Indoor falls and number of previous falls are independent risk factors for long-term mortality after a hip fracture

Abstract

Background: Hip fractures are almost always the result of a fall. Causes and circumstances of falls may differ between frail and vigorous patients.

Aim: To describe the circumstances of falls causing hip fractures, number of falls during the previous year, and their association with long-term mortality.

Patients and methods: The study is a retrospective review conducted in a tertiary university hospital serving a population of 425,000 inhabitants in Barcelona. All patients admitted with hip fractures with medical records describing the circumstances and number of previous falls were included. The number of falls in the previous 12 months was recorded, including the one causing the fracture. The circumstances of the index fall were dichotomized according to whether it was from the patient's own height or above; day or night; indoors or outdoors, due to intrinsic or extrinsic causes. Cumulative mortality was recorded for almost 5 years after hip fracture.

Results: Indoor falls were strongly associated with shorter survival. Falling more than once in the previous year was also a risk factor for long-term mortality (hazard ratio 1.461, p < 0.001 and hazard ratio 1.035, p = 0.008 respectively).

Conclusion: Indoor falls and falling more than once in the previous year are long-term risk factors for mortality after hip fractures. It is always essential to take a careful patient history on admission to determine the number of falls and their circumstances, and special care should be taken to reduce mortality in patients at high risk.

Keywords: Falls; Hip fracture; Mortality.

Fig. 1

Kaplan–Meier curves for cumulative survival after hip fracture. a Cumulative survival in relation to all parameters. b Cumulative survival in relation to an indoor/outdoor index fall. c Cumulative survival in relation to more than one fall in the previous 12 months, including the index fall