scholarly journals Validity of free testosterone calculation in pregnant women

2019 ◽  
Vol 8 (6) ◽  
pp. 672-679
Author(s):  
M P Schuijt ◽  
C G J Sweep ◽  
R van der Steen ◽  
A J Olthaar ◽  
N M M L Stikkelbroeck ◽  
...  
Keyword(s):  
Pregnant Women ◽  
Equilibrium Dialysis ◽  
Free Testosterone ◽  
Sex Hormone Binding Globulin ◽  
Total Testosterone ◽  
Testosterone Concentration ◽  
Testosterone Levels ◽  
Liquid Chromatography Tandem Mass ◽  
Highly Correlated ◽  
Design And Methods

Objective Increased maternal testosterone concentration during pregnancy may affect the fetus. Therefore it is clinically relevant to have a quick and reliable method to determine free testosterone levels. Current calculators for free testosterone are suspected to perform poorly during pregnancy due to suggested competition between high levels of estradiol and free (bio-active) testosterone for sex hormone-binding globulin (SHBG) binding. Therefore, it is claimed that reliable calculation of free testosterone concentration is not possible. However, recent evidence on SHBG-binding sites questions the estradiol effect on the testosterone-SHBG binding during pregnancy. In this study, we investigated whether the free testosterone concentration can be calculated in pregnant women. Design and methods Free testosterone was measured with a specially developed equilibrium dialysis method combined with liquid chromatography tandem mass spectrometry (LC-MS/MS). Free testosterone was also calculated with the formulas of Vermeulen et al. and Ross et al. Results Total and free testosterone measured in healthy men and women were in good agreement with earlier reports. In pregnant women, total testosterone values were higher than in non-pregnant women, whereas free testosterone values were comparable. Calculated free testosterone levels in pregnant women were highly correlated, but marginally higher, compared to measured free testosterone levels. Conclusions We developed an equilibrium dialysis–LC-MS/MS method for the measurement of free testosterone in the low range of pregnant and non-pregnant women. Although during pregnancy total testosterone is increased, this is not the case for free testosterone. The free testosterone formulas perform well in pregnant women.

scholarly journals In men older than 70 years, total testosterone remains stable while free testosterone declines with age. The Health in Men Study

2007 ◽  
Vol 156 (5) ◽  
pp. 585-594 ◽  
Author(s):  
Bu B Yeap ◽  
Osvaldo P Almeida ◽  
Zoë Hyde ◽  
Paul E Norman ◽  
S A Paul Chubb ◽  
...  
Keyword(s):  
Free Testosterone ◽  
Older Men ◽  
Early Morning ◽  
Sex Hormone Binding Globulin ◽  
Total Testosterone ◽  
Limited Data ◽  
Cross Sectional ◽  
Testosterone Concentration ◽  
Age Related ◽  
Clinical Consequences

Objective: An age-related decline in serum total and free testosterone concentration may contribute to ill health in men, but limited data are available for men > 70 years of age. We sought to determine the distribution and associations of reduced testosterone concentrations in older men. Design: The Health in Men Study is a community-representative prospective cohort investigation of 4263 men aged ≥ 70 years. Cross-sectional hormone data from 3645 men were analysed. Methods: Early morning sera were assayed for total testosterone, sex hormone binding globulin (SHBG) and LH. Free testosterone was calculated using the Vermeulen method. Results: Mean (± s.d.) serum total testosterone was 15.4 ± 5.6 nmol/l (444 ± 162 ng/dl), SHBG 42.4 ± 16.7 nmol/l and free testosterone 278 ± 96 pmol/l (8.01 ± 2.78 ng/dl). Total testosterone correlated with SHBG (Spearman’s r = 0.6, P < 0.0001). LH and SHBG increased with age (r = 0.2, P < 0.0001 for both). Instead of declining, total testosterone increased marginally (r = 0.04, P = 0.007) whilst free testosterone declined with age (r = −0.1, P < 0.0001). Free testosterone was inversely correlated with LH (r = −0.1, P < 0.0001). In multivariate analyses, increasing age, body mass index (BMI) and LH were associated with lower free testosterone. Conclusions: In men aged 70–89 years, modulation of androgen action may occur via an age-related increase in SHBG and reduction in free testosterone without a decline in total testosterone concentration. Increasing age, BMI and LH are independently associated with lower free testosterone. Further investigation would be required to assess the clinical consequences of low serum free testosterone, particularly in older men in whom total testosterone may be preserved.

