The cause of increased mortality following proximal non-hip fractures is unknown. We sought to determine post-fracture trajectories of subsequent hospital admissions and mortality to develop an understanding of why patients with non-hip fractures die prematurely.
This nationwide Danish population-based study included all individuals aged 50+ years who sustained an incident fragility fracture 2001-2014. Fracture patients were matched 1:4 by sex, age and comorbidity status with non-fracture subjects alive at fracture time. Morbidities included 33 unique conditions of the Charlson or Elixhauser index. We modelled the contribution of specific fractures on risk of subsequent admissions or death within the following 2 years. These models are visualised for 2 representative proximal and distal fracture types, humers and hand, respectively (Figure).
There were 95,372 men with fracture (age at fracture: 72± 11) and 212,498 women (75± 11) followed by 19,519 and 30,677 deaths, respectively. The trajectories to admissions and mortality following individual proximal fractures (e.g. humerus, vertebrae, rib, femur) differed from distal fractures (hand, forearm, foot). Proximal, but not distal fracture subjects had greater risk of any admission within 2 years compared with their non-fracture counterparts. Humerus fractures, with or without major comorbidities, were more likely (red bands in Figure) to be admitted for any major hospitalisation than their non-fracture counterparts. Moreover, there was an increased mortality risk for humerus fractures with or without major hospitalisation. By contrast, there was a similar risk (gray bands) of hospital admissions between hand fractures and controls. Indeed mortality risk was reduced (blue bands) for hand fractures compared with non-fracture controls.
This study has demonstrated a novel trajectory of increased major hospitalisations post proximal but not distal fracture that contributes to this increased mortality. These findings give an insight as to why proximal fracture subjects may die prematurely that could lead to specific avenues for intervention.