Impact of skeletal complications on total medical care costs in prostate cancer patients with bone metastases

Abstract

6057 Background: Prostate cancer patients with bone metastases often experience skeletal-related events (SREs) including pathological fracture, spinal cord compression, or pain requiring surgery, radiotherapy, or opioid analgesics. Previous studies have estimated the costs of SREs by tallying costs for services specifically attributable to these events. This approach may underestimate costs if SREs have effects on other services. Methods: We used a large US health insurance claims database (7/94 - 6/02) to quantify impact of SREs on total medical care costs in patients with bone metastases of prostate cancer. Subjects included in this analysis had ≥2 encounters with a diagnosis of primary prostate cancer and ≥2 encounters with a diagnosis of metastases to bone. Expected total medical care costs were compared for propensity-matched samples of patients with SREs versus patients without SREs. SREs were identified based on the occurrence on or after the date of first diagnosis of bone metastases, of (1) ≥1 encounter with a diagnosis of pathological fracture or spinal cord compression, or (2) ≥1 bone surgery or radiotherapy procedure, or (3) initiation of opioid analgesic therapy. Results: We identified 542 prostate cancer patients with bone metastases, including 282 (52%) with ≥1 SRE. After matching, there were 181 patients each in the SRE and no-SRE groups with mean follow-up of 13 and 10 months respectively. In the SRE group, expected costs of care directly attributable to SREs were $9,783 per patient. Expected total medical-care costs were $20,484 greater in SRE patients ($59,522 vs $39,038 in the no-SRE group) Conclusions: The costs of SREs in patients with prostate cancer and bone metastases are substantial and potentially greater than previously estimated. Treatments which prevent SREs, such as the intravenous bisphosphonate zoledronic acid, may reduce these costs. Author Disclosure Employment or Leadership Consultant or Advisory Stock Ownership Honoraria Research Funding Expert Testimony Other Remuneration Novartis Novartis Novartis Aventis Oncology