Osteoporosis International

, 20:1259

Vitamin D insufficiency does not affect response of bone mineral density to alendronate

Authors

    • Endocrine Research Unit, Department of Medicine, San Francisco Department of Veterans Affairs Medical CenterUniversity of California
  • E. Vittinghoff
    • Department of EpidemiologyUniversity of California
  • L. Palermo
    • Department of EpidemiologyUniversity of California
  • D. M. Black
    • Department of EpidemiologyUniversity of California
  • D. E. Sellmeyer
    • Division of Endocrinology, Department of MedicineUniversity of California
Original Article

DOI: 10.1007/s00198-008-0799-4

Cite this article as:
Antoniucci, D.M., Vittinghoff, E., Palermo, L. et al. Osteoporos Int (2009) 20: 1259. doi:10.1007/s00198-008-0799-4

Abstract

Summary

We investigated whether osteoporosis therapy with alendronate in postmenopausal patients is equally effective in patients who are vitamin D insufficient as in those who are vitamin D sufficient. We found that vitamin D insufficiency is common among patients with low bone density but that vitamin D insufficiency did not impair response to alendronate.

Introduction

Treatment of vitamin D deficiency leads to significant improvements in bone mineral density (BMD); however, whether insufficiency affects BMD’s response to bisphosphonate therapy is unknown.

Methods

To determine whether vitamin D insufficiency at initiation of alendronate therapy for low BMD affects treatment efficacy, we used data from 1,000 postmenopausal women randomly selected from the vertebral fracture arm (n = 2,027) of the placebo-controlled Fracture Intervention Trial of alendronate. Participants were randomly assigned to placebo (50%) or alendronate therapy and most (83%) to calcium (500 mg/day) and cholecalciferol (250 IU/day). We measured serum 25-hydroxy vitamin D (25OHD) at enrollment, then categorized baseline vitamin D status according to 25OHD concentration ( ≤ 10 ng/ml = deficient; >10 but ≤ 30 ng/ml = insufficient; >30 ng/ml = sufficient) and used linear regression to compare the effects of alendronate treatment among these categories.

Results and conclusion

At baseline, participants were vitamin D sufficient (14%), insufficient (83%), and deficient (2%). We found that BMD response to therapy at total hip or spine did not vary by vitamin D status at baseline (p for heterogeneity = 0.6). We determined that vitamin D insufficiency is common among participants with low BMD. However, vitamin D status at initiation of therapy does not affect BMD’s response to alendronate, when it is coadministered with cholecalciferol and calcium.

Keywords

AlendronateBone mineral densityOsteoporosisVitamin D deficiencyVitamin D repletion

Copyright information

© International Osteoporosis Foundation and National Osteoporosis Foundation 2008