title: Development and validation of a prognostic index for fracture risk in older men undergoing prostate cancer treatment.
abstract: OBJECTIVE
  Men treated with androgen deprivation therapy (ADT) or radiation therapy (RT) for prostate cancer have an increased risk for fractures. Given uncertainty as to whether specific clinical factors can identify men at increased risk, we sought to develop a prognostic index for risk of fracture in this population.
  
  
  METHODS
  We used the Surveillance, Epidemiology, and End Results-Medicare database to identify men who received ADT or RT after being diagnosed with localized prostate cancer in 2007-2009. Cox proportional hazards models tested the association of potential risk factors with fracture. In a derivation group, hazard ratios were used to assign points for factors independently related to fracture. The prognostic index was then applied to a validation group.
  
  
  RESULTS
  The sample of 5824 men had a median age of 73.0 years; 82.9% were white and 8.6% had a fracture within 2 years of treatment for prostate cancer. The Cox model identified 8 variables (age, race, hormone treatment, Elixhauser score, anxiety, Parkinson's, fall-inducing medications and disability status) independently associated with fracture. In the derivation cohort, 4.3% of the sample experienced a fracture in the low-risk group, 8.9% in the intermediate group, and 19.2% in the high-risk group (C statistic, 0.749). The index was applied to the validation cohort (C statistic, 0.782).
  
  
  CONCLUSIONS
  The prognostic index can help to identify patients at increased risk for fracture. This underscores the importance of identifying risk factors for fracture, given the substantial variation in fracture risk in men treated with ADT or RT.
authors.affiliation: Cancer Outcomes, Public Policy, and Effectiveness Research (COPPER) Center, Yale Comprehensive Cancer Center, Yale University School of Medicine, New Haven, CT, USA; Department of Medicine, Yale University School of Medicine, New Haven, CT, USA.
authors.forename: Tisheeka R
authors.initials: TR
authors.lastname: Graham-Steed
authors.affiliation: Cancer Outcomes, Public Policy, and Effectiveness Research (COPPER) Center, Yale Comprehensive Cancer Center, Yale University School of Medicine, New Haven, CT, USA; Department of Medicine, Yale University School of Medicine, New Haven, CT, USA.
authors.forename: Pamela R
authors.initials: PR
authors.lastname: Soulos
authors.affiliation: Bernard J. Dunn School of Pharmacy, Shenandoah University, Winchester, VA, USA.
authors.forename: Natalie
authors.initials: N
authors.lastname: Dearing
authors.affiliation: Department of Medicine, Yale University School of Medicine, New Haven, CT, USA; Clinical Epidemiology Research Center, Medical Service, Department of Veterans Affairs Connecticut HealthCare System, West Haven Veterans Affairs Medical Center, West Haven, CT, USA.
authors.forename: John
authors.initials: J
authors.lastname: Concato
authors.affiliation: Department of Medicine, Yale University School of Medicine, New Haven, CT, USA.
authors.forename: Mary E
authors.initials: ME
authors.lastname: Tinetti
authors.affiliation: Cancer Outcomes, Public Policy, and Effectiveness Research (COPPER) Center, Yale Comprehensive Cancer Center, Yale University School of Medicine, New Haven, CT, USA; Department of Medicine, Yale University School of Medicine, New Haven, CT, USA. Electronic address: cary.gross@yale.edu.
authors.forename: Cary P
authors.initials: CP
authors.lastname: Gross
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000726:Androgen Antagonists / Q000009:adverse effects / Q000627:therapeutic use; D015984:Causality; D059248:Chemoradiotherapy / Q000009:adverse effects*; D015331:Cohort Studies; D015897:Comorbidity; D050723:Fractures, Bone / Q000453:epidemiology* / Q000209:etiology; D015577:Geriatric Assessment / Q000379:methods* / Q000706:statistics & numerical data; D007987:Gonadotropin-Releasing Hormone / Q000819:agonists; D006801:Humans; D008297:Male; D057466:Nonsteroidal Anti-Androgens / Q000009:adverse effects / Q000627:therapeutic use; D011379:Prognosis; D016016:Proportional Hazards Models; D011471:Prostatic Neoplasms / Q000453:epidemiology* / Q000628:therapy*; D015203:Reproducibility of Results; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods / Q000592:standards; D012307:Risk Factors; D014481:United States / Q000453:epidemiology
chemical_list: D000726:Androgen Antagonists; D057466:Nonsteroidal Anti-Androgens; D007987:Gonadotropin-Releasing Hormone
keywords: Androgen deprivation therapy; Fractures; Prostate cancer; Radiation therapy; Risk score