Androgen deprivation therapy for prostate cancer and the risk of thyroid diseases

Background: Androgen deprivation therapy (ADT) is the major treatment for metastatic prostate cancer (PCa), but few studies have investigated the effects of ADT on thyroid diseases. Methods: This population-based, nationwide cohort study utilized the Taiwan National Health Insurance Research Database (NHIRD) with 17,192 PCa patients between 1997 and 2013. We used the Cox proportional hazards models and propensity score-matched analysis to analyze the association between ADT and the development of thyroid diseases. Results: A total of 17,192 newly diagnosed men with PCa were selected from the NHIRD. There were 6200 ADT users and 6200 non-ADT users after 1:1 propensity score matching. There was a significantly decreased risk of thyroid diseases among ADT users compared with non-ADT users (adjusted hazard ratio (aHR): 0.79, 95% confidence interval (CI): 0.65–0.95, p < 0.001). Further analysis showed a significantly decreased risk of thyroid diseases with increasing ADT duration (p < 0.001). Conclusions: The result showed that ADT use in men with PCa was associated with a decreased risk of thyroid disease development.