Predictors and mid-term outcomes of nosocomial infection in ST-elevation myocardial infarction patients treated by primary angioplasty

Background: Nosocomial infections (NI) are associated with high morbidity and mortality. Existing data on the impact of NI on patients with ST-elevation myocardial infarction (STEMI) is scarce. Aim: Our aim was to determine the incidence, predictors, and prognosis of NI in a contemporary series of STEMI patients.Methods: 1131 consecutive STEMI patients treated by primary percutaneous coronary intervention from January 2008 to December 2017 were analyzed. Binary logistic regression and Cox proportional hazard models were used to identify predictors of NI and major adverse cardio-cerebrovascular events (MACCE) at 1-year follow-up, respectively.Results: Of all patients, 126 (11.1%) were diagnosed with NI (>48 hours from admission), mostly of respiratory (50.8%) and urinary (39.7%) tract origin. Insulin-treated diabetics were 3-fold more likely to develop NI. Other independent predictors were peripheral arterial disease, intra-aortic balloon pump insertion, age, lower systolic blood pressure, and higher peak creatine-kinase. Only pre-infarction angina was negatively related to NI. Age, peripheral arterial disease, femoral approach and larger infarct were related to MACCE at 1-year follow-up. NI in isolation was not independently related to MACCE (hazard ratio [HR], 1.24; 95% confidence interval [CI], 0.80–1.94; P = 0.34). However, we found a significant interaction between NI and smoking (HR, 2.33; 95% CI, 1.03–5.24; Pinterc = 0.04).Conclusion: Larger infarct size, hemodynamic instability, and co-morbidities were related to both NI and 1-year adverse events. Smokers who developed NI also had a higher 1-year risk of MACCE.