title: Impact of vitamin D, bisphosphonate, and combination therapy on bone mineral density in kidney transplant patients.
abstract: BACKGROUND
  Osteoporosis can develop and become aggravated in kidney transplant patients; however, the best preventive options for post-transplantation osteoporosis remain controversial.
  
  
  METHODS
  We retrospectively analyzed cohort of 182 renal transplant recipients of mean age 46.7 ± 12.1 years including 47.3% women. Seventy-three patients received neither vitamin D nor bisphosphonate after transplantation (group 1). The other patients were classified into the following 3 groups: calcium plus vitamin D (group 2; n = 40); bisphosphonate (group 3; n = 18); and both regimens (group 4; n = 51). Bone mineral density (BMD) was evaluated by dual-energy X-ray absorptiometry at baseline and at 1 year after transplantation.
  
  
  RESULTS
  At 1 year after transplantation, T-scores of the femoral neck and entire femur were significantly decreased in group 1 (-0.23 ± 0.65 [P = .004] and -0.21 ± 0.74 [P = .018], respectively), whereas the lumbar spine was significantly increased in group 4 (0.27 ± 0.79; P = .020). Post hoc analysis demonstrated that the delta T-score was significantly lower in group 1 than in group 4 (P = .009, 0.035, and 0.031 for lumbar spine, femoral neck, and entire femur, respectively). In a multivariate analysis adjusted by age, sex, body mass index, dialysis duration, diabetes, calcineurin inhibitors, estimated glomerular filtration rate, and persistent hyperparathyroidism, both group 2 and group 4 showed protective effects on BMD reduction (odds ratio [OR], 0.165; 95% confidence interval [CI] 0.032-0.845 [P = .031]; and OR, 0.169; 95% CI, 0.045-0.626 [P = .008]; respectively). However, group 3 did not show a protective effect (OR, 0.777; 95% CI, 0.198-3.054; P = .718), because their incidence of persistent hyperparathyroidism after transplantation was significantly higher (50.0%) than the other groups (P < .001). The incidence of bone fractures did not differ among the groups.
  
  
  CONCLUSIONS
  Combination therapy with vitamin D and bisphosphonate was the most effective regimen to improve BMD among kidney recipients.
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: H J
authors.initials: HJ
authors.lastname: Jeon
authors.forename: M
authors.initials: M
authors.lastname: Han
authors.forename: J C
authors.initials: JC
authors.lastname: Jeong
authors.forename: Y J
authors.initials: YJ
authors.lastname: Kim
authors.forename: H Y
authors.initials: HY
authors.lastname: Kwon
authors.forename: T Y
authors.initials: TY
authors.lastname: Koo
authors.forename: C
authors.initials: C
authors.lastname: Ahn
authors.forename: J
authors.initials: J
authors.lastname: Yang
mesh_terms: D015502:Absorptiometry, Photon; D000328:Adult; D015519:Bone Density / Q000187:drug effects*; D004164:Diphosphonates / Q000008:administration & dosage / Q000494:pharmacology*; D005260:Female; D006801:Humans; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D014807:Vitamin D / Q000008:administration & dosage / Q000494:pharmacology*
chemical_list: D004164:Diphosphonates; D014807:Vitamin D