Community-acquired bacteremia at a teaching versus a nonteaching hospital:Impact of acute severity of illness on 30-day mortality

Background: Few studies have focused recently on the epidemiology of commun ity-acquired bacteremia (CAB) and there have been few comparisons of CAB in teaching versus nonteaching hospitals. Objectives: To compare the clinical characteristics, acute severity of illn ess, and 30-day mortality of patients with CAB admitted to a teaching and a nonteaching hospital and to define predictors of 30-day mortality among pa tients with CAB that would be identifiable at the time of admission to the hospital. Methods: This was a retrospective study of CAB at a reaching hospital (n = 174 episodes) compared to a community nonteaching hospital (n = 74 episodes ) during 1995. Data collected included demographic characteristics, underly ing diseases, sources of CAB, and antimicrobial therapy. Acute severity of illness on admission was measured by using the acute physiology score compo nent of the Acute Physiology and Chronic Health Evaluation III system (APS APACHE III). Main Outcome Measure: Status, dead or alive, 30 days after admission for CA B. Results: At the nonteaching hospital, patients were older but, on average, significantly less acutely ill las measured by the admission APS APACHE III score) than were those at the teaching hospital. In contrast, patients wit h HN infection, posttransplantation, or on hemodialysis were identified onl y at the teaching hospital. Overall, organisms causing CAB at both hospital s were similar except that Staphylococcus aureus CAB occurred significantly more often at the teaching hospital and Escherichia coli CAB occurred more often at the nonteaching hospital. There was no significant difference in 30-day mortality in patients with CAB between the teaching hospital (19.3%) and the nonteaching hospital (16.7%; P =.63). APS APACHE III score on admi ssion identified episodes of CAB with a low- and a high-risk for 30-day mor tality at both hospitals. Independent predictors of 30-day mortality were A PACHE III score on admission (P < .001) and pneumonia as a source of CAB (P = .012). Conclusions: Among patients with CAB, acute severity of illness on admissio n was the most important predictor of 30-day mortality at both hospitals. E ven though patients with CAB were, on average, more severely ill at the tim e of admission to the teaching hospital, 30-day mortality rates were not si gnificantly different between the two hospitals because deaths correlated w ith high APS APACHE III scores at both facilities. The APS APACHE LII score on admission provides important prognostic information among patients with CAB.