Abstract
BACKGROUND
Staphylococcus aureus bacteremia (SAB) disproportionately affects Black patients. The reasons for this disparity are unclear.
METHODS
We evaluated a prospectively ascertained cohort of patients with SAB from 1995 to 2020. Clinical characteristics, bacterial genotypes, and outcome were compared among Black and White patients with SAB. Multivariable logistic regression models were used to determine factor s independently associated with the outcomes.
RESULTS
Among 3068 patients with SAB, 1107 (36%) were Black. Black patients were younger (Median: 56 years vs. 63 years; p < 0.001), had higher rates of diabetes (47.5% vs. 34.5%; p < 0.001), hemodialysis dependence (40.0% vs. 7.3%; p < 0.001), and HIV (6.4% vs. 0.6%; p < 0.001). Black patients had higher rates of methicillin-resistant
S. aureus (49.3% vs 44.9%; p = 0.020), including the USA300 hypervirulent clone (11.5% vs. 8.4%; p = 0.007). White patients had higher rates of corticosteroid use (22.4% vs. 15.8%; p < 0.0001), and surgery in the preceding 30 days (28.1% vs. 18.7%; p < 0.001). Although median Acute Physiology Score (APS) at the time of initial SAB diagnosis was significantly higher in Black patients (Median APS 9, Interquartile Range [IQR] 5-14; vs. Median APS 7, IQR: 4-12; p < 0.001), race was not associated with 90-d ay mortality (risk ratio (RR): 1.02; 95% CI: 0.93–1.12, and rates of metastatic infection were lower among Black patients (37.2% vs. 41.3% White; p = 0.029).
CONCLUSIONS
Despite differences in Black patients' higher APS on presentation and more risk factors, including a 5 times higher risk of hemodialysis dependence, 90-day mortality among Black and White patients with SAB was similar.
