Testosterone and its binding in the plasma of male subjects with chronic renal failure

End-stage renal disease in the elderly: dialysis or conservative management?

The challenges of health care in an aging population are mirrored in the field of nephrology, in which an increasing proportion of the population has chronic kidney disease (CKD) and end-stage renal disease requiring dialysis. The need for dialysis negatively influences survival and health-related quality of life (HRQoL) in all age groups, but particularly in the elderly, raising the issue of withholding dialysis and emphasizing conservative management of CKD in some patients. Increased mortality is seen in dialysis patients who are elderly, have significant comorbidities, and have poor functional status. In such patients, the option of palliative care should be discussed in order to focus on HRQoL in the physical, psychological, and social domains. Although survival among the elderly who forgo dialysis is worse than those who begin dialysis, hospitalizations and HRQoL may be better, especially if the CKD-associated complications are appropriately addressed through effective palliative care.

Thyroid hormone abnormalities and frailty in elderly patients with chronic kidney disease: a hypothesis

Thyroid hormones play a crucial role in the metabolic activities of adults, affecting almost every organ system. All types of thyroid diseases are encountered in the elderly. As symptoms and signs of thyroid diseases may overlap with what is considered to be "normal aging," the presence of a thyroid disorder may go undiagnosed in the elderly. This potential problem is further compounded in elderly patients with chronic kidney disease (CKD), where the presence of an underlying hormonal problem such as hypothyroidism may be erroneously attributed to multiple comorbidities, the aging process, or the kidney disease. Frailty is being recognized as a contributing factor to the poor outcomes (hospitalization and high mortality) in elderly patients with CKD. Predisposing factors leading to frailty in elderly with CKD such as increased inflammatory markers, anemia, low testosterone, sarcopenia, and depression are associated with thyroid hormonal abnormalities. These associations are remarkable and raise the question of whether routine monitoring and screening for thyroid hormone changes in elderly CKD patients might be helpful in identifying reversible causes of frailty. In this review, we will focus on the associations between thyroid hormone abnormalities and the predisposing factors of frailty in elderly patients with CKD. If a cause-effect relationship of thyroid hormone abnormalities and factors predisposing to frailty in CKD patients is established, identification and treatment of thyroid abnormalities in this population would assume increased importance.

A review of the effects of growth hormone changes on symptoms of frailty in the elderly with chronic kidney disease

The incidence and prevalence of chronic kidney disease (CKD) is increasing worldwide, especially in the elderly. Recently, functional impairment and frailty have been recognized as factors affecting the quality of life, and outcomes in elderly patients with CKD and therapeutic interventions to improve function and reduce frailty are therefore being considered. Growth hormone (GH) levels decrease with age and GH actions are impaired in CKD patients. GH stimulates protein synthesis, bone, and glucose metabolism, and affects body composition by reducing body fat and increasing lean body mass. An increase in lean body mass may reduce frailty and thus avoid functional impairment. Thus, providing GH to elderly CKD patients could potentially improve outcomes and quality of life by lowering the risk of frailty and associated functional impairment. There are few studies assessing the long-term effects of GH administration on symptoms of frailty in elderly patients with CKD. In this review we will try to shed some light on the trials assessing the administration of GH to elderly subjects and to patients with CKD and focus on the possible role GH administration may play to improve frailty and quality of life in those patients.

Serum levels of testosterone and luteinizing hormone in patients with chronic renal disease

Androgen metabolism has been studied in 33 patients (17 males, 16 females) with chronic renal disease not undergoing dialysis treatment. The mean value of serum testosterone was reduced in both sexes, whereas that of serum leteinizing hormone (LH) was elevated in the males. The parameters became increasingly pathological with decreasing renal function. There was no correlation between serum testosterone and serum LH, indicating an inadequate hypothalamic-pituitary response to the testicular dysfunction. The clinical significance of this relative hypoandrogenaemia is obscure. A possible relation to the anaemia and bone disease of chronic renal failure is discussed.

Puberty in chronic renal failure

Puberty is a period of transition characterized by a sequence of profound physical and psychological changes leading to full sexual maturity. This process is driven and orchestrated by the awakening of the gonadotropic hormone axis. Chronic renal failure and its treatment may interfere with the onset and progress of puberty by numerous mechanisms including endocrine, metabolic and neuropsychological abnormalities, and drug effects. On average, the onset of puberty is delayed by 2 years in children with chronic renal failure, even after successful transplantation. Moreover, pubertal height gain is only 50% of that observed in healthy children. In this report, we discuss the endocrine mechanisms underlying these alterations and highlight new therapeutical options for pubertal growth failure.

Sexual dysfunction in the male dialysis patient: pathogenesis, evaluation, and therapy

Impotence is a common problem in male dialysis patients. Although dialysis patients may appear to have more reasons to be depressed than nondialysis patients, depression has not been found to be correlated with erectile dysfunction in this group. Primary testicular failure is common in male dialysis patients as is hyperprolactinemia. These disorders may be the cause of impotence in some of these patients. An algorithm for the evaluation and treatment of impotence in the male dialysis patient is presented. Successful renal transplantation is associated with improvement in the testicular failure, in the hyperprolactinemia, and in the erectile dysfunction of the male patient with end-stage renal disease.

