Evaluating the Impact of Socioeconomic Status on Clinical Presentation in Patients with Staphylococcus aureus Bacteremia
Methods: This was a prospective cohort study of all adult patients with a first presentation of SAB presenting to San Francisco General Hospital, the San Francisco County hospital, from 2008-2012. Subjects were identified by a comprehensive infection control surveillance system. Primary predictors were homelessness, percent of individuals under the federal poverty limit (POV) or median household income (MHI) within each patient’s reported zip code. Primary outcomes were intensive care unit (ICU) admission, meeting systemic inflammatory response syndrome (SIRS) criteria on admission, and diagnosis of vertebral osteomyelitis or endocarditis. Multivariate logistic regression controlling for HIV status, age, race, gender, injection drug use and the Charlson comorbidity index was used to assess the impact of SES on primary outcomes.
Results: There were 437 unique individuals with first presentations of SAB, of which 406 had homelessness data and 398 had a reported zip code, median income and poverty data. 94 (23.2%) of individuals were homeless. In separate logistic regression models, MHI and POV were not associated with ICU admission, but homelessness was protective against admission to the ICU (OR 0.39, 95% CI (0.19, 0.80)). No variables were predictive of meeting SIRS criteria on admission. MHI, POV and homelessness were not associated with diagnoses of vertebral osteomyelitis/discitis or endocarditis. Post-hoc Cox proportional hazard modeling revealed no association between homelessness and mortality, readmission or SAB recurrence at 90 days.
Conclusion: In an ethnically and economically diverse safety-net population, in patients presenting with SAB, lower neighborhood SES was not associated with complications at presentation including endocarditis, vertebral osteomyelitis/discitis, ICU admission and meeting SIRS criteria. Homelessness was protective against ICU admission, suggesting SES may impact triage decision-making.
A. Gahbauer, None
B. Imp, None
D. Deck, Forest Pharmaceuticals: speaker, Speaker honorarium
Merck: speaker, Speaker honorarium
S. Doernberg, None
H. Chambers, None