scholarly journals The analog free testosterone assay: are the results in men clinically useful?

1998 ◽  
Vol 44 (10) ◽  
pp. 2178-2182 ◽  
Author(s):  
Stephen J Winters ◽  
David E Kelley ◽  
Bret Goodpaster
Keyword(s):  
Free Testosterone ◽  
Sex Hormone Binding Globulin ◽  
Total Testosterone ◽  
Serum Concentrations ◽  
Testosterone Concentration ◽  
Low Testosterone ◽  
Relationship Of ◽  
The Relationship ◽  
Constant Percentage

Abstract Men with low testosterone concentrations are usually hypogonadal. However, because variations in the testosterone transport protein, sex hormone-binding globulin (SHBG), directly influence the total testosterone concentration, confirmation of a low testosterone with a measurement of free testosterone or “bioavailable” testosterone (BAT) is recommended. In the present study, we examined the relationship of SHBG with free testosterone (Coat-A-Count assay, Diagnostic Products) and with BAT in men (n = 29) and women (n = 28) who participated in a study of the metabolic determinants of body composition. As expected, total testosterone was strongly positively correlated with SHBG among men (r = 0.68; P &lt;0.01). Although the BAT was independent of SHBG in men (r = 0.02), SHBG was an important predictor of free testosterone (r = 0. 62; P &lt;0.01). In contrast, in women serum concentrations of total testosterone (r = −0.26; P = 0.17), free testosterone (r = −0.30; P = 0.17), and BAT (r = −0.46; P = 0.013) all tended to be lower with increasing SHBG. Free testosterone was nearly perfectly positively correlated with total testosterone (r = 0.97) in men, among whom free testosterone represented a relatively constant percentage of the total testosterone (0.5–0.65%), and the percentage of free testosterone was unrelated to SHBG. Thus the Coat-A-Count free testosterone concentration in men, like the total testosterone concentration, is determined in part by plasma SHBG. Accordingly, androgen deficiency may be misclassified with this assay in men with low SHBG. Moreover, the previous findings of reduced free testosterone concentrations with hypertension or hyperinsulinemia or as a risk factor for developing type 2 diabetes, conditions in which SHBG is reduced, may have been methodology-related.

scholarly journals Hypoactive sexual desire in transsexual women: prevalence and association with testosterone levels

2008 ◽  
Vol 158 (3) ◽  
pp. 393-399 ◽  
Author(s):  
Els Elaut ◽  
Griet De Cuypere ◽  
Petra De Sutter ◽  
Luk Gijs ◽  
Michael Van Trotsenburg ◽  
...  
Keyword(s):  
Sexual Desire ◽  
Free Testosterone ◽  
Serum Levels ◽  
Cross Sectional Study ◽  
Sex Hormone Binding Globulin ◽  
Control Group ◽  
Total Testosterone ◽  
Cross Sectional ◽  
Oestrogen Treatment ◽  
Testosterone Levels

