Background: Data regarding the impact of symptomatic skeletal events (SSEs) on health economics and patient-reported outcomes in men with castration-resistant prostate cancer (CRPC) and bone metastases from a clinical setting are lacking. Hence, this study aimed to quantify the effects of SSEs on health-care resource utilization (HRU), health-related quality of life (HRQoL) and pain in men with CRPC metastasized to bone.
Methods: This cohort study included men with CRPC and bone metastasis treated at a tertiary center during December 1996-July 2015. SSEs, including pathological fracture, radiation to bone, spinal cord compression and bone surgery, as well as HRU were identified retrospectively through medical records and clinical database. A subset of surviving patients completed Functional Assessment of Cancer Therapy-Prostate (FACT-P) and Brief Pain Inventory-Short Form (BPI-SF) questionnaires. The incremental effect of SSEs on HRU was evaluated using multivariable generalized linear regression. Questionnaire scores were compared using effect sizes (ES); ES⩾0.33 indicated meaningful differences between SSE and non-SSE cohorts. Lower scores suggest lower HRQoL and pain.
Results: Of the 832 patients, 207 developed ⩾1 SSE (mean 1.5±0.8) during follow-up (median 2.1 years). Radiation to bone was the most common SSE (84.1%). SSE cohort had significantly higher emergency room (incidence rate ratio (IRR)=1.48; P=0.006), outpatient (IRR=1.17; P=0.005) and inpatient (IRR=1.74; P<0.001) visits. Of the 107 eligible survey patients, 103 (96.3%) responded. SSE cohort had lower mean FACT-P functional well-being (17.5 vs 19.8; P=0.158; ES=0.36), higher mean pain severity (2.5 vs 1.6; P=0.048; ES=0.47) and worst pain scores (3.6 vs 2.3; P=0.033; ES=0.50) compared with the non-SSE cohort, indicating meaningful differences between cohorts.
Conclusions: This study demonstrated high economic and HRQoL burden of SSEs. The findings underscore the need for better supportive and disease-modifying treatments for these patients.