When is bioavailable testosterone a redundant test in the diagnosis of hypogonadism in men?

The relationship of salivary testosterone and male sexual dysfunction in opioid-associated androgen deficiency (OPIAD)

BACKGROUND

Opioids are an effective treatment for chronic non-malignant pain (CNP). Long-term use risks and side effects such as opioid-induced androgen deficiency (OPIAD) exist. This could be measured by saliva testosterone (Sal-T).

OBJECTIVES

To evaluate OPIAD in long-term opioid use in CNP patients.

METHODS

A cross-sectional study included CNP male outpatients under opioid treatment. Total-Testosterone (Total-T), Free-Testosterone (Free-T), Bio-Testosterone (Bio-T) and Sal-T were measured. Correlations were calculated by Spearman's rho (SPSS 20).

RESULTS

From 2012 to 2014, 134 from 249 (54%) consecutive male outpatients reported erectile dysfunction (ED), 37% of them related to opioids and 19% evidenced OPIAD. A total of 120 subjects (94 cases and 26 matched-controls) were included. A significantly lower luteinizing hormone, Total-T and Free-T were found, as well as, a significant correlation between Sal-T and Total-T (r = 0.234, p = 0.039), Bio-T (r = 0.241, p = 0.039), IIEF (r = 0.363, p = 0.003) and HAD-anxiety (r = -0.414, p = 0.012) in OPIAD patients. Sal-T levels were significantly lower in patients with severe-moderate ED versus mild ED (p = 0.045) and in patients with severe ED versus moderate-mild ED (p = 0.036).

CONCLUSIONS

These data demonstrate the high prevalence of ED in long-term use of opioids, part of this is associated to OPIAD, which can be tested by Sal-T as a non-invasive approach.

Functional testosterone: biochemical assessment of hypogonadism in men--report from a multidisciplinary workshop hosted by the Ontario Society of Clinical Chemists

OBJECTIVES

In 2004, the Ontario Society of Clinical Chemists (OSCC) held an invitational multidisciplinary workshop to establish the most reliable, cost-effective approach to the biochemical assessment of hypogonadism in men.

METHODS

Specialists across Canada in clinical biochemistry, endocrinology, family medicine and urology were invited to participate in this workshop which included individual presentations and a consensus component addressing two challenge statements: 1) 'Determinations for total testosterone (TT) are equivalent to those for bioavailable testosterone (BAT) or calculated BAT (cBAT) or free testosterone (FT) (by analogue radioimmunoassay or equilibrium dialysis) or calculated FT (cFT)'; 2) 'There is no good evidence that borderline low testosterone concentrations in men should be treated'. The main outcomes were to identify what agreement exists in Canada, what issues were still controversial, and what research remains to be addressed.

RESULTS

Six recommendations based on expert opinion addressed these main themes: investigate with morning total testosterone (TT) followed by repetition and reflexive testing of sex hormone binding globulin (SHBG) if testosterone is 8-15 nmol/L with automatic calculation of cBAT; discontinue the use of analogue free testosterone assays; and definitive methods and standards must be available to ensure standardized results.

CONCLUSIONS

Total testosterone is a reliable marker for the initial investigation of men presenting with symptoms of hypogonadism; cBAT is a reasonable follow-up test in patients with equivocal biochemical or consistent symptomatic findings.

Gonadal impact of target of rapamycin inhibitors (sirolimus and everolimus) in male patients: an overview

The immunosuppressive agents target of rapamycin inhibitors (TOR-I) (sirolimus, and everolimus) have been widely used in kidney transplantation for >10 years. Up to 40% of men receiving a kidney transplant are younger than 50, and fertility as well as erectile function are major concerns. In this review, we provide a synopsis of past studies focusing on gonadal function in men treated with TOR-I, mainly sirolimus, to establish what impact they have on male gonads, and which pathophysiological pathways are involved. A PubMed search for the years 1990-2006 selected articles that focused on the gonadal impact of TOR-I. Primary outcome measures were testosterone, follicle-stimulating hormone (FSH), and luteinizing hormone (LH) levels. Secondary outcome measures were sexual function, fertility status and sperm parameters. Treatment with TOR-I results in a decrease in testosterone level, and an opposite increase in LH. Moreover, spermatogenesis seems to be disrupted by TOR-I and FSH levels are increased. Sirolimus and everolimus inhibit the activity of mammalian targets of rapamycin, a serine/threonine kinase involved in numerous cell-growth processes. Molecular mechanisms of action of TOR-I on the testis involve inhibition of a stem cell factor/c-kit-dependant process in spermatogonia. Preliminary results appear to show that TOR-I treatment has deleterious actions on the testis and impairs gonadal function after renal transplantation, but the impact of these effects are unknown.

Measurement of testosterone and its sub-fractions in Canada

Interest in measuring bioactive testosterone in aging males has increased considerably in the last 5 years in Canada. Emerging andropause clinics have submerged our laboratories with requests for bioavailable testosterone (BAT) testing in replacement or addition to the traditional total testosterone (TT) and direct free testosterone (FT) assays. Beginning with a brief explanation of the bioavailability concept of Pardridge, this review examines the technical characteristics of various approaches currently available to measure TT and its sub-fractions. First, limitations in the measurement of TT, SHBG, and particularly direct (analog) FT assays are extracted from the scientific literature and recent external and internal QC reports. It is concluded that the free direct T assay is useless in the clinical context of andropause. The impact of the observed limitations of TT and SHBG measurements on calculated FT and BAT or BAT obtained by precipitation with ammonium sulfate is then discussed. A comparative evaluation of the advantages and disadvantages of calculated FT or BAT vs. precipitated BAT is presented before concluding that doing a TT as a first line test remains overall the most cost-effective measurement in the diagnosis of hypogonadism in males, and that this sole determination will be sufficient in over 75% of the cases.