title: Bone-muscle indices as risk factors for fractures in men: the Osteoporotic Fractures in Men (MrOS) Study.
abstract: OBJECTIVE
  To assess bone-muscle (B-M) indices as risk factors for incident fractures in men.
  
  
  METHODS
  Participants of the Osteoporotic Fractures in Men (MrOS) Study completed a peripheral quantitative computed tomography scan at 66% of their tibial length. Bone macrostructure, estimates of bone strength, and muscle area were computed. Areal bone mineral density (aBMD) and body composition were assessed with dual-energy X-ray absorptiometry. Four year incident non-spine and clinical vertebral fractures were ascertained. B-M indices were expressed as bone-to-muscle ratios for: strength, mass and area. Discriminative power and hazards ratios (HR) for fractures were reported.
  
  
  RESULTS
  In 1163 men (age: 77.2±5.2 years, body mass index (BMI): 28.0±4.0 kg/m(2), 4.1±0.9 follow-up years, 7.7% of men ⋝1 fracture), B-M indices were smaller in fractured men except for bending and areal indices. Smaller B-M indices were associated with increased fracture risk (HR: 1.30 to 1.74) independent of age and BMI. Strength and mass indices remained significant after accounting for lumbar spine but not total hip aBMD. However, aBMD correlated significantly with B-M indices.
  
  
  CONCLUSIONS
  Mass and bending B-M indices are risk factors for fractures in men, but may not improve fracture risk prediction beyond that provided by total hip aBMD.
authors.affiliation: Department of Medicine, McMaster University, Hamilton, ON, Canada.
authors.forename: A K O
authors.initials: AK
authors.lastname: Wong
authors.forename: P M
authors.initials: PM
authors.lastname: Cawthon
authors.forename: K W
authors.initials: KW
authors.lastname: Peters
authors.forename: S R
authors.initials: SR
authors.lastname: Cummings
authors.forename: C L
authors.initials: CL
authors.lastname: Gordon
authors.forename: Y
authors.initials: Y
authors.lastname: Sheu
authors.forename: K
authors.initials: K
authors.lastname: Ensrud
authors.forename: M
authors.initials: M
authors.lastname: Petit
authors.forename: J M
authors.initials: JM
authors.lastname: Zmuda
authors.forename: E
authors.initials: E
authors.lastname: Orwoll
authors.forename: J
authors.initials: J
authors.lastname: Cauley
mesh_terms: D015502:Absorptiometry, Photon; D000368:Aged; D000369:Aged, 80 and over; D001823:Body Composition; D015519:Bone Density; D001842:Bone and Bones / Q000473:pathology*; D018737:Hand Strength; D006801:Humans; D008297:Male; D018482:Muscle, Skeletal / Q000473:pathology*; D058866:Osteoporotic Fractures / Q000453:epidemiology / Q000473:pathology*; D012307:Risk Factors