Standardising the biochemical confirmation of adult male hypogonadism: A joint position statement by the Society for Endocrinology and Association of Clinical Biochemistry and Laboratory Medicine.

BACKGROUND: Inter-assay variation between different immunoassays and different mass spectrometry methods hampers the biochemical confirmation of male hypogonadism. Furthermore, some laboratories utilise assay manufacturer reference ranges that do not necessarily mirror assay performance characteristics, with the lower limit of normality ranging from 4.9 nmol/L to 11 nmol/L. The quality of the normative data underlying commercial immunoassay reference ranges is uncertain. DESIGN: A working group reviewed published evidence and agreed upon standardised reporting guidance to augment total testosterone reports. RESULTS: Evidence-based guidance on appropriate blood sampling, clinical action limits, and other major factors likely to affect the interpretation of results are provided. CONCLUSIONS: This article aims to improve the quality of the interpretation of testosterone results by non-specialist clinicians. It also discusses approaches for assay harmonisation which have been successful in some but not all healthcare systems.

Standardising the biochemical confirmation of adult male hypogonadism; a joint position statement by the Society for Endocrinology and Association of Clinical Biochemistry and Laboratory Medicine.

Background: Inter-assay variation between different immunoassays and different mass spectrometry methods hampers the biochemical confirmation of male hypogonadism. Furthermore, some laboratories utilis eassay manufacturer reference ranges that do not necessarily mirror assay performance characteristics, with the lower limit of normality ranging from 4.9 nmol/L to 11 nmol/L. The quality of the normative data underlying commercial immunoassay reference ranges is uncertain.Design: A working group reviewed published evidence and agreed upon standardised reporting guidance to augment total testosterone reports. Results: Evidence-based guidance on appropriate blood sampling, clinical action limits, and other major factors likely to affect the interpretation of results are provided. Conclusions: This article aims to improve the quality of the interpretation of testosterone results by non-specialist clinicians. It also discusses approaches for assay harmonisation which have been successful in some but not all healthcare systems.

Androgens and coronary artery disease.

A significant and independent association between endogenous testosterone (T) levels and coronary events in men and women has not been confirmed in large prospective studies, although cross-sectional data have suggested coronary heart disease can be associated with low T in men. Hypoandrogenemia in men and hyperandrogenemia in women are associated with visceral obesity; insulin resistance; low high-density lipoprotein (HDL) cholesterol (HDL-C); and elevated triglycerides, low-density lipoprotein cholesterol, and plasminogen activator type 1. These gender differences and confounders render the precise role of endogenous T in atherosclerosis unclear. Observational studies do not support the hypothesis that dehydroepiandrosterone sulfate deficiency is a risk factor for coronary artery disease. The effects of exogenous T on cardiovascular mortality or morbidity have not been extensively investigated in prospective controlled studies; preliminary data suggest there may be short-term improvements in electrocardiographic changes in men with coronary artery disease. In the majority of animal experiments, exogenous T exerts either neutral or beneficial effects on the development of atherosclerosis. Exogenous androgens induce both apparently beneficial and deleterious effects on cardiovascular risk factors by decreasing serum levels of HDL-C, plasminogen activator type 1 (apparently deleterious), lipoprotein (a), fibrinogen, insulin, leptin, and visceral fat mass (apparently beneficial) in men as well as women. However, androgen-induced declines in circulating HDL-C should not automatically be assumed to be proatherogenic, because these declines may instead reflect accelerated reverse cholesterol transport. Supraphysiological concentrations of T stimulate vasorelaxation; but at physiological concentrations, beneficial, neutral, and detrimental effects on vascular reactivity have been observed. T exerts proatherogenic effects on macrophage function by facilitating the uptake of modified lipoproteins and an antiatherogenic effect by stimulating efflux of cellular cholesterol to HDL. In conclusion, the inconsistent data, which can only be partly explained by differences in dose and source of androgens, militate against a meaningful assessment of the net effect of T on atherosclerosis. Based on current evidence, the therapeutic use of T in men need not be restricted by concerns regarding cardiovascular side effects. Available data also do not justify the uncontrolled use of T or dehydroepiandrosterone for the prevention or treatment of coronary heart disease.

Testosterone and atherosclerosis.

Hypoandrogenemia in men and hyperandrogenemia in women are associated with increased risk of coronary artery disease but also with visceral obesity, insulin resistance, low high-density lipoprotein (HDL) cholesterol, elevated triglycerides, low-density lipoprotein (LDL) cholesterol and plasminogen activator inhibitor (PAI-1). These gender differences and confounders render the precise role of endogenous androgens in atherosclerosis unclear. Exogenous androgens, on the other hand, induce both apparently beneficial and deleterious effects on cardiovascular risk factors by decreasing serum levels of HDL-C, PAI-1 (apparently deleterious), Lp(a), fibrinogen, insulin, leptin and visceral fat mass (apparently beneficial) in men as well as women. However, androgen-induced declines in circulating HDL-C should not automatically be assumed to be pro-atherogenic, since it may reflect accelerated reverse cholesterol transport instead.Short-term application of supraphysiological doses of exogenous T can reduce the severity and frequency of angina pectoris and improve the electrocardiographic signs of myocardial ischaemia; long-term effects have not been investigated. Nonetheless, interpretations of the effects of pharmacological doses of androgens on arterial compliance and flow-mediated dilatation in particular must be treated with circumspection also because at physiological concentrations, beneficial, neutral, and detrimental effects on vascular reactivity can be observed.Testosterone exerts 'pro-atherogenic' effects on macrophage function by facilitating the uptake of modified lipoproteins and an 'anti-atherogenic' effect by stimulating efflux of cellular cholesterol to HDL. In the majority of animal experiments, exogenous testosterone exerted neutral or beneficial effects on the development of atherosclerosis. In conclusion, the overall effect of administration of testosterone on cardiovascular-disease risk is difficult to assess because androgens have such an extraordinary array of effects in vivo. When dealing with a complex multifactorial condition such as CAD, it is premature to assume that clinical benefits can be derived from manipulation of the sex steroid milieu - even when these assumptions are based on biologically plausible mechanisms or, indeed, on cross-sectional risk-factor observational data. Neither needs the therapeutic use of testosterone in men be restricted by concerns regarding cardiovascular side effects.