title: Determinants of change in bone mineral density and fracture risk during bisphosphonate holiday.
abstract: In a retrospective analysis of 208 osteoporotic patients followed during a bisphosphonate holiday, lower body weight and risedronate use were associated with a more rapid decline in bone mineral density during the bisphosphonate holiday, while bone mineral density (BMD) trends were similar in patients who sustained vs. did not sustain a fracture.
  
  
  BACKGROUND
  A drug holiday has been suggested for some bisphosphonate-treated patients with osteoporosis to minimize potential side effects from prolonged use. However, there is limited information on the evolution of BMD during a bisphosphonate holiday. Our study analyzed the longitudinal course of BMD following bisphosphonate discontinuation and assessed its determinants.
  
  
  METHODS
  Retrospective single-center cohort study of osteoporosis patients treated with alendronate or risedronate for at least 2 years and then discontinued their bisphosphonate for a drug holiday. Patients were stratified by bisphosphonate type and by fracture occurrence during drug holiday.
  
  
  RESULTS
  A total of 208 patients were included in this analysis (87.5 % female). At the time of bisphosphonate cessation, mean ± SD age was 66.9 ± 8.9 years and BMI 24.5 ± 4.4 kg/m(2). Duration of bisphosphonate treatment was 5.2 ± 2.3 years, and follow-up during holiday was 3.3 ± 1.7 years. During the first 2 years of the holiday, BMD remained stable at the lumbar spine and femoral neck, but declined significantly at the total hip. BMD declined significantly at all sites thereafter. Significant predictors of BMD decline during bisphosphonate holiday included lower BMI at the start of the holiday and change in body weight during the holiday. BMD decline was more pronounced in former risedronate compared to former alendronate users. BMD trends were similar in patients who sustained vs. did not sustain a fracture during the holiday.
  
  
  CONCLUSIONS
  BMD at the total hip declines significantly within 1 year of bisphosphonate discontinuation, particularly in lean patients. Additional studies are needed to identify predictors of fracture incidence during a bisphosphonate holiday.
authors.affiliation: Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390-8885, USA.
authors.forename: L H R
authors.initials: LH
authors.lastname: Xu
authors.affiliation: Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390-8885, USA.|Department of Clinical Sciences, University of Texas Southwestern Medical Center, Dallas, TX, USA.
authors.forename: B
authors.initials: B
authors.lastname: Adams-Huet
authors.affiliation: Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390-8885, USA.
authors.forename: J R
authors.initials: JR
authors.lastname: Poindexter
authors.affiliation: Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390-8885, USA. nmaalouf@hotmail.com.|Endocrine Section, Medical Service, Veterans Affairs North Texas Health Care System, Dallas, TX, USA. nmaalouf@hotmail.com.
authors.forename: N M
authors.initials: NM
authors.lastname: Maalouf
mesh_terms: D000368:Aged; D019386:Alendronate / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use; D001835:Body Weight / Q000502:physiology; D015519:Bone Density / Q000187:drug effects*; D050071:Bone Density Conservation Agents / Q000008:administration & dosage* / Q000494:pharmacology / Q000627:therapeutic use; D004164:Diphosphonates / Q000008:administration & dosage* / Q000494:pharmacology / Q000627:therapeutic use; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010024:Osteoporosis / Q000150:complications / Q000188:drug therapy* / Q000503:physiopathology; D015663:Osteoporosis, Postmenopausal / Q000150:complications / Q000188:drug therapy / Q000503:physiopathology; D058866:Osteoporotic Fractures / Q000209:etiology* / Q000503:physiopathology / Q000517:prevention & control; D012189:Retrospective Studies; D000068296:Risedronic Acid / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use; D018570:Risk Assessment; D028761:Withholding Treatment
chemical_list: D050071:Bone Density Conservation Agents; D004164:Diphosphonates; D000068296:Risedronic Acid; D019386:Alendronate
keywords: Bisphosphonate; Bone mineral density; Drug holiday; Fracture; Osteoporosis