The association between the use of testosterone replacement therapy (TRT) and prostate cancer remains uncertain. Thus, we investigated whether TRT is associated with an increased risk of prostate cancer in men with late-onset hypogonadism. We used the United Kingdom Clinical Practice Research Datalink to assemble a cohort of 12,779 men newly-diagnosed with hypogonadism between 1 January 1995 and 31 August 2016, with follow-up until 31 August 2017. Exposure to TRT was treated as a time-varying variable and lagged by 1 year to account for cancer latency, with non-use as the reference category. During 58,224 person-years of follow-up, a total of 215 patients were newly-diagnosed with prostate cancer, generating an incidence rate of 3.7 per 1,000 person-years. In time-dependent Cox proportional hazards models, use of TRT was not associated with an overall increased risk of prostate cancer (hazard ratio = 0.97; 95% confidence interval: 0.71, 1.32), compared with non-use. Results remained consistent in secondary and sensitivity analyses, as well as in a propensity score-matched cohort analysis that further assessed the impact of residual confounding. Overall, the use of TRT was not associated with an increased risk of prostate cancer in men with late-onset hypogonadism.
American journal of epidemiology. 2019 May 30 [Epub ahead of print]
Christina Santella, Christel Renoux, Hui Yin, Oriana H Y Yu, Laurent Azoulay
Centre for Clinical Epidemiology, Lady Davis Institute, Jewish General Hospital, Montreal, Quebec, Canada.