Post-operative degree of mobilization at two weeks predicts one-year mortality after hip fracture

Although several investigations have tested physical activity a few months or one year after hip fracture, only a few have assessed physical activity shortly after hip fracture. The aim of this study was to evaluate how physical function two weeks after hip fracture operation predicts 12-month mortality. This was a prospective study of hip fracture patients with one-year follow-up, carried out in Jyväskylä Central Hospital in Finland.

In this study, there were 243 consecutive community-dwelling patients aged 65 or older, who were able to walk before hip fracture. Two weeks after operation, information was gathered on pre-fracture activities of daily living (ADLs) and instrumental activities of daily living (IADLs). Patients' ability to stand up, sit down and walk was assessed. The follow-up lasted 12 months.

The best predictor for mortality after one year was inability to stand up, hazard ratio (HR) 4.64 (95% CI 2.11-10.18, p < 0.001). The corresponding HRs concerning inability to sit down were 4.52 (95% CI 2.10-9.72, p < 0.001), inability to walk 2.39 (95% CI 1.20-4.78, p = 0.013), ADL score 1.43 (95% CI 1.16-1.76, p = 0.001) and IADL score 1.19 (95% CI 1.03-1.38, p = 0.017). These variables were age- and sex-adjusted. According to the multiple proportional hazard model there was only one variable with statistical significance, i.e., the pre-fracture ADL-score (p = 0.025).

Inability to stand up, sit down or walk two weeks after operation were the strongest predictors for mortality among operated hip fracture patients. We suggest that focus should be directed to verify if better survival might be achieved by more intensive rehabilitation immediately after the operation. The pre-fracture ADL-score appeared to be the only variable reaching statistical significance in the multiple proportional hazard model. This fact may reflect frailty and affect decisions concerning the rehabilitation program.