Fractures' associated mortality risk in orthogeriatric inpatients: a prospective 2-year survey

The most common osteoporotic fragility fractures are hip, vertebral and upper extremity fractures. An association with increased mortality is widely described with their occurrence. Fracture-specific associated death rates were determined in a 2-year follow-up for patients treated on an orthogeriatric ward. These were compared amongst each other, examined for changes with age and their impact on the relative mortality risk in relation to the corresponding population.

We assessed all patients that were treated in the course of a year on an orthogeriatric ward and suffered from the following injuries: hip (HF), vertebral (VF) and upper extremity fractures (UEF). In a 2-year follow-up it was possible to determine the month of death in the case of the patient's decease. Pairwise comparisons of the three fracture type death rates were performed through Cox-Regression. We stratified the fracture-dependent absolute mortality and age-specific mortality risk (ASMR) for age groups 71-80, 81-90 and 91-95.

Overall, we assessed 240 patients with HF, 96 with VF and 127 with UEF over the span of a year. 1- and 2-year-mortality was: HF: 29.6% a.e. 42.9%, VF: 29.2% a.e. 36.5%, UEF: 20.5% a.e 34.6%. Pairwise comparisons of these mortality values revealed no significant differences. In association with HF and VF, we observed a significant increase of 2-year mortality for the oldest compared to the youngest patients (HF: 60.4% vs. 22.5%; p = 0.028) (VF 70% vs. 14.3%; p = 0.033). The analogue comparison for UEF revealed no relevant difference in age-dependent mortality (40.9% vs. 31.1%; p = 0.784). Common for all fracture types ASMR's were more elevated in the younger patients and decreased with higher age.

The fracture-related mortality in the 2-year follow-up was comparable. We observed a reduction of relative mortality risk in the oldest patients. While a direct influence of fracture on mortality must be supposed, we support the thesis of the fracture rather being an indicator of higher susceptibility of timely death.