ObjectiveAn unknown proportion of transsexual women (defined as post-operative male-to-female transsexuals on oestrogen replacement) experience hypoactive sexual desire disorder (HSDD). It has been suggested that the absence of ovarian androgen production together with oestrogen treatment-related increase in sex hormone-binding globulin (SHBG) levels could be leading to HSDD, due to low levels of biologically available testosterone. This study wishes to document the HSDD prevalence among transsexual women and the possible association to androgen levels.DesignCross-sectional study.MethodsTranssexual women (n=62) and a control group of ovulating women (n=30) participated in this study. Questionnaires measuring sexual desire (sexual desire inventory) and relationship and sexual satisfaction (Maudsley Marital Questionnaire) were completed. Serum levels of total testosterone, LH and SHBG were measured in blood samples obtained at random in transsexual women and in the early follicular phase in ovulating women.ResultsThe transsexual group had lower levels of total and calculated free testosterone (both P<0.001) than the ovulating women. HSDD was reported in 34% of the transsexual and 23% of the ovulating women (P=0.30). Both groups reported similar levels of sexual desire (P=0.97). For transsexual women, no significant correlation was found between sexual desire and total (P=0.64) or free testosterone (P=0.82). In ovulating women, these correlations were significant (P=0.006, resp. P=0.003).ConclusionsHSDD is reported in one-third of transsexual women. This prevalence is not substantially different from controls, despite markedly lower (free) testosterone levels, which argues against a major role of testosterone in this specific group.

scholarly journals Testosterone profile in older men with Alzheimer's disease

2008 ◽  
Vol 2 (4) ◽  
pp. 289-293
Author(s):  
Cristiana Roscito Arenella Dusi ◽  
Lílian Schafirovits Morillo ◽  
Regina Miksian Magaldi ◽  
Adriana Nunes Machado ◽  
Sami Liberman ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Free Testosterone ◽  
Older Men ◽  
Sex Hormone Binding Globulin ◽  
Control Group ◽  
Total Testosterone ◽  
Chi Square ◽  
Testosterone Levels ◽  
Significant Difference

Abstract Evidence suggests low testosterone levels in Alzheimer's disease. Objectives: To compare testosterone levels between older men with and without Alzheimer's disease. Methods: Fourteen men with Alzheimer's disease were compared with twenty eight men without dementia. Demographic variables and clinical profiles were analyzed. Within fifteen days before or after the described evaluation, measures of total testosterone and Sex Hormone Binding Globulin (SHBG) were performed. Free testosterone level was calculated based on total testosterone and SHBG. Quantitative variables were analyzed using Student's t test or Kruskal-Wallis test, while qualitative variables were analyzed using chi-square or Fisher test. Results: Mean age in the Control and Alzheimer's disease groups were 72.0 (SD±4.8) years and 79.3(SD±5.9) years, respectively (p=0.001). Mean schooling between these two groups were 8.78 and (±5.86) years, respectively (p=0.022). There were no statistically significant differences between the two groups for testosterone levels, although a trend was observed for the Alzheimer's disease group to present lower levels than the control group (p=0.066). There was no direct correlation between free testosterone and age, although a trend was evident (p=0.068). Conclusions: There was no significant difference in testosterone between men with AD and those without dementia.

scholarly journals Effects of SHBG rs1799941 Polymorphism on Free Testosterone Levels and Hypogonadism Risk in Young Non-Diabetic Obese Males

2019 ◽  
Vol 8 (8) ◽  
pp. 1136
Author(s):  
Daniel Castellano-Castillo ◽  
José Luis Royo ◽  
Ana Martínez-Escribano ◽  
Lidia Sánchez-Alcoholado ◽  
María Molina-Vega ◽  
...  
Keyword(s):  
Regression Models ◽  
Biological Function ◽  
Free Testosterone ◽  
Sex Hormone ◽  
Sex Hormone Binding Globulin ◽  
Total Testosterone ◽  
Hormone Binding ◽  
Testosterone Levels ◽  
Increased Risk ◽  
Lineal Regression

