title: Bone geometry and strength are adapted to muscle force in children and adolescents perinatally infected with HIV.
abstract: OBJECTIVE
  To determine if bone health is compromised in perinatally HIV-infected youth.
  
  
  METHODS
  We assessed BMC at the proximal femur, lumbar spine and total body using DXA in perinatally HIV-infected youth (n=31; 9-18y). Using pQCT, we assessed muscle CSA, total and cortical bone area, cortical BMD and thickness and strength strain index at the tibial shaft. Thirty and 18 participants returned at 12- and 24-months, respectively. We calculated age- and sex-specific z-scores for the HIV-infected youth using data from a healthy cohort (n=883; 9-18y).
  
  
  RESULTS
  At baseline, height and MCSA were reduced in HIV-infected youth (-0.79 to -0.23, p<0.05). BMC z-scores adjusted for height and lean mass were lower than controls at all sites except the lumbar spine (-0.57 to -0.27, p<0.05). Bone area and strength z-scores were not different from zero after adjusting for tibial length and MCSA. In contrast, cortical BMD z-scores were greater in HIV-infected youth (0.46, p=0.011). Z-scores for all bone outcomes showed positive trends over time in HIV-infected youth.
  
  
  CONCLUSIONS
  Although HIV infection may be associated with bone mass deficits during growth, bone geometry and strength appear adapted to muscle force. Further, deficits in bone mass may dissipate over time in this population.
authors: Department of Orthopaedics, University of British Columbia, Vancouver, Canada. heather.macdonald@ubc.ca
authors: H M
authors: HM
authors: Macdonald
authors: J
authors: J
authors: Chu
authors: L
authors: L
authors: Nettlefold
authors: E J
authors: EJ
authors: Maan
authors: J C
authors: JC
authors: Forbes
authors: H
authors: H
authors: Côté
authors: A
authors: A
authors: Alimenti
mesh_terms: D015502:Absorptiometry, Photon / Q000379:methods; D000222:Adaptation, Physiological / Q000502:physiology*; D000293:Adolescent; D015519:Bone Density / Q000502:physiology*; D002648:Child; D015331:Cohort Studies; D019245:Compressive Strength / Q000502:physiology; D005260:Female; D005500:Follow-Up Studies; D015658:HIV Infections / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000000981:diagnostic imaging* / Q000453:epidemiology*