Total hospital stay for hip fracture: measuring the variations due to pre-fracture residence, rehabilitation, complications and comorbidities

BACKGROUND: Hospital treatment for hip fracture is complex, often involving sequential episodes for acute orthopaedics, rehabilitation and care of contingent conditions. Most reports of hospital length of stay (LOS) address only the acute phase of care. This study identifies the frequency and mean duration of the component episodes within total hospital stay, and measures the impacts of patient-level and clinical service variables upon both acute phase and total LOS. METHODS: Administrative datasets for 2552 subjects hospitalised between 1 July 2008 and 30 June 2009 were linked. Associations between LOS, pre-fracture accommodation status, age, sex, fracture type, hospital separation codes, selected comorbidities and complications were examined in regression models for acute phase and total LOS for patients from residential aged care (RAC) and from the community. RESULTS: Mean total LOS was 30.8 days, with 43 per cent attributable to acute fracture management, 37 per cent to rehabilitation and 20 per cent to management of contingent conditions. Community patients had unadjusted total LOS of 35.4 days compared with 18.8 days for RAC patients (p <0.001). The proportion of transfers into rehabilitation (57 per cent vs 17 per cent, p <0.001) was the major determinant for this difference. In multivariate analyses, new RAC placement, discharge to other facilities, and complications of pressure ulcer, urinary or surgical site infections increased LOS by at least four days in one or more phases of hospital stay. CONCLUSION: Pre-fracture residence, selection for rehabilitation, discharge destination and specific complications are key determinants for acute phase and total LOS. Calculating the dimensions of specific determinants for LOS may identify potential efficiencies from targeted interventions such as orthogeriatric care models.