title: Assessment of zoledronic acid treatment patterns and clinical outcomes in patients with bone metastases from genitourinary cancers.
abstract: BACKGROUND
  Patients with bone metastases secondary to genitourinary (GU) cancer are at risk for skeletal-related events (SREs), including bone pain requiring palliative radiotherapy, fractures or surgery to bone, spinal cord compression, and hypercalcemia of malignancy. These SREs can be debilitating and potentially life-limiting. This study examined treatment practices and the association of treatment patterns with Zometa (zoledronic acid, ZOL), an intravenous bisphosphonate (IV-BP), with SREs and fractures. (Zometa is a registered trademark of Novartis Pharmaceuticals Corporation, USA.)
  
  
  METHODS
  Retrospective analysis of commercial and Medicare Advantage enrollment and medical claims data was performed to evaluate IV-BP use and SRE patterns in adult patients with GU cancers. Criteria included diagnosis of ≥1 bone metastasis and prostate cancer (PC), renal cell carcinoma (RCC), or bladder cancer (BlC) between January 2001 and December 2006; continuous healthcare plan enrollment for ≥6 months before the index date; and no evidence of prior IV-BP use. Patients were followed until disenrollment from the healthcare plan or December 2007.
  
  
  RESULTS
  Of 6347 patients (PC, n = 4976; RCC, n = 941; BlC, n = 430; mean [standard deviation] age: 68.9 [11.1] years), only approximately 23% received ZOL. The mean time between diagnosis of bone metastasis and ZOL initiation was approximately 108 days. Among patients with PC, fracture risk was significantly smaller for ZOL vs no IV-BP (incidence rate ratio = 0.70; p < 0.001), and 2-year survival was significantly longer for ZOL-treated vs no IV-BP patients (p = 0.007). Patients with longer persistency on ZOL had a smaller fracture risk than patients with shorter persistency. Sub-set analyses were not performed for RCC and BIC because the proportion of patients treated was too low.
  
  
  CONCLUSIONS
  Interpretation of this claims-based analysis must be tempered by the inherent limitations of observational data, such as limited and accurate available information, and unavailable information including clinical or disease-specific parameters.
  
  
  CONCLUSIONS
  Intravenous BP therapy is not always received in patients with bone metastases secondary to GU cancers, and, when used, there are typically long time periods before treatment initiation. Without IV-BPs, PC patients have significantly larger risks of fracture and death compared with ZOL-treated patients, and benefits appear to be larger with increasing persistency on ZOL.
authors.affiliation: OptumInsight, Health Economics and Outcomes Research, Eden Prairie, MN 55344, USA. henry.henk@innovus.com
authors.forename: Henry J
authors.initials: HJ
authors.lastname: Henk
authors.forename: Satyin
authors.initials: S
authors.lastname: Kaura
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D050071:Bone Density Conservation Agents / Q000627:therapeutic use*; D001859:Bone Neoplasms / Q000556:secondary*; D004164:Diphosphonates / Q000627:therapeutic use*; D005260:Female; D050723:Fractures, Bone / Q000453:epidemiology / Q000517:prevention & control; D006801:Humans; D007093:Imidazoles / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D016019:Survival Analysis; D014481:United States / Q000453:epidemiology; D014565:Urogenital Neoplasms / Q000401:mortality / Q000473:pathology*; D000077211:Zoledronic Acid
chemical_list: D050071:Bone Density Conservation Agents; D004164:Diphosphonates; D007093:Imidazoles; D000077211:Zoledronic Acid