BsmI vitamin D receptor genotypes influence the efficacy of antiresorptive treatments in postmenopausal osteoporotic women. A 1-year multicenter, randomized and controlled trial

Osteoporos Int. 2005 Aug;16(8):943-52. doi: 10.1007/s00198-004-1800-5. Epub 2005 Mar 1.

Abstract

Vitamin D receptor (VDR) gene polymorphisms could be considered one of the factors influencing the efficacy of the anti-osteoporotic treatments. In this multicenter, prospective, randomized and controlled trial we evaluated whether BsmI vitamin D receptor (VDR) genotypes influence the efficacy of antiresorptive treatment regimes (administered alone or in combination) in postmenopausal osteoporotic women. Using restriction endonuclease, we identified the BsmI VDR polymorphism in 1,100 postmenopausal women with osteoporosis. The women were randomized, taking account of genotype, into five treatment groups: (1) alendronate (Aln, 10 mg/day) plus raloxifene (Rlx, 60 mg/day); (2) Aln plus hormone replacement therapy (HRT, 0.625 mg/day conjugated equine estrogens plus 2.5 mg/day medroxyprogesterone acetate); (3) Aln alone; (4) HRT alone; and (5) Rlx alone. Lumbar-spine bone mineral density (BMD) and bone turnover markers were measured at study entry and after 1 year of treatment. Using the general linear model (GLM) repeated-measures procedure, the means of BMD and bone turnover markers significantly differed from baseline after a period of treatment. In particular, the mean change from baseline for BMD was -0.034 (95% confidence interval [CI]: -0.037 to -0.031, P <0.001); for serum osteocalcin (OC) it was 1.369 (95% CI: 1.289 to 1.448, P <0.001); and for urinary deoxypyridinoline (DPD) it was 1.322 (95% CI: 1.242 to 1.401, P <0.001), indicating a considerable variation before and after treatment of these indicators. In all three cases these effects appeared significantly influenced by treatments, genotypes, and the treatments*genotypes interaction term (P <0.001 each, except for the BMD and genotype effect with P =0.02), and not by the investigational centers involved in the study. In conclusion, in postmenopausal osteoporotic women, BsmI VDR genotypes influence the efficacy of antiresorptive drugs particularly when used in combination.

Publication types

  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Oral
  • Aged
  • Alendronate / administration & dosage
  • Alendronate / adverse effects
  • Bone Density / drug effects
  • Bone Density / genetics
  • Bone Density Conservation Agents / administration & dosage*
  • Bone Density Conservation Agents / adverse effects
  • Bone Resorption / prevention & control*
  • Drug Combinations
  • Drug Therapy, Combination
  • Estrogens, Conjugated (USP) / administration & dosage*
  • Estrogens, Conjugated (USP) / adverse effects
  • Female
  • Genotype
  • Hormone Replacement Therapy / adverse effects
  • Hormone Replacement Therapy / methods
  • Humans
  • Medroxyprogesterone Acetate / administration & dosage*
  • Medroxyprogesterone Acetate / adverse effects
  • Middle Aged
  • Osteoporosis, Postmenopausal / drug therapy
  • Osteoporosis, Postmenopausal / genetics*
  • Prospective Studies
  • Raloxifene Hydrochloride / administration & dosage
  • Raloxifene Hydrochloride / adverse effects
  • Receptors, Calcitriol / genetics*
  • Selective Estrogen Receptor Modulators / administration & dosage
  • Selective Estrogen Receptor Modulators / adverse effects
  • Treatment Outcome

Substances

  • Bone Density Conservation Agents
  • Drug Combinations
  • Estrogens, Conjugated (USP)
  • Receptors, Calcitriol
  • Selective Estrogen Receptor Modulators
  • Raloxifene Hydrochloride
  • Medroxyprogesterone Acetate
  • Alendronate