Hospital-acquired pneumonia: Attributable mortality and morbidity

A total of 1,001 consecutIve episodes of nosocomlal pneumonia in 901 patients was identified by routine surveillance at the University of Virginia Medical Center between 1979 and 1983 (8.6 episodes/1,000 admissions). When only initial episodes were examined, 890 patients comprised the study sample. The overall case fatality rate was 30%. Stepwlse logistic regression Indicated that time from admission to pneumonia (p = 0.0006), age (p <0.0001), prior use of mechanical ventilation (p = 0.0032), and neoplastic disease (p = 0.0062) were associated with mortality. Multiple regression analysis indicated that the factors associated with increased length of hospitalization included posttracheostomy status (p = 0.0001), prior mechanical ventilation (p = 0.0001), immunosuppressive or leuko penic status (p = 0.0009), nasogastric intubation (p = 0.0003), and prior bacte remia (p = 0.0 127). A sampled, individually matched cohort study (n = 74 pairs) was conducted to determine the proportion of mortality in cases that was attributable to infections (33%) and to determine excess hospital stay (seven days) among the patients with nosocomial pneumonia. Excess stay was statisti cally significant (p < 0.0001), but proportional mortality was only marginally significant (p = 0.0892). Our findings suggest that nosocomial pneumonia ac counts for approximately 33% of the crude mortality and contributes significantly to the economic burden associated with prolonged hospitalization.