Abstract
OBJECTIVES: To quantify the effect of nosocomial bloodstream infection (BSI) on older adults, including mortality, length of stay (LOS), and costs attributed to BSI. DESIGN: Retrospective cohort study. SETTING: Eight acute care hospitals (7 community hospitals and 1 tertiary university-affiliated facility) belonging to the Duke Infection Control Outreach Network (DICON) from the states of North Carolina and Virginia. PARTICIPANTS: Elderly patients over 65 years of age. MEASUREMENTS: A multistate, multicenter, matched, retrospective cohort study was conducted from January 1994 through June 2002 in eight hospitals from the Southern-Central United States. Patients aged >65 years with nosocomial BSI were enrolled. Controls without bloodstream infection were matched to cases. Outcomes during the 90-day period following hospital discharge were evaluated to determine the association between BSI and mortality, hospital costs, and LOS. RESULTS: Eight-hundred thirty cases and 830 matched controls were identified, all with a mean age of 74.4 years. Among cases, 81% of BSIs were central line-associated and Staphylococcus aureus was the most common pathogen accounting for 34.6% of infections (2/3 were methicillin resistant). The mortality rate of cases was 49.4%, compared to 33.2% for controls (OR = 2.1, P < .001), LOS was 29.2 days for cases and 20.2 days for controls (P < .001), and hospital charges were $102,276 for cases compared to $69,690 for controls (P < .001). The mean LOS and mean costs attributable to BSI were 10 days and $43,208, respectively. CONCLUSION: Nosocomial BSI in older adults was significantly associated with increases in 90-day mortality, increased LOS, and increased costs of care. Preventive interventions to eliminate nosocomial BSIs in older adults would likely be cost effective.