scholarly journals Evaluation of the influence of pre-analytical factors on total testosterone levels in healthy young men

Author(s):  
Isabela L. Lima ◽  
Isabelly M. Neves ◽  
Izabela R. Costa ◽  
Matheus C. Caplum ◽  
Pedro C. B. Oliveira ◽  
...  
2006 ◽  
Vol 91 (11) ◽  
pp. 4669-4675 ◽  
Author(s):  
Andrea D. Coviello ◽  
Kishore Lakshman ◽  
Norman A. Mazer ◽  
Shalender Bhasin

Abstract Background: Recently we found that testosterone levels are higher in older men than young men receiving exogenous testosterone. We hypothesized that older men have lower apparent testosterone metabolic clearance rates (aMCR-T) that contribute to higher testosterone levels. Objective: The objective of the study was to compare aMCR-T in older and young men and identify predictors of aMCR-T. Methods: Sixty-one younger (19–35 yr) and 60 older (59–75 yr) men were given a monthly GnRH agonist and weekly testosterone enanthate (TE) (25, 50, 125, 300, or 600 mg) for 5 months. Estimated aMCR-T was calculated from the amount of TE delivered weekly and trough serum testosterone concentrations, corrected for real-time absorption kinetics from the im testosterone depot. Results: Older men had lower total (316 ± 13 vs. 585 ± 26 ng/dl, P < 0.00001) and free testosterone (4 ± 0.1 vs. 6 ± 0.3 ng/dl, P < 0.00001) and higher SHBG (52 ± 3 vs. 33 ± 2 nmol/liter, P < 0.00001) than younger men at baseline. Total and free testosterones increased with TE dose and were higher in older men than young men in the 125-, 300-, and 600-mg dose groups. aMCR-T was lower in older men than young men (1390 ± 69 vs. 1821 ± 102 liter/d, P = 0.006). aMCR-T correlated negatively with age (P = 0.0007), SHBG (P = 0.046), and total testosterone during treatment (P = 0.02) and percent body fat at baseline (P = 0.01) and during treatment (P = 0.004). aMCR-T correlated positively with lean body mass at baseline (P = 0.03) and during treatment (P = 0.01). In multiple regression models, significant predictors of aMCR-T included lean body mass (P = 0.008), percent fat mass (P = 0.009), and SHBG (P = 0.001). Conclusions: Higher testosterone levels in older men receiving TE were associated with an age-related decrease in apparent testosterone metabolic clearance rates. Body composition and SHBG were significant predictors of aMCR-T.


2020 ◽  
Vol 27 (12) ◽  
pp. 1186-1191
Author(s):  
Giuseppe Grande ◽  
Domenico Milardi ◽  
Silvia Baroni ◽  
Andrea Urbani ◽  
Alfredo Pontecorvi

Male hypogonadism is “a clinical syndrome that results from failure of the testis to produce physiological concentrations of testosterone and/or a normal number of spermatozoa due to pathology at one or more levels of the hypothalamic– pituitary–testicular axis”. The diagnostic protocol of male hypogonadism includes accurate medical history, physical exam, as well as hormone assays and instrumental evaluation. Basal hormonal evaluation of serum testosterone, LH, and FSH is important in the evaluation of diseases of the hypothalamus-pituitary-testis axis. Total testosterone levels < 8 nmol/l profoundly suggest the diagnosis of hypogonadism. An inadequate androgen status is moreover possible if the total testosterone levels are 8-12 nmol/L. In this “grey zone” the diagnosis of hypogonadism is debated and the appropriateness for treating these patients with testosterone should be fostered by symptoms, although often non-specific. Up to now, no markers of androgen tissue action can be used in clinical practice. The identification of markers of androgens action might be useful in supporting diagnosis, Testosterone Replacement Treatment (TRT) and clinical follow-up. The aim of this review is to analyze the main findings of recent studies in the field of discovering putative diagnostic markers of male hypogonadism in seminal plasma by proteomic techniques. The identified proteins might represent a “molecular androtest” useful as a seminal fingerprint of male hypogonadism, for the diagnosis of patients with moderate grades of testosterone reduction and in the follow-up of testosterone replacement treatment.


1999 ◽  
Vol 87 (6) ◽  
pp. 2274-2283 ◽  
Author(s):  
Gregory A. Brown ◽  
Matthew D. Vukovich ◽  
Rick L. Sharp ◽  
Tracy A. Reifenrath ◽  
Kerry A. Parsons ◽  
...  

This study examined the effects of acute dehydroepiandrosterone (DHEA) ingestion on serum steroid hormones and the effect of chronic DHEA intake on the adaptations to resistance training. In 10 young men (23 ± 4 yr old), ingestion of 50 mg of DHEA increased serum androstenedione concentrations 150% within 60 min ( P < 0.05) but did not affect serum testosterone and estrogen concentrations. An additional 19 men (23 ± 1 yr old) participated in an 8-wk whole body resistance-training program and ingested DHEA (150 mg/day, n = 9) or placebo ( n = 10) during weeks 1, 2, 4, 5, 7, and 8. Serum androstenedione concentrations were significantly ( P < 0.05) increased in the DHEA-treated group after 2 and 5 wk. Serum concentrations of free and total testosterone, estrone, estradiol, estriol, lipids, and liver transaminases were unaffected by supplementation and training, while strength and lean body mass increased significantly and similarly ( P < 0.05) in the men treated with placebo and DHEA. These results suggest that DHEA ingestion does not enhance serum testosterone concentrations or adaptations associated with resistance training in young men.


