Salivary Testosterone in Men: Diurnal Variation and Post-Prandial Responses

Study Overview
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Brief Summary
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The purpose is to evaluate Sal-T against standard biomarkers of male gonadal status based on serum T, calculated free T and BAT. The optimal salivary sampling in terms of fasting and time of day will also be defined. The ultimate aim is to add Sal-T into the Trust's repertoire of tests in investigating suspected hypogonadism in men.

Detailed Description
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To investigate whether salivary (free) testosterone is subject to similar prandial variations reported for serum total testosterone. Study 1: Assessment of diurnal variation in salivary testosterone adjusted for prandial state in 20 healthy men. Study 2: Measurement of salivary and serum testosterone and related biomarkers before and after a standard 75g oral glucose load in 40 men.

Official Title
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Salivary Testosterone in Men: Diurnal Variation and Post-prandial Responses

Conditions
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Hypogonadism, Male

Intervention / Treatment
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* Other: Testosterone Measurements in healthy volunteers after fasting
* Other: Testosterone Measurements after glucose loading


Participation Criteria
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Eligibility Criteria
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For 1st part of study -volunteers: Inclusion Criteria: Aged 20-60 years Male Exclusion Criteria: Subjects with learning disability or those lacking mental capacity to give consent. On (prescribed and over-the-counter) medication and herbal remedies known to affect androgen metabolism. Known hypogonadism. Conditions known to affect androgen metabolism, including chronic inflammatory diseases, chronic liver disease, chronic kidney disease and thyroid dysfunction. Any co-morbidity. Periodontal disease. Dental work 48 hours prior to the test. Exercise on the day, prior to and during sampling periods. Brushed teeth within 1hr prior to sample collection. Obesity defined as a body mass index (BMI) of greater than 29.9 kg/m2As 2nd part of study for glucose load - oral glucose tolerance test (OGTT): Inclusion criteria: Aged over 40-60 years. Attending for routine 75 g OGTT Exclusion criteria: Subjects with learning disability or lacking mental capacity to give consent. On (prescribed and over-the-counter) medication and herbal remedies known to affect androgen metabolism. Known hypogonadism. Conditions known to affect androgen metabolism, including chronic inflammatory diseases, chronic liver disease, chronic kidney disease and thyroid dysfunction. Subjects with difficult venous access. Periodontal disease. Dental work 48 hours prior to the test. Brushed teeth within 1hour prior to sample collection. Exercise on day prior to and during the OGTT.

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 60 Years

Sexes Eligible for Study
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Male

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| diurnal variation assessment<br>Assessment of diurnal variation in salivary testosterone adjusted for prandial state | Other: Testosterone Measurements in healthy volunteers after fasting<br>* salivary testosterone measurements taken in morning and evening and a single blood test for testosterone taken<br>|
| Glucose load measurements<br>Measurement of salivary and serum testosterone and related biomarkers before and after a standard 75g oral glucose load | Other: Testosterone Measurements after glucose loading<br>* salivary tstosterone and blood testosterone measurements<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in salivary testosterone during the day independent of prandial state | testosterone levels | 24 hours | 
| Changes in salivary testosterone following an oral glucose load | testosterone levels | 2 hours |