Cardiovascular Risks and Elevation of Serum DHT Vary by Route of Testosterone Administration: A Systematic Review and Meta-Analysis

This systematic review and meta-analysis, which included 35 studies with 3,703 older men, examined the cardiovascular (CV) risks associated with different routes of testosterone replacement therapy (TRT). The study found that oral TRT significantly increased CV risk (relative risk (RR) = 2.20), while intramuscular and transdermal TRT did not show significant effects on CV risk. Additionally, transdermal TRT elevated serum dihydrotestosterone (DHT) levels more than intramuscular TRT, which might be linked to increased CV risk. The findings suggested that the route of TRT administration could influence CV risk, highlighting the need for further research to clarify these effects and the implications of DHT elevation.