title: Hip fractures and femoral bone mineral density in male former elite athletes.
abstract: BACKGROUND
  We studied whether vigorous physical activity in young adulthood is associated with higher femoral bone density and lower risk of hip fracture at older age in men.
  
  
  METHODS
  A cohort of former male elite athletes (n=2147) and matched control subjects (n=1467) were studied for their leisure physical activity, and for fragility fractures at the hip (proximal femur) by Cox regression. Areal bone mineral densities (aBMD) at femoral neck and trochanter region were measured using dual-energy X-ray absorptiometry in a subgroup of the former athletes (n=87; median age 59 years) and in a population-based control group (n=194) and compared by general linear models.
  
  
  RESULTS
  After their active sporting careers, the former athletes participated in leisure physical activity more than the matched control subjects (p<0.0001). The hazard ratio (HR) of osteoporotic hip fracture adjusted for the occupational group was 0.77 (95% CI 0.45 to 1.32, p=0.34) in the athletes compared with the control subjects. The mean age at the time of the fracture event was 76.9 years (95% CI 73.2 to 78.8) for the athletes and 70.6 years (95% CI 67.1 to 72.9) for the matched control subjects (p=0.005). Adjusted for age and body mass index, aBMD at the proximal femur was significantly higher in the former athletes compared with the population-based control group (p<0.0001 for both measurement sites).
  
  
  CONCLUSIONS
  Osteoporotic hip fractures were sustained at a significantly older age among former athletes compared with control subjects. Clear skeletal benefits of long-term physical loading were also observed in comparative DXA measurements of aBMD.
authors.affiliation: The ORTON Orthopaedic Hospital, ORTON Foundation, Tenholantie 10, FIN-00280 Helsinki, Finland. jyrki.kettunen@orton.fi
authors.forename: Jyrki A
authors.initials: JA
authors.lastname: Kettunen
authors.forename: Olli
authors.initials: O
authors.lastname: Impivaara
authors.forename: Urho M
authors.initials: UM
authors.lastname: Kujala
authors.forename: Miika
authors.initials: M
authors.lastname: Linna
authors.forename: Juhani
authors.initials: J
authors.lastname: Mäki
authors.forename: Heli
authors.initials: H
authors.lastname: Räty
authors.forename: Erkki
authors.initials: E
authors.lastname: Alanen
authors.forename: Jaakko
authors.initials: J
authors.lastname: Kaprio
authors.forename: Tapio
authors.initials: T
authors.lastname: Videman
authors.forename: Seppo
authors.initials: S
authors.lastname: Sarna
mesh_terms: D056352:Athletes; D015992:Body Mass Index; D015519:Bone Density / Q000502:physiology*; D016022:Case-Control Studies; D005269:Femur / Q000503:physiopathology*; D005272:Femur Neck / Q000503:physiopathology; D006620:Hip Fractures / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D011795:Surveys and Questionnaires