Impact of nosocomial infection on length of stay and functional improvement among patients admitted to an acute rehabilitation unit

OBJECTIVE: To identify factors predictive of length of stay (LOS) and the l evel of functional improvement achieved among patients admitted to an acute rehabilitation unit for the first time, with special reference to the role of nosocomial infection. SETTING: A 40-bed acute rehabilitation unit within a 300-bed, tertiary-care , public, university-affiliated hospital. STUDY POPULATION: All patients admitted to the unit between January 1997 an d July 1998. DESIGN: Prospective cohort study in which demographic and clinical data, in cluding occurrence of nosocomial infection, were collected during the entir e unit admission of each patient. Multivariate linear regression analysis w as used to identify factors predictive of unit LOS or improvement in functi onal status as measured by the change in the Functional Independence Measur e (FIM) score between admission and discharge (Delta FIM). RESULTS: There were 423 admissions to the rehabilitation unit during the st udy period, of which 91 (21.5%) had spinal cord injury (SCI) as a principal diagnosis. One hundred seven nosocomial infections occurred during 84 (19. 9%) of the 423 admissions. The most common infections were urinary tract (3 1.8% of all infections), surgical-site (18.5%), and Clostridium difficile d iarrhea (15%). Only one patient died of infection. After controlling for se verity of illness on admission, functional status on admission, age, and ot her clinical factors, the significant positive predictors of unit LOS were as follows: SCI (P < .001), pressure ulcer (.002), and nosocomial infection (< .001). Significant negative predictors of Delta FIM were age (P < .001) , FIM score on admission (< .001), prior hospital LOS (.002), and nosocomia l infection (.007). CONCLUSIONS: Several variables were identified as contributing to a longer LOS or to a smaller improvement in functional status among patients admitte d for the first time to an acute rehabilitation unit. Of these variables, o nly nosocomial infection has the potential for modification. Studies of new approaches to prevent infections among patients undergoing acute rehabilit ation should be pursued (Infect Control Hosp Epidemiol 2001;22:83-87).