How should we monitor men receiving testosterone replacement therapy?

Testosterone lowers total cholesterol
A meta-analysis of 30 RCTs (1642 men, 808 on testosterone therapy, 834 on placebo) that assessed testosterone’s effect on lipid levels found that testosterone reduced total cholesterol levels by 16 mg/dL (95% CI, 6-26 mg/dL); effects on all other lipid fractions weren’t significant.⁵

A second meta-analysis of 16 RCTs (578 men, 320 on testosterone therapy, 258 on placebo) similarly showed that testosterone lowered total cholesterol levels by 8 mg/dL (95% CI, 4-14 mg/dL) and that its effects on other lipid fractions weren’t significant.² The previously mentioned meta-analyses of 19 and 30 RCTs found no significant difference in cardiovascular events between testosterone- and placebo-treated groups.^1,5

Optimal testosterone level is unknown
Data are inadequate to determine the optimal serum level of testosterone for efficacy and safety.³ Expert opinion suggests that because therapy is empiric, monitoring clinical response may help guide treatment more than testosterone level.⁶

What about the liver?
Oral testosterone can be associated with hepatotoxicity; it is seldom used in the United States. Liver monitoring is unnecessary for patients receiving testosterone by injection, patch, or transbuccal tablet.^7,8

Recommendations

Consensus guidelines for monitoring men on testosterone therapy overlap considerably with regard to monitoring clinical effectiveness, prostate measures, hematocrit, and BMD (TABLE).^3,6,9,10 Assessing testosterone level is recommended, with the aim of achieving levels in the mid-normal range.¹⁰

Table
Monitoring testosterone therapy: What the consensus guidelines say