Testosterone and Prostate cancer
Clin Endocrinol (Oxf). 2019 Sep 9. doi: 10.1111/cen.14093. [Epub ahead of print]
Another study showing that testosterone does not increase the risk of getting prostate cancer. In fact, there was a 33% reuction in prostate cancer in those men on testosterone therapy.
Association of the extent of therapy with prostate cancer in those receiving testosterone therapy in a US commercial insurance claims database.
1Deparment of Preventive Medicine and Community Health, University of Texas Medical Branch, Galveston, TX, USA.2Department of Hygiene and Epidemiology, University of Ioannina School of Medicine, Ioannina, Greece.3Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London, UK.4Scott Department of Urology at Baylor College of Medicine, Houston, TX, USA.5Division of Urology, Department of Surgery, University of Texas Medical Branch, Galveston, TX, USA.6Department of Internal Medicine, University of Texas Medical Branch, Galveston, TX, USA.7Department of Policy and Practice, School of Public Health, Brown University, Providence, RI, USA.8Department of Preventive Medicine, Norris Comprehensive Cancer Center, Gehr Family Center for Health Systems Science, Keck School of Medicine of the University of Southern California, Los Angeles, CA, USA.9UTHealth School of Public Health, Houston, TX, USA.
Conflicting evidence remains in the association of testosterone therapy (TTh) with prostate cancer (PCa). This inconsistency maybe due, in part, to the small sample sizes from previous studies and an incomplete assessment of comorbidities, particularly diabetes.
We investigated the association of PCa with TTh (injection or gel) and different TTh doses and determined whether this association varies by the presence of diabetes at baseline in a large, nationally representative, commercially insured cohort.
We conducted a retrospective cohort study of 189 491 men aged 40-60 years old in the IBM MarketScan® Commercial Database, which included 1424 PCa cases diagnosed from 2011 to 2014. TTh was defined using CPT codes from inpatient and outpatient, and NDC codes from pharmacy claims. Multivariable adjusted Cox proportional hazards models were used to compute hazard ratios for patients with incident PCa.
We found a 33% reduced association of PCa after comparing the highest category (>12) of TTh injections with the lowest (1-2 injections) category (HR = 0.67, 95% CI: 0.54-0.82). Similar statistical significant inverse association for PCa was observed for men who received TTh topical gels (>330 vs 1- to 60-days supply). Among nondiabetics, we found significant inverse association between TTh (injection and gel) and PCa, but a weak interaction between TTh injections and diabetes (P = .05).
Overall, increased use of TTh is inversely associated with PCa and this remained significant only among nondiabetics. These findings warrant further investigation in large randomized placebo-controlled trials to infer any health benefit by TTh.