Diagnostic of andropause: a problem not yet solved

Abstract

A ndropause, also known as late-onset hypogonadism (LOH) or hypogonadism in aging males, is due to alterations in the testicular and hypothalamic-pituitary functions (1). A reduction in both the hormone production by the Leydig cells and in the GnRH secretion by the hypothalamus takes place, leading to inadequate secretion of LH by the pituitary (1). Some elders, however, have normal LH levels in the presence of hypogonadism and its increase is not required for the LOH diagnosis (2). The androgen deficiency in elderly males is normally partial and only a few of them clearly display hormonal levels under the lower limit for young and healthy males, which makes the hypogonadism diagnosis harder in such cases (1).In this issue of ABE&M, two articles from Clapauch e cols. (3,4) evaluate the diagnosis of hypogonadism associated to the age in two group of men, with or without osteoporosis. In one of the articles, the total testosterone (TT), calculated free testosterone (cFT), and calculated bioavailable testosterone (cBT) dosages were evaluated (3) and in the other article the relation of those testosterone dosages with three acknowledged questionnaires of the gonadal function evaluation were also analyzed (4).The decrease of free and total serum testosterone levels is gradual and progresses with age. The total testosterone level remains constant up to the age of 50 to 55 and after that, a progressive decrease takes place (5,6), as confi rmed by Clapauch e cols. (3). Free testosterone and albumin-bound testosterone, which represents the bioavailable testosterone, progressively decrease at the ages of 25 to 75 years, due to the continuous increase of SHBG with age (5,6) However, the hypogonadism diagnosis by evaluation of testosterone dosages in blood is not reliable because the procedure may present technical laboratorial diffi culties. In the same city there may be clinical laboratories using different methods and normal ranges for testosterone analysis, and that makes each lab responsible to improve its own reference values by themselves (2). In addition to that, weekly variations in the testosterone dosage may occur in elderly men whose testosterone levels vary around the lower limits (1,2), leading to the necessity of at least two dosages in different days, in order to determine hypogonadism with a reliable laboratorial parameter which was also demonstrated by Clapauch e cols. (3).The signs and symptoms of androgen defi ciency are not specifi c and they can change with age, associated diseases, severity and duration of the androgen defi ciency, variation of the androgenic sensitivity and previous testosterone therapy (1). Moreover, the testosterone level threshold under which adverse effects and the onset of androgenic defi ciency symptoms are associated is not known (1). For instance, Clapauch e cols. (4) found that total scores equal to or higher than 27 in the Aging Male's Symptoms Scale (AMS) questionnaire were only related to TT levels below 400 ng/dL and no association was found in cBT or cFT.

The Effects of Aging on Testicular Volume and Glucose Metabolism: an Investigation with Ultrasonography and FDG-PET

“…Unlike the cessation of menstruation in female menopause, which is demarcated by an abrupt and symptomatic event, age-related changes in males are manifested generally more subtly and insidiously [7], which is so-called as andropause. The criteria of diagnosis and indication for treatment of andropause remain a clinical dilemma.…”

Prolactinomas Resistant to Treatment With Dopamine Agonists: Long-Term Follow-Up of Six Cases

“…Diagnoses of hormonal deficiencies were made using clinical and laboratory assessments as follows: for basal cortisol, values lower than 6 μg/dL or the use of exogenous corticosteroids for hormone replacement were considered as suggestive of adrenal insufficiency; levels higher than 10 μg/dL were considered as normal, and in cases of basal cortisol between 6 and 10 μg/dL or clinically suspicious of adrenal insufficiency, were submitted to a insulin tolerance test, considered as normal, if levels > 18 μg/dL were achieved ( 21 ); for thyroid function, FT4 values lower than 1.0 ng/mL when hypothyroidism secondary to the hypothalamic-pituitary lesion was suspected ( 22 ), TSH above 10 μUI/mL in cases of primary thyroid insufficiency, or if the patient was on levothyroxine replacement therapy; for testicular deficiency, a total testosterone concentration below 300 ng/dL on two occasions, decreased libido, and erectile dysfunction symptoms or on testosterone replacement ( 23 ); and for ovarian deficiency, estradiol values below the reference values for the menstrual cycle or for menopausal women.…”