Effects of age on outcomes in men receiving treatment for metastatic castration-resistant prostate cancer (mCRPC): Analysis of Medicare fee for service (FFS) claims data.

Abstract

e17590 Background: Because elderly patients may exhibit differences in immune activation, we evaluated outcomes in men receiving first line treatment for mCRPC with sip-T or oral agents (ie, abiraterone acetate or enzalutamide) by age. Methods: Claims data from the 2013-2017 Centers for Medicare and Medicaid Services Fee for Service 100% Medicare Identifiable Database for Parts A, B and D were examined. We evaluated with index dates in 2014 and 3 years of follow-up. Patients were categorized by age (Table) and agent use as per Healthcare Common Procedure Coding System codes and National Drug Codes. First line use of sip-T vs oral agents was examined as was any line use of sip-T vs oral agents (without sip-T). Kaplan-Meier methodology was used to assess survival with Cox proportional hazards regression modelling used to calculate hazard ratios (HR). Results: Mean ages of men receiving sip-T and orals were 76 and 78 years, respectively. Most (84%) were white. Regardless of line of use, the risk of death among men receiving sip-T was lower than the risk in men receiving orals, except in men over 90 years old (Table). Conclusions: Based on these claims data, benefits of sip-T use were evident across all ages except for the men 90+ years old with decreasing differences between agents with increasing age, as would be expected. While the oral agents may be perceived as more convenient, greater survival with sip-T suggests that clinicians should consider use of sip-T therapy for mCRPC, irrespective of age. [Table: see text]