Androgen deprivation therapy and overall survival after hip fracture surgery in patients with prostate cancer

Abstract

Background and aims: Androgen deprivation therapy (ADT), either by surgical or chemical castration, is the standard treatment for metastatic prostate cancer (PCa). ADT induces osteoporosis and increases the risk of osteoporotic fractures, such as hip fractures. However, the effect of castration on overall survival (OS) after hip fracture is unclear. The aim of this study was to evaluate the association between ADT and OS among PCa patients with surgically treated low-energy hip fractures. Methods: Male patients with surgically treated low-energy hip fractures (ICD-10 codes S72.0, S72.1, and S72.2) were retrospectively identified from the databases of Pirkanmaa Hospital District during the years 2002–2018. Patients with pathological hip fractures were excluded from the analysis. Patients with prior PCa were identified (n = 323) and categorized into three groups according to therapy that affects testosterone levels: no hormonal therapy (n = 94), ADT (n = 212), and nonsteroidal antiandrogen (NSAA) (n = 17) at the time of the fracture. The primary outcome was OS after hip fracture surgery. Postoperative OS was analyzed using the Kaplan–Meier method, and the difference in OS between groups was analyzed using Cox regression in univariable, age-adjusted, and multivariable-adjusted models. Results: Kaplan–Meier survival analysis suggested that patients under ADT had shorter OS after hip fracture surgery (p = 0.006). After adjustment for potential confounders in Cox regression models, no clear association was observed between ADT (hazard ratio (HR) 1.19, 95% confidence interval (CI) 0.90–1.58) or NSAA (HR 1.02 (0.59–1.78)) and OS when compared to patients with PCa not undergoing hormonal therapy. Higher age and comorbidities, rather than ADT, appeared to be associated with poorer OS. Conclusions: In the cohort of patients with PCa, who underwent surgery for low-energy hip fracture, ADT or NSAA utilization was not associated with OS. Wide CIs allow for both modest benefit and potential harm, and the findings should therefore be considered inconclusive.