Introduction: Obesity has been associated with increased risk of presenting hypogonadism. Free testosterone (FT) is the fraction of testosterone that carries out the biological function of testosterone, and is determined from total testosterone (TT) and sex-hormone binding globulin (SHBG) levels. We aimed to study the SHBG polymorphism rs1799941 in a cohort of young non-diabetic obese males to unravel the possible implication of this polymorphism in obesity-related hypogonadism. Methodology: 212 young (<45 years) non-diabetic obese (BMI ≥ 30 kg/m2) males participated in this study. Subjects were classified according to TT and FT levels in: Eugonadal (n = 55, TT > 3.5 ng/mL and FT ≥ 70 pg/mL; EuG), normal FT hypogonadism (n = 40, TT < 3.5 and FT ≥ 70 pg/mL; normal FT HG) and hypogonadism (n = 117, TT < 3.5 ng/mL and TL < 70 pg/mL; HG). The SHBG rs1799941 polymorphism (GG/GA/AA) was analyzed using the Taqman Open Array (Applied biosystem). Results: The rs1799941 frequencies were different among the groups. Higher proportion of the allele (A) was found in HG, compared to EuG and normal FT HG. Among the genotypes, the rare homozygous (AA) were found in the normal FT HG group and higher levels of serum SHBG and lower of FT were observed. The presence of the allele A was related (according to lineal regression models) to an increased of SHBG levels ((GA) β = 3.28; (AA) β = 12.45) and a decreased of FT levels ((GA) β = −9.19; (AA) β = −18.52). The presence of the allele (A) increased the risk of presenting HG compared to normal FT HG (OR = 2.54). Conclusions: The rs1799941 of the SHBG gene can partially determine the presence of obesity-related hypogonadism in young non-diabetic males and whether these subjects have normal FT HG.

scholarly journals SAT-LB5 Prevalence of Hypogonadism in Young Obese Males

2020 ◽  
Vol 4 (Supplement_1) ◽  
Author(s):  
Anup Halappanavar ◽  
Rajiv Pakhetra
Keyword(s):  
Hypogonadotropic Hypogonadism ◽  
Armed Forces ◽  
Free Testosterone ◽  
Sex Hormone Binding Globulin ◽  
P Value ◽  
Total Testosterone ◽  
Reference Ranges ◽  
Cross Sectional ◽  
Testosterone Levels ◽  
The Impact

Abstract Ageing, obesity, and chronic illness are major factors affecting serum testosterone (T) levels in men.The magnitude of the impact of ageing on serum T levels is well established, for obesity this is less clear. Severe obesity may lead to isolated hypogonadotropic hypogonadism (IHH). Several explanations have been offered to clarify the presence of reduced T levels in obese men. One relates to the technique that is generally employed to measure serum androgen levels, i.e. measurement of total testosterone (TT) instead of free testosterone (FT). TT represents the sum of FT and T bound to albumin and sex hormone binding globulin (SHBG). A profound reduction in SHBG level is commonly found in obese men, and this is a major factor causing a decrease in TT.Measurement of free testosterone levels may provide a more accurate assessment of androgen status than the (usually preferred) measurement of total testosterone in situations where SHBG levels are outside the reference range. However, reference ranges for free testosterone levels are not well established, especially in older men, and some have argued that the measurement of free testosterone levels merely reintroduces age in a covert form. This is a cross sectional study to estimate prevalence of hypogonadism in young obese males. In this study 147 young obese men participated, of which we confirmed low total testosterone (TT) levels in 35.37% of subjects with a p value of 0.06. Since only Total Testosterone was measured for categorizing subjects with or without hypogonadism, Free Testosterone measurement would be a better indicator for the diagnosis of hypogonadism as in cases where the total testosterone is borderline-low or when SHBG concentrations are abnormal. As such, the study is valuable in the context of the ongoing controversy as to whether testosterone treatment should be limited to men with classical hypogonadism, or be considered for appropriately selected men with functional hypogonadism as well. The principal findings are in general agreement with existing literature reporting correlation between levels of testosterone, body mass index and constitutional symptoms. However, this has never been shown before in context of Indian population. The present study was carried out at Armed Forces Medical College and Command Hospital, Pune between October 2017 to August 2019.We studied to see if there is association between testosterone levels and BMI. In our study we found no statistical association as the p value was 0.26 (&gt;0.05)