2015 ◽  
Vol 87 (3) ◽  
pp. 194 ◽  
Author(s):  
Mehmet Zeynel Keskin ◽  
Salih Budak ◽  
Tuǧba Zeyrek ◽  
Orçun Çelik ◽  
Oguz Mertoglu ◽  
...  

Objective: The aim of this study was to investigate the effect of serum gonadotropin and total testosterone levels on semen parameters. Materials and Methods: Three hundred and eighty-two patients that applied to a male infertility polyclinic were included in our study. Serum gonadotropin and total testosterone levels and semen parameters of the patients were analyzed during the first visit to the clinic. The reference FSH value was 1.5-12.4 mIU/mL, that of LH was 1.7-8.6 mIU/mL and the reference value for total testosterone was 249-836 ng/dL. Results: While there was no statistically significant difference between the patients with low gonadotropin levels and the controls regarding any of the semen parameters (p &gt; 0.05), there was a strong statistically significant difference between the patients with high gonadotropin levels and the controls regarding sperm concentration (p = 0.000), total motility (p = 0.000), progressive motility (p = 0.000), and morphology (p = 0.000). There was a strong statistically significant difference between the patients with low testosterone levels and the controls regarding total motility (p = 0.012) and progressive motility (p = 0.010), and a weak statistically significant difference in morphology (p = 0.042). There was no statistically significant difference in semen volume or sperm concentration (p &gt; 0.05). There was no statistically significant difference in any of the semen parameters between the patients with high testosterone levels and the controls (p &gt; 0.05). Conclusions: Our findings especially regarding LH and T levels are not in agreement with previous reports. In this regard, there is a need for larger-scale and randomized trials to resolve this discrepancy.


2014 ◽  
Vol 20 (12) ◽  
pp. 1584-1592 ◽  
Author(s):  
R Bove ◽  
A Musallam ◽  
BC Healy ◽  
K Raghavan ◽  
BI Glanz ◽  
...  

Background: Gonadal steroids may modulate disease course in multiple sclerosis (MS). Objective: To assess the prevalence and clinical associations of hypogonadism in men with MS. Methods: Male patients, aged 18–65 years, with relapsing–remitting MS (RRMS) or clinically-isolated syndrome (CIS) and their first symptom < 10 years prior were selected from a longitudinal clinical study. We measured their hormones in stored morning blood samples, and collected their Expanded Disability Status Scale (EDSS) scores every 6 months and their Symbol Digit Modalities Test (SDMT) results annually. Results: Our analysis included 96 men with a mean age of 40 years, EDSS of 1.1 and disease duration of 4.6 years. Of these men, 39% were hypogonadal (total testosterone < 288 ng/dL); none showed compensatory elevations in luteinizing hormone. Their low testosterone levels and testosterone:estradiol ratios were negatively correlated with body mass index (BMI) and leptin, and showed no correlation with 25-hydroxy-vitamin D levels. In our primary cross-sectional analyses, there was a negative age-adjusted correlation between total testosterone and EDSS ( p = 0.044). In the age-adjusted longitudinal analyses, higher baseline testosterone levels were associated with less decline in SDMT ( p = 0.012). Conclusions: Men with MS may experience hypogonadotropic hypogonadism. Low testosterone levels may be associated with worse clinical outcomes. A potential neuroprotective role for testosterone warrants further investigation.


Author(s):  
Volodymyr Pankiv ◽  
Tetyana Yuzvenko ◽  
Nazarii Kobyliak ◽  
Ivan Pankiv

Background: In men with low levels of testosterone in the blood, it is believed that the symptoms can be regarded as an association between testosterone deficiency syndrome and related comorbidities. Aim: to investigate the effectiveness of testosterone therapy in patients with type 2 diabetes (T2D) and androgen deficiency. Materials and methods: Testosterone replacement therapy was carried out in 26 men with T2D and clinically or laboratory-confirmed androgen deficiency. The age of the subjects ranged from 35 to 69 years old. Laboratory studies included determinations of the concentration of the hormones estradiol, luteinizing hormone (LH), and prostate-specific antigen (PSA). The observation period was 9 months. Results: The average level of total blood testosterone in the subjects before treatment was 9.4 mol/l and was likely lower than that of the control group (19.3 ± 1.6 nmol/l). The levels of total testosterone in the subjects ranged from 3.9 nmol/l to 10.7 nmol/l, and hormone levels measuring less than 8.0 nmol/l were observed in only 11 patients. After a course of testosterone replacement therapy, a stabilization in total testosterone levels at the level of reference values (as compared to the start of treatment) was observed in the blood of men with T2D after 9 months of observation and the administration of the fourth injection (16.83 ± 0.75 nmol/l). Conclusion: The use of long-acting injectable testosterone undecanoate leads to normalization of total testosterone levels in the blood of men with T2D and androgen deficiency, and LH levels in these patients are unlikely to change.


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