title: WITHDRAWN: Risedronate for the prevention and treatment of postmenopausal osteoporosis.
abstract: BACKGROUND
  Postmenopausal osteoporosis results in an increased susceptibility to low-trauma fractures due to reduced bone volume and microarchitectural deterioration. Risedronate, a third generation bisphosphonate, has been shown in multiple clinical trials to reduce fracture risk and improve bone mineral density in postmenopausal women with osteoporosis. First and second generation bisphosphonates are known to have gastrointestinal side-effects and risedronate may be better tolerated.
  
  
  OBJECTIVE
  To systematically review the efficacy of risedronate on bone density, and fracture reduction in postmenopausal women.
  
  
  METHODS
  The Cochrane Controlled Trials Registry Medline, and Current Contents were searched from 1990 - 2001. The electronic search was supplemented by handsearching four osteoporosis journals and their conference proceedings, as well as contacting content experts and industry sources for unpublished data.
  
  
  METHODS
  We included eight trials that randomised women to risedronate or an alternative (placebo or calcium and /or vitamin D) and measured bone mineral density for at least one year.
  
  
  METHODS
  For each trial three independent reviewers assessed the methodological quality and abstracted data. Data was extracted for outcomes of fracture, bone mineral density and adverse events. The more conservative random effects model was used to pool data. The quality of trials was assessed according to the Jadad five-point scale.
  
  
  RESULTS
  Both vertebral and non-vertebral fractures were statistically and clinically reduced with risedronate. Eleven out of one hundred women who received risedronate had a vertebral fracture compared to 17 out of one hundred of those who received calcium and vitamin D (pooled relative risk for vertebral fractures of 0.64 (95% CI 0.52 - 0.77). Three percent of participants who received risedronate had a non-vertebral fracture compared to 4.6% of those who received calcium and vitamin D (pooled relative risk for nonvertebral fractures of 0.73 (95% CI 0.61 - 0.87). The weighted mean difference for the percent change from baseline for bone mineral density with 5 mg daily for lumbar spine, femoral neck and trochanter was 4.54% (95%CI 4.12 - 4.97), p<0.01; 2.75% (95% CI 2.32 - 3.17), p<0.01; and 4.38% (95% CI 3.51 - 5.25), p<0.01 respectively.
  
  
  CONCLUSIONS
  There is good evidence for the efficacy of risedronate in the reduction of both vertebral and non-vertebral fractures. In addition, there is evidence from randomized trials that risedronate is able to achieve this without increasing risk for overall withdrawals due to adverse effects.
authors.affiliation: Ottawa Hospital, Division of Rheumatology, 1053 Carling Ave, Ottawa, Ontario, Canada, K1Y 4E9. ancranney@ohri.ca
authors.forename: A
authors.initials: A
authors.lastname: Cranney
authors.forename: J D
authors.initials: JD
authors.lastname: Adachi
authors.forename: G
authors.initials: G
authors.lastname: Guyatt
authors.forename: A
authors.initials: A
authors.lastname: Papaioannou
authors.forename: V A
authors.initials: VA
authors.lastname: Robinson
authors.forename: B J
authors.initials: BJ
authors.lastname: Shea
authors.forename: P
authors.initials: P
authors.lastname: Tugwell
authors.forename: L M
authors.initials: LM
authors.lastname: Waldegger
authors.forename: B
authors.initials: B
authors.lastname: Weaver
authors.forename: G
authors.initials: G
authors.lastname: Wells
authors.forename: N
authors.initials: N
authors.lastname: Zytaruk
mesh_terms: D015519:Bone Density / Q000187:drug effects*; D012968:Etidronic Acid / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000627:therapeutic use*; D005260:Female; D050723:Fractures, Bone / Q000517:prevention & control*; D006801:Humans; D015663:Osteoporosis, Postmenopausal / Q000188:drug therapy* / Q000517:prevention & control; D016032:Randomized Controlled Trials as Topic; D016103:Spinal Fractures / Q000517:prevention & control
chemical_list: D012968:Etidronic Acid