Metabolic clearance rate of testosterone in male epileptic patients on anti-convulsant therapy

1991 ◽  
Vol 129 (3) ◽  
pp. 465-468 ◽  
Author(s):  
M. J. Wheeler ◽  
B. K. Toone ◽  
A. Dannatt ◽  
P. B. C. Fenwick ◽  
S. Brown
Keyword(s):  
Clearance Rate ◽  
Patient Population ◽  
Free Testosterone ◽  
Sex Hormone Binding Globulin ◽  
Total Testosterone ◽  
Metabolic Clearance ◽  
Metabolic Clearance Rate ◽  
Testosterone Concentration ◽  
The Mean ◽  
Low Testosterone

ABSTRACT There are several reports which state that male epileptics on anti-convulsant therapy have reduced sexual activity. We and others have shown that, although total testosterone is raised, the free testosterone concentration is reduced in this patient population. This could be a result of an increased metabolic clearance rate (MCR) of testosterone, inadequate secretion of LH to stimulate testosterone synthesis or inappropriately low testosterone production by the Leydig cells. We have examined these possibilities by measuring the MCR of testosterone in 15 male epileptics on anti-convulsant therapy. In this group of patients, the mean LH (9·3±5·9 IU/l) and sex-hormone binding globulin (SHBG) (54·5±22·9 nmol/l) concentrations were significantly greater than those of five normal control subjects (4·7±1·11 IU/l and 26·0 ±7·0 nmol/l respectively). Mean total testosterone concentrations of the two groups were not significantly different but the mean percentage of free testosterone and free testosterone concentration were significantly lower in the patient population (2·06±0·43 vs 2·98±0·27 and 0·56±1·1 vs 0·79±0·7 pmol/l). The MCR of testosterone was significantly lower in the patients (773±322 vs 1354±443 1/day) and showed a positive correlation with the percentage of free testosterone. Therefore, our results suggest that the lowered free testosterone in male epileptics on anti-convulsant therapy is not due to an increased MCR of testosterone. The increased LH concentration suggests primary hypogonadism. This, in turn, could be responsible for low free testosterone levels in the presence of normal testosterone. Journal of Endocrinology (1991) 129, 465–468

Decrease in serum testosterone concentration during treatment with tetracycline

1983 ◽  
Vol 103 (2) ◽  
pp. 269-272 ◽  
Author(s):  
M. O. Pulkkinen ◽  
J. Mäenpää
Keyword(s):  
Binding Capacity ◽  
Serum Testosterone ◽  
Free Testosterone ◽  
Sex Hormone Binding Globulin ◽  
Total Testosterone ◽  
Serum Concentrations ◽  
Hormone Binding ◽  
Testosterone Concentration ◽  
Tetracycline Treatment ◽  
Cessation Of Treatment

Abstract. Serum concentrations of testosterone and the binding capacity of sex hormone binding globulin (SHBG) were measured on 2 days immediately preceding tetracycline treatment, on 3 days of treatment and on 2 days immediately after cessation of treatment. On the treatment days serum mean testosterone concentrations were significantly lower than on the control days (17 ± 0.9 vs 21 ± 0.8 nmol/l, P < 0.01). There were no differences in the SHBG. The 'free testosterone index' behaved like the total testosterone.

In women, no significant variances of calculated free testosterone (cFT) are observed when a fixed value of albumin (Alb: 4.3 g/dL) is used instead of measured albumin values

2014 ◽  
Vol 20 (3) ◽  
Author(s):  
Dinamarie Garcia-Banigan ◽  
Andre Guay ◽  
Abdul Traish ◽  
Gheorghe Doros ◽  
John Gawoski
Keyword(s):  
Equilibrium Dialysis ◽  
Free Testosterone ◽  
Sex Hormone Binding Globulin ◽  
Total Testosterone ◽  
Hormone Binding ◽  
R Software ◽  
Significant Variance ◽  
Clinical Evaluations ◽  
Data Points ◽  
Two Measures

