Risk Factors for Fracture Following a Fall Among Older People in Residential Care Facilities in Australia

Abstract

To investigate which factors best predict whether a fall will result in a fracture. Prospective cohort. Residential care facilities. One thousand three hundred forty-two older men and women (mean age 86.0) who had a fall. Clinical risk factors and bone fragility by calcaneus broadband ultrasound attenuation (BUA) were assessed at baseline, and falls and fall-related fractures were recorded for up to 2 years. All fractures were validated using X-ray reports. During a median follow-up of 1.97 years, 6,646 falls resulted in 308 fractures. Fracture rates were 6.7, 4.8, and 3.1 per 100 falls for BUA in the lowest (10.5-39.7 dB/MHz), middle (39.8-58.9 dB/MHz), and highest (>/=58.9dB/MHz) tertiles, respectively. In multivariate analysis, the odds ratio for any fracture was 1.17 (95% confidence interval=1.08-1.27; P<.001) for every 10-dB/MHz reduction in BUA. Other significant risk factors in the model were lower weight, longer leg length, better balance, no severe cognitive impairment, intermediate care residence, lack of a history of falls in the previous year, and a history of fracture since age 50. For hip fracture, the only significant risk factors were lower weight, longer leg length, intermediate care residence, and lack of falls history. Important risk factors for whether a fracture occurs immediately after a fall include direct measures of bone fragility and a number of anthropometric and clinical factors that may increase or attenuate the mechanical impact of a fall. By identifying those at highest risk of fracture after a fall, these findings should have important implications for fracture prevention strategies.