Mortality after low-energy fractures in patients aged at least 45 years old.

BACKGROUND

Fractures sustained in low-energy injuries are recognized as a major public health issue, although, with the exception of proximal femoral fractures, little is known about the subsequent mortality rates. The aim of this study was to compare the survival rates of a population of individuals who sustained 3 types of low-energy fractures with age-matched cohorts from within the same population.

METHODS

Between January 1988 and December 1999, data were prospectively gathered from all inpatient and outpatient fracture cases at a single trauma unit. During this time, 18,019 patients sustained low-energy fractures of the proximal femur, proximal humerus, or wrist. Survival analysis using the life table method was performed and hazard ratios calculated for risk of mortality when compared to general population controls within the first year postinjury, between the second and fifth years postinjury, and between the sixth and tenth years postinjury. The effects of various social, physical, and mental health parameters on survival were also analyzed using a Cox proportional hazards model.

RESULTS

The patients who sustained proximal femoral fractures were older and significantly more physically and mentally impaired than the patients who sustained wrist fractures. The demographic features of the proximal humeral fracture cohort were intermediate between these 2 groups. The mortality was high in all age groups following proximal femoral and proximal humeral fractures, though the relative risk of death, when compared to age-matched population controls, decreased with increasing age at fracture. The risk of death in these groups was greatest in younger individuals and in the first year postinjury. The wrist fracture population had similar or enhanced survival when compared to age-matched population controls. The mortality after fracture was independently predicted by age at fracture, male gender, and use of walking aids, for all 3 fracture groups (P < 0.05), and additionally by level of social dependence in the proximal femoral fracture group (P < 0.05).

LEVEL OF EVIDENCE

level one, prospective cohort study.

CONCLUSIONS

There is prolonged risk of premature mortality seen in both proximal femoral and proximal humeral fracture groups in the younger age cohorts, possibly as a result of concomitant medical comorbidities contributing to their premature deaths. Elderly patients sustaining proximal femoral fractures, despite high risk of mortality in the first year after injury, have survival approaching those of the general population in the longer term. Elderly patients who sustain wrist fractures have consistently better survival rates than the general population. This group of patients may be physiologically more robust than their age-matched peers in the general population.