Risk Factors for 30-Day Mortality in Patients with Methicillin-Resistant Staphylococcus aureus Bloodstream Infections

•The aim of this study was to identify risk factors associated with 30-day mortality in patients with MRSA BSI.•1,168 patients with confirmed MRSA BSI were identified over a 9-year period in which 30-day all-cause mortality was 16%.•There was no significant variability in 30-day mortality over our 9-year study period.•Our study showed that age, cancer, heart disease, neurologic disease, nursing home residence and Charlson score >3 are risk factors for 30-day mortality in patients with MRSA BSI.•Diabetes, PVD and readmission because of infection have statistically significant protective effects on 30-day mortality

SummaryObjectivesMethicillin-resistant Staphylococcus aureus (MRSA) blood stream infections (BSI) are a major health care problem accounting for a large percentage of nosocomial infections. The aim of this study was to identify risk factors associated with 30-day mortality in patients with MRSA BSI.MethodsThis was a retrospective study performed in Southeast Michigan. Over a 9- year period, a total of 1,168 patients were identified with MRSA BSI. Patient demographics and clinical data were retrieved and evaluated using electronic medical health records.Results30-day mortality during the 9-year study period was 16%. Significant risk factors for 30-day mortality were age, cancer, heart disease, neurologic disease, nursing home residence and Charlson score >3 with Odds Ratio (OR) of 1.03 (CI 1.02-1.04), 2.29 (CI 1.40-3.75), 1.78 (CI 1.20-2.63), 1.65 (CI 1.08-2.25), 1.66 (CI 1.02 − 2.70) and 1.86 (CI 1.18 − 2.95) correspondingly. Diabetes mellitus, peripheral vascular disease (PVD), and readmission were protective factors for 30-day mortality with OR of 0.53 (CI 0.36-0.78), 0.46 (CI 0.26-0.84) and 0.13 (CI0.05 − 0.32) respectively.ConclusionsOur study identified significant risk factors for 30-day mortality in patients with MRSA BSI. Interestingly, diabetes mellitus, PVD and readmission were protective effects on 30-day mortality. There was no statistically significant variability in 30-day mortality over the 9-year study period.