AbstractCalculated free testosterone (cFT) is determined from the values of total testosterone (TT), sex hormone binding globulin (SHBG), and albumin (Alb) using mathematical formulae. We evaluated any potential cFT variance when determined with fixed Alb (4.3 g/dL) compared to measured Alb, and the point at which low SHBG and Alb combinations produced significant cFT variance.We analyzed 2050 data points in 1222 women. cFT values with fixed vs. the actual measured Alb values were evaluated and contrasted. cFT levels were determined theoretically for all possible combinations of TT, SHBG, and Alb.Agreement between the two measures was assessed with Lin’s concordance coefficient. Statistical analyses were performed using R software version 2.12.1.Mean Alb was 4.05±0.30 g/dL. Mean SHBG 73.0±53.3 nmol/L. A fixed Alb of 4.3 g/dL produced no significant variance for most evaluations of cFT. The accuracy decreased with Alb ≤3.5 g/dL in combination with SHBG ≤30 nmol/L and exists in 1.0% of the samples.A fixed Alb of 4.3 g/dL is acceptable for most clinical evaluations. If Alb is ≤3.5 g/dL, along with SHBG ≤30 nmol/L, the variance increases and a free testosterone (FT) measurement by equilibrium dialysis is warranted for better accuracy.

scholarly journals Features of hyperandrogenism in men

2021 ◽  
Vol 67 (2) ◽  
pp. 111-115
Author(s):  
V. A. Filatova ◽  
R. V. Rozhivanov
Keyword(s):  
Young Patients ◽  
Clinical Manifestations ◽  
Free Testosterone ◽  
Sex Hormone Binding Globulin ◽  
P Value ◽  
Total Testosterone ◽  
Androgenic Alopecia ◽  
Testosterone Levels ◽  
Group 3 ◽  
Group 2

BACKGROUND: Today the problem of hyperandrogenism in women is a widely studied and discussed while same issue in relation to men is barely raised. In clinical practice, hyperandrogenism can be the cause of a number of diseases.AIM: Provide characterization the variations of physiological hyperandrogenism in men.MATERIALS AND METHODS: Сontinuous cross-sectional study of 100 men with hyperandrogenism. The study assessed the volume and structure of the prostate, the volume of the testicles; the levels of luteinizing hormone (LH), total testosterone, sex hormone binding globulin (SHBG) were determined with further calculation of the level of free testosterone according to Vermeullen, and dihydrotestosterone (DHT). Based on the results of the analysis of the hormonal status of patients with hyperandrogenism, 4 groups of patients were formed: 1-patients with increased total testosterone and SHBG levels; 2-patients with elevated total testosterone levels and normal SHBG levels; 3-patients with an increased level of total testosterone, DHT with a normal level of SHBG; 4-patients with an increased level of DHT with normal levels of total testosterone and SHBG. The difference between groups of patients was determined, a p-value <0.05 was considered statistically significant.RESULTS: The age and volume of the prostate in group 1 patients were statistically significantly higher than in the other groups. This group, despite the high level of total testosterone, was not characterized by complaints of acne. Group 2 patients complained of acne more often, but the prevalence of this symptom even in this group was statistically significantly lower than in group 3 patients. At the same time, the frequency of occurrence of alopecia was statistically significantly lower in group 2 than in patients of both groups 3 and 4. Patients of group 3 had the most striking clinical manifestations of hyperandrogenism. Group 4 was characterized by alopecia.CONCLUSION: An increase of androgen levels can be detected at any age. At the same time, in men of the older age group, an increase in the level of total testosterone may be due to an increase in the secretion of SHBG and not be accompanied by an increase in the level of free testosterone. In young patients, the clinical manifestations of hyperandrogenism may differ: patients with elevated DHT levels are characterized by androgenic alopecia; acne is common in men with elevated total and free testosterone levels, and increased DHT exacerbates the problem.

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