Meta-analysis on the Influence of Testosterone Therapy on Male Kidney Function

Objective: Testosterone plays a significant role in kidney function. Both hypogonadism and hypergonadism, which can affect testosterone levels, have been associated with alterations in kidney function. This review provides a comprehensive and up-to-date overview of the potential impact of testosterone therapy on kidney function among male patients.
Method: We conducted a systematic review and meta-analysis following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Comprehensive search through Scopus, Embase, and Web of Science databases, with publications included up to June 11, 2023. Eligible studies included adult men aged 18 years and older who received testosterone therapy and reported kidney function outcomes, including randomized controlled trials (RCTs), and observational studies (prospective, retrospective, or case-control). Exclusion criteria included reviews, non-original articles, studies involving non-human subjects, duplicate reports, and studies with insufficient data. Statistical analysis was performed using a random-effects model, and variability was assessed using I². The review protocol was registered with PROSPERO (CRD42023456010).
Results: Out of 13 articles, encompassing 39,692 individuals in the treatment group and 10,375 in the control group from studies conducted in seven different countries. The meta-analysis revealed a noticeable difference in age (MD= -0.56; 95% CI: -0.68, -0.45; p<0.001). Testosterone levels were significantly lower in the control group (MD= -0.41; 95% CI: -0.52, -0.30; p<0.001). Baseline blood urea nitrogen concentration was significantly higher in the testosterone treatment group than in the control group, with this difference being statistically significant (MD= 1.66; 95% CI: 1.10, 2.23; p<0.001). Following treatment, blood urea nitrogen was lower in the testosterone treatment group than in the control group, though this difference was not statistically significant (MD= -0.44; 95% CI: -0.93, 0.05; p=0.079). The difference in uric acid levels between the treatment and control groups was not statistically significant (MD= 0.11; 95% CI: -0.02, 0.24; p=0.08). While these non-significant findings may not directly indicate a clinically meaningful impact, they still highlight potential trends that should be explored further, especially considering that BUN and uric acid levels are important markers of kidney function and could be influenced by testosterone therapy over the long term.
Conclusion: Testosterone therapy may influence kidney function, though further studies are needed to clarify its long-term effects and clinical significance.