title: Determinants of bone mineral density in stable kidney transplant recipients.
abstract: BACKGROUND
  Kidney transplant recipients (KTR) are at increased risk for bone loss. Determinants of bone mineral density (BMD) in an unselected KTR population have not previously been described.
  
  
  METHODS
  We conducted a cross-sectional analysis of 389 stable KTRs undergoing bone mineral densitometry assessment by dual-energy X-ray absorptiometry at the lumbar spine, total hip and femoral neck. Risk factors for osteopenia and osteoporosis were determined by t-tests or ANOVA and chi-square analysis as appropriate. Factors associated with reduced BMD were ascertained using multivariate linear regression.
  
  
  RESULTS
  At the lumbar spine, 247 demonstrated normal BMD, 115 had osteopenia and 27 osteoporosis. Corresponding prevalence rates for the total hip and femoral neck were 222/143/24 and 178/184/27, respectively. Osteopenia or osteoporosis was more prevalent at the femoral neck than lumbar spine (p=0.002). Osteopenia or osteoporosis at the spine, hip and femoral neck were highly correlated (p<0.0001). Independent associations with reduced BMD included female sex (p<0.0001) and lower body mass index (p<0.0001) at all sites, age for total hip and femoral neck (p=0.0001), and hyperparathyroidism (p=0.036), time posttransplant (p=0.0001) for the femoral neck, with no association by renal function or 25-OH vitamin D level at any site.
  
  
  CONCLUSIONS
  Significant bone loss in KTRs is most prevalent at the femoral neck. Identifying risk factors for specific sites may allow for earlier intervention prior to osteoporosis development.
authors.affiliation: Division of Nephrology, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Alok K
authors.initials: AK
authors.lastname: Gupta
authors.forename: Michael
authors.initials: M
authors.lastname: Huang
authors.forename: G V Ramesh
authors.initials: GV
authors.lastname: Prasad
mesh_terms: D015502:Absorptiometry, Photon; D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D015519:Bone Density; D001851:Bone Diseases, Metabolic / Q000097:blood / Q000000981:diagnostic imaging / Q000209:etiology* / Q000473:pathology; D003430:Cross-Sectional Studies; D005260:Female; D005272:Femur Neck / Q000378:metabolism / Q000473:pathology* / Q000503:physiopathology; D006621:Hip Joint / Q000378:metabolism / Q000473:pathology* / Q000503:physiopathology; D006801:Humans; D016030:Kidney Transplantation / Q000009:adverse effects*; D016014:Linear Models; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009864:Ontario; D010024:Osteoporosis / Q000097:blood / Q000000981:diagnostic imaging / Q000209:etiology* / Q000473:pathology; D015995:Prevalence; D018570:Risk Assessment; D012307:Risk Factors; D016896:Treatment Outcome
chemical_list: D015415:Biomarkers