FALL-RELATED FACTORS AND RISK OF HIP FRACTURE - THE EPIDOS PROSPECTIVE-STUDY

Background Most hip fractures result from falls. However, the role of fall-related factors has seldom been examined. Comparison of the predi ctive value of these factors with that of bone mineral density (BMD) h as important implications for the prevention of hip fractures. Methods We assessed femoral-neck BMD by dual-photon X-ray absorptiometry and potential fall-related risk factors, which included self-reported phys ical capacity, neuromuscular function, mobility, visual function, and use of medication in 7575 women, aged 75 years or older, with no histo ry of hip fracture recruited at five centres in France. We followed up these women every 4 months to record incident hip fractures. During a n average of 1.9 years of follow-up, 154 women suffered a first hip fr acture. Findings In age-adjusted multivariate analyses, we found four independent fall-related predictors of hip fracture: slower gait speed (relative risk=1.4 for 1 SD decrease [95% CI 1.1-1.6]); difficulty in doing a tandem (heel-to-toe) walk (1.2 for 1 point on the difficulty score [1.0-1.5]); reduced visual acuity (20 for acuity less than or eq ual to 2/10 [1.1-3.7]); and small calf circumference (1.5 [1.0-2.2]). After adjustment for femoral-neck BMD, neuromuscular impairment-gait s peed, tandem walk-and poor vision remained significantly associated wi th an increased risk of subsequent hip fracture. With high risk define d as the top quartile of risk, the rate of hip fracture among women cl assified as high risk based on both a high fall-risk status and low BM D was 29 per 1000 woman-years, compared with 11 per 1000 for women cla ssified as high risk by either a high fall-risk status or low BMD; for women classified as low risk based on both criteria the rate was five per 1000. Interpretation We conclude that neuromuscular and visual im pairments, as well as femoral-neck BMD, are significant and independen t predictors of the risk of hip fracture in elderly mobile women, and that their combined assessment improves the prediction of hip fracture s.