High estrogen in men after injectable testosterone therapy: the low T experience

Area of Science:

• Endocrinology
• Men's Health
• Sexual Medicine

Background:

• Testosterone replacement therapy (TRT) aims to improve quality of life.
• Estrogen, produced via aromatization of testosterone in adipose tissue, is implicated in male sexual health.
• Hyperestrogenism is often considered detrimental to male sexuality.

Purpose of the Study:

• To analyze the prevalence of high estradiol levels in men receiving TRT.
• To investigate the relationship between estradiol levels and libido in men undergoing TRT.
• To examine age-related trends in estradiol levels among these patients.

Main Methods:

• Retrospective analysis of electronic health records from 35 Low T Centers (2009-2014).
• Data from 34,016 men, with 7,215 (20.2%) identified with high estradiol (≥42.6 pg/ml).
• Estradiol measured by electro-chemiluminescence immunoassay; statistical analysis included chi-square tests and correlation coefficients.

Main Results:

• High estradiol levels (≥42.6 pg/ml) were found in 20.2% of the screened male population.
• A statistically significant correlation was observed between serum estradiol and age (r=0.53).
• Contrary to expectations, high estradiol levels were not associated with increased rates of low libido; rather, normal or low levels correlated with higher documented rates of low libido (p < .05).

Conclusions:

• Elevated estradiol levels in men on TRT do not appear to be a primary driver of low libido.
• The study suggests a potential inverse relationship between estradiol levels and libido, warranting further investigation.
• Clinical practice involved using aromatase inhibitors and SERMs for hyperestrogenism symptoms, often irrespective of estradiol levels.