Surgical-site infection due to Staphylococcus aureus among elderly patients:: Mortality, duration of hospitalization, and cost

OBJECTIVES: To examine the impact of surgical-site infection (SSI) due to Staphylococcus aureus on mortality, duration of hospitalization, and hospital charges among elderly surgical patients and the impact of older age on these outcomes by comparing older and younger patients with S. aureus SSI. DESIGN: A nested cohort study. SETTING: A 750-bed, tertiary-care hospital and a 350-bed community hospital. PATIENTS: Ninety-six elderly patients (70 years and older) with S. aureus SSI were compared with 2 reference groups: 59 uninfected elderly patients and 131 younger patients with S. aureus SSI. RESULTS: Compared with uninfected elderly patients, elderly patients with S. aureus SSI were at risk for increased mortality (odds ratio [OR], 5.4; 95% confidence interval [CI95], 1.5-20.1), postoperative hospital-days (2.5-fold increase; CI95 2.0-3.1), and hospital charges (2.0-fold increase; CI95, 1.7-2.4; $41,117 mean attributable charges per SSI). Compared with younger patients with S. aureus SSI, elderly patients had increased mortality (adjusted OR, 2.9; CI95, 1.1-7.6), hospital-days (9 vs 13 days; P = .001), and median hospital charges ($45,767 vs $85,648; P < .001). CONCLUSIONS: Among elderly surgical patients, S. aureus SSI was independently associated with increased mortality, hospital-days, and cost. In addition, being at least 70 years old was a predictor of death in patients with S. aureus SSI (Infect Control Hosp Epidemiol 2004;25:461-467).