title: Gait speed and one-leg standing time each add to the predictive ability of FRAX.
abstract: Gait speed or one-leg standing time (OLST) as additional predictors in FRAX. Population 351 elderly women followed 10 years. Both could improve predictions. The area under curve (AUC) for FRAX is 0.59, OLST is 0.69 and gait speed is 0.71. The net reclassification index (NRI) for classification to highest risk quartile or lowest three quartiles was 0.24 for gait speed and non-significant for OLST.
  
  
  
  The risk of falls and bone strength are two main determinants of hip fracture risk. The fracture risk assessment tool FRAX, however, lacks direct measures of fall risk1. A short OLST and a slow gait speed are both fall-related risk factors for hip fractures. The aim of this study was to investigate whether the addition to FRAX of either gait speed or OLST could improve the predictive ability for hip fractures, compared to FRAX alone.
  
  
  
  A population-based sample of 351 women aged between 69 and 79 years were tested for one-leg standing time with eyes open and mean gait speed over a 15 + 15-m walk. Fracture and mortality data were obtained from health care registers.
  
  
  
  The AUC for the receiver operating characteristic (ROC) increased from 0.61 to 0.71 when gait speed was added to FRAX. The AUC was 0.69 for OLST added to FRAX. The highest quartile of hip fracture risks according to FRAX had an absolute 10-year risk of ≥15%. The population was divided into one group with a hip fracture risk of ≥15% and one group with a fracture risk of <15%. NRI for addition of gait speed to FRAX was 0.24 (p = 0.023), while NRI was 0.08 (p = 0.544) for addition of OLST to FRAX.
  
  
  
  Gait speed tended to improve the predictive ability of FRAX more than OLST, but they both added value to FRAX.
authors.affiliation: Division of Family Medicine, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Alfred Nobels allé 23, 14183 Huddinge, Stockholm, Sweden. hans.lundin@ki.se.
authors.forename: H
authors.identifier: 0000-0001-8840-3573
authors.initials: H
authors.lastname: Lundin
authors.affiliation: Department of Molecular Medicine and Surgery (MMK), Division of Endocrinology, Metabolism and Diabetes, Karolinska Institutet, 171 76, Stockholm, Sweden.
authors.forename: M
authors.initials: M
authors.lastname: Sääf
authors.affiliation: Division of Family Medicine, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Alfred Nobels allé 23, 14183 Huddinge, Stockholm, Sweden.
authors.forename: L-E
authors.initials: LE
authors.lastname: Strender
authors.affiliation: Department of Molecular Medicine and Surgery, Division of Diagnostic Radiology, Karolinska Institutet, 171 76, Stockholm, Sweden.
authors.forename: S
authors.initials: S
authors.lastname: Nyren
authors.affiliation: Division of Family Medicine, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Alfred Nobels allé 23, 14183 Huddinge, Stockholm, Sweden.
authors.forename: S-E
authors.initials: SE
authors.lastname: Johansson
authors.affiliation: Division of Family Medicine, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Alfred Nobels allé 23, 14183 Huddinge, Stockholm, Sweden.
authors.forename: H
authors.initials: H
authors.lastname: Salminen
mesh_terms: D000058:Accidental Falls / Q000706:statistics & numerical data; D000368:Aged; D015519:Bone Density / Q000502:physiology; D005260:Female; D005265:Femoral Neck Fractures / Q000453:epidemiology / Q000209:etiology / Q000503:physiopathology; D005500:Follow-Up Studies; D005684:Gait / Q000502:physiology*; D006305:Health Status Indicators; D006620:Hip Fractures / Q000453:epidemiology / Q000209:etiology* / Q000503:physiopathology; D006801:Humans; D058866:Osteoporotic Fractures / Q000453:epidemiology / Q000209:etiology* / Q000503:physiopathology; D004856:Postural Balance / Q000502:physiology*; D011237:Predictive Value of Tests; D011379:Prognosis; D018570:Risk Assessment / Q000379:methods; D012307:Risk Factors; D013548:Sweden / Q000453:epidemiology
keywords: femoral neck fractures; fracture risk assessment; gait; hip fractures; postural balance