The Cost of Treatment of Skeletal-Related Events in Patients with Bone Metastases from Lung Cancer

Abstract

Purpose: Patients with bone metastases from lung cancer often experience skeletal-related events (SREs) including pathological fracture, spinal cord compression, hypercalcemia or pain requiring surgery, radiotherapy or opioid analgesics. These complications result in impaired mobility and reduced quality of life and have a significant negative impact on survival. The economic consequences of SREs in patients with lung cancer have not been examined. Methods: We conducted a retrospective analysis using a large US health insurance claims database to estimate the incidence and costs of treatment of SREs in patients with bone metastases of lung cancer treated in a naturalistic setting. Study subjects had ≧2 encounters with a diagnosis of primary lung cancer and ≧2 encounters with a diagnosis of metastases to bone. 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, spinal cord compression or hypercalcemia, (2) ≧1 bone surgery or radiotherapy procedure, or (3) the initiation of opioid analgesic therapy. Survival and costs of SRE-related care in patients with SREs were estimated using Kaplan-Meier methods. Results: We identified 534 patients with lung cancer and bone metastases, including 295 (55%) with ≧1 SRE. Radiotherapy (68%) and fracture (35%) were the most common SREs. Median survival after the first identified SRE was 4.1 months (95% confidence interval: 3.6–5.5 months). The estimated lifetime SRE-related cost per patient was USD 11,979 (95% confidence interval: USD 10,193–13,766). Radiotherapy accounted for the greatest proportion of cost (61%) by SRE type. Conclusion: The economic burden of SREs in patients with bone metastases of lung cancer is substantial. Intravenous bisphosphonates, such as zoledronic acid, which have been shown to prevent these events, may reduce these costs.