

Of STEMI patients undergoing primary PCI, patients without any SMuRFs had higher mortality than those with at least one of the SMuRFs. Patients without any SMuRFs have a poor prognosis and require more attention.