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Free testosterone correlated with erectile dysfunction severity among young men with normal total testosterone
Yan-Ping Huang1, Wei Liu1, Sheng-Fu Chen2
1Department of Urology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai Institute of Andrology, No. 145, Shandong Road, Shanghai, China.
International Journal of Impotence Research
|October 24, 2018
Summary
Low free testosterone (FT) levels are linked to erectile dysfunction (ED) severity in young men, even with normal total testosterone (TT). Screening FT is recommended for ED patients with normal TT levels.
Area of Science:
- Andrology
- Endocrinology
- Urology
Background:
- Erectile dysfunction (ED) is uncommon in young men due to androgen deficiency.
- Assessing hormonal profiles is crucial for understanding ED etiology in this demographic.
Purpose of the Study:
- To investigate the association between testosterone levels and erectile function in men aged 18-40 with ED.
- To determine if free testosterone (FT) is a better predictor of ED severity than total testosterone (TT) in young men.
Main Methods:
- Retrospective study of 140 men (18-40 years) with ED.
- Assessed erectile function using the International Index of Erectile Function-5 (IIEF-5) and Erection Hardness Grade Scores (EHGS).
- Measured total testosterone (TT), sex hormone-binding globulin (SHBG), and calculated free (FT) and bio-available testosterone (BT); adjusted for BMI, smoking, and comorbidities.
Main Results:
- Decreased FT levels correlated with lower IIEF-5 scores and EHGS.
- Total testosterone (TT) showed a weaker association with erectile function, primarily in crude models.
- Free testosterone (FT) levels were associated with ED severity, independent of normal TT levels.
Conclusions:
- Low FT, even with normal TT, is significantly associated with ED severity in young men.
- Screening FT levels is advised for young men presenting with ED, irrespective of their TT levels.
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