Effect of comorbidity on relative survival following hospitalisation for fall-related hip fracture in older people

Aim: To assess the effect of comorbidity on relative survival after hip fracture. Methods: Relative survival analysis was undertaken in 16 838 fall-related hip fracture hospitalisations in New South Wales, Australia. Comorbidity was measured on the basis of additional diagnosis codes on the same hospital separation as the hip fracture using the Charlson Comorbidity Index (CCI). Interval-specific relative survival and relative excess risk of death were calculated. Results: Comorbidity was more frequently documented in men than women across the age groups. Survival decreased with increasing age and increasing comorbidity, but the relative impact of comorbidity was greater in the younger-old age group (65-74 years). The excess mortality in men was not accounted for by age or comorbidities. Conclusions: This study demonstrates an association between increasing comorbidity and death particularly in the first 3 months post hip fracture. It also highlights a relative excess risk of death in men after hip fracture after adjusting for age and comorbidity.