Factors predicting rehabilitation outcomes of elderly patients with hip fracture.

OBJECTIVE To identify predictors of rehabilitation outcomes for the development of a case-mix system to rehabilitate patients suffering from hip fractures. DESIGN Prospective cohort study. SETTING Two hospitals in Hong Kong. PATIENTS A cohort of hip fracture patients in 2005 (n=303) with a mean age of 82 years was studied. Rehabilitation outcomes were defined as: mortality, length of stay, placement, ambulation status, activity of daily living at the time of discharge and at 6-month follow-up. A comparison between groups and multivariate analysis was conducted to validate the best predictors. MAIN OUTCOME MEASURES Potential predictors and rehabilitation outcomes. RESULTS Two predictors, the Abbreviated Mental Test score of lower than 6 (odds ratio=0.19, P<0.05) and the Functional Independence Measures score of lower than 75 (odds ratio=38.0, P<0.05), at the time of admission to the rehabilitation setting were found to be related to outcomes. Our findings provided further support for a case-mix system based on these two factors, as they could correctly assign patients into three groups with different baseline characteristics and outcomes. A review of the possible limitations of the existing service with respect to each case-mix group was also conducted. CONCLUSION A case-mix system utilising the cognition and activity of daily living function is recommended. Revisions of respective care plans are advocated with more realistic outcome expectations and specific actions for the respective case-mix groups. An evaluation study on the usefulness of this case-mix classification could then follow.