title: A cohort study of thiazolidinediones and fractures in older adults with diabetes.
abstract: BACKGROUND
  Thiazolidenediones (TZDs) are selective ligands of peroxisome-proliferator-activated receptor-gamma and have been shown to reduce bone mineral density. Recent results from several randomized controlled trials find an increased risk of fracture with TZDs compared with other oral antidiabetic agents.
  
  
  OBJECTIVE
  The aim of the study was to determine the association between TZD use and fracture risk among older adults with diabetes.
  
  
  METHODS
  We conducted a cohort study.
  
  
  METHODS
  Medicare beneficiaries with at least one diagnosis of diabetes initiating monotherapy for an oral hypoglycemic agent participated in the study.
  
  
  RESULTS
  We measured the incidence of fracture within the cohort.
  
  
  RESULTS
  Among the 20,964 patients with diabetes eligible for this study, 686 (3.3%) experienced a fracture during the median follow-up of approximately 10 months. Although not statistically significant, patients using only a TZD were more likely to experience a fracture than those using metformin (adjusted relative risk, 1.31; 95% confidence interval, 0.98-1.77; P = 0.071) or a sulfonylurea (adjusted relative risk, 1.21; 95% confidence interval, 0.94-1.55; P = 0.12). Each individual TZD was associated with an increased risk, with confidence intervals overlapping unity, compared with both metformin and sulfonylureas. The adjusted risk of any fracture associated with TZD use compared with metformin was elevated for non-insulin-using patients, women and men. If TZD use is associated with fractures, the number needed for one excess fracture when comparing TZD users to sulfonylurea users was 200, and the number was 111 when comparing TZDs with metformin.
  
  
  CONCLUSIONS
  As has been found with other analyses, our data suggest that TZDs may be associated with an increased risk of fractures compared with oral sulfonylureas and metformin.
authors.affiliation: Division of Rheumatology, Brigham and Women's Hospital, 75 Francis Street, Boston, MA 02115, USA. dsolomon@partners.org
authors.forename: Daniel H
authors.initials: DH
authors.lastname: Solomon
authors.forename: Suzanne M
authors.initials: SM
authors.lastname: Cadarette
authors.forename: Niteesh K
authors.initials: NK
authors.lastname: Choudhry
authors.forename: Claire
authors.initials: C
authors.lastname: Canning
authors.forename: Raisa
authors.initials: R
authors.lastname: Levin
authors.forename: Til
authors.initials: T
authors.lastname: Stürmer
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D003920:Diabetes Mellitus / Q000188:drug therapy*; D005260:Female; D050723:Fractures, Bone / Q000139:chemically induced*; D006801:Humans; D007004:Hypoglycemic Agents / Q000009:adverse effects*; D008297:Male; D008687:Metformin / Q000009:adverse effects; D012306:Risk; D013453:Sulfonylurea Compounds / Q000009:adverse effects; D045162:Thiazolidinediones / Q000009:adverse effects*
chemical_list: D007004:Hypoglycemic Agents; D013453:Sulfonylurea Compounds; D045162:Thiazolidinediones; D008687:Metformin