Hormonal profile and serum zinc levels in uraemic men with gonadal dysfunction undergoing haemodialysis

Serum gonadal hormones, gonadotrophins and zinc levels were studied in thirteen men aged 29-62 yr with chronic renal failure undergoing haemodialysis. All patients had decreased libido and impotence. Serum testosterone levels in patients (18.5 +/- 1.3 (SEM) nmol/l) were significantly lower (p less than 0.05) than in the control group (24.1 +/- 2.2 (SEM) nmol/l) although salivary testosterone levels were strictly within the normal range. Mean serum 17-beta-oestradiol and luteinizing hormone levels (0.19 +/- 0.03 (SEM) nmol/l, and 57.4 +/- 13.1 (SEM) IU/l, respectively) were significantly higher (p less than 0.05 and p less than 0.005, respectively) than in the control group (0.11 +/- 0.02 (SEM) nmol/l and 14.8 +/- 1.9 (SEM) IU/l, respectively). Mean progesterone and follicle-stimulating hormone levels in patients were not significantly different from those of control subjects. Mean prolactin values in patients (1,019 +/- 285 (SEM) mIU/l) were significantly higher (p less than 0.01) than in the control group (211 +/- 24 (SEM) mIU/l). Serum prolactin levels in five patients were extremely high (above 1,200 mIU/l). There was no statistically significant difference in serum zinc levels between patients and controls. As salivary testosterone is normal, it seems that hyperprolactinaemia and raised serum 17-beta-oestradiol levels may be responsible, at least in part, for sexual dysfunction in male patients with chronic renal failure receiving haemodialysis.

Effect of hyperprolactinemia and age on the hypogonadism of uremic men on hemodialysis

Primary hypogonadism has been commonly reported among uremic men on hemodialysis, characterized by low testosterone levels, increased luteinizing hormone and sometimes follicle-stimulating hormone levels. Little is known about the influence of hyperprolactinemia and age on this hypogonadism. In 149 hemodialysis patients and in 60 healthy subjects the serum levels of testosterone (T), gonadotropins (LH and FSH) and prolactin (PRL) were assessed through radioimmunoassay. Mean +/- SD hormone levels were: T 274 +/- 125 ng/100 ml, lower than controls; LH 44.7 +/- 46.1 mlU/ml and FSH 17.6 +/- 18.4 mIU/ml, both higher than controls. PRL 31.3 +/- 49.4 ng/ml, higher than controls. A positive correlation between LH and FSH, a negative correlation between PRL and both T and LH was found. Moreover T and FSH were correlated with age only in the normoprolactinemic patients. These data suggest: a common damaging mechanism by uremia on both interstitial and tubular structures of the testis; a central antigonadal influence of hyperprolactinemia even if a direct action on the testis cannot be excluded; a worsening action of age on the gonadal function of these patients.

Correlation of clinical and in vitro erythropoietic responses to androgens in renal failure

To assess in vitro erythropoietic cultures as a tool to discriminate between patients whose anemia improves with and those whose anemia fails to improve with androgens, bone marrows of 24 anemic patients receiving maintenance hemodialysis in hormone-depleted plasma clots were cultured. While erythroid colony proliferation in the presence and absence of androgens by cells of seven patients with good clinical outcomes who were initially studied was similar to that of normal donors, it was reduced (P less than 0.001) in cultures of cells from seven patients whose clinical responses were ultimately poor. Fewer than 25 colonies/6 X 10(4) cells at optimal erythropoietin concentrations, and less than a 25% enhancement in colony growth by androgens were observed in only those cultures derived from clinical nonresponder marrows. Using these criteria, nine of ten prospectively classified patients (five clinical responders and four nonresponders) were identified correctly.

Diminished response of ovarian cAMP to luteinizing hormone in experimental uremia

In prepuberal female rats with acute bilateral nephrectomy or chronic subtotal nephrectomy, the increase of ovarian cAMP concentration in response to submaximal doses of luteinizing hormone (LH 10 micrograms) and human chorionic gonadotropine (hCG 2.5 IU) was diminished (CO + 2.5 IU hCG 488 +/- 49 pmoles cAMP/mg protein; NX + 2.5 IU hCG 366 +/- 56. P less than 0.05). The cAMP response to follicle stimulating hormone (FSH) was unchanged. The abnormality was found both after administration of LH in vivo and incubation of ovaries with LH in vitro. Similarly, plasma estradiol concentrations in response to submaximal hCG stimulation were diminished. Basal cAMP concentrations and cAMP concentrations after maximal stimulation were unchanged. The defect was observed both in ovaries of untreated prepuberal rats, of pregnant mare serum (PMS)-treated rats (follicular phase) and PMS/hCG-treated rats (luteal phase). Diminished ovarian cAMP response to LH was observed both in parathyroid intact and in parathyroidectomized rats. Administration of 1,25(OH)2D3 in physiological doses (60 ng/kg) to acutely uremic rats restored diminished ovarian cAMP response to submaximal LH stimulation irrespective of parathyroid status. The effect of 1,25(OH)2D3 could not be reproduced by hypercalcemia resulting from intraperitoneal calcium injection. In vivo administration of indomethacin further diminished ovarian cAMP response in uremic animals and had no effect in control animals. Incubation of ovaries with PGE1 and PGE2 increased basal and stimulated cAMP concentrations and abolished the difference between control and uremic animals. The diminished response of ovarian cAMP content to submaximal doses of hCG was not corrected by bromocriptine (1 mg/kg) despite normalization of hyperprolactinemia. The present study shows diminished ovarian cAMP and plasma estradiol response to LH in experimental uremia. It documents a role of 1,25(OH)2D3 and prostaglandins in the genesis of this abnormality.

Zinc, prolactin, gonadotropins, and androgen levels in uremic men

This study correlates plasma levels of Zinc (Zn) and some pituitary and testicular hormones in 20 uremic men (aged 17-58 years) on a weekly peritoneal dialysis program. Patients were compared to 12 healthy male volunteers (aged 28-40 years). In uremic men, plasma androstenedione (A) was elevated, while testosterone (T), dihydrotestosterone (DHT), and Zn were low. On a group basis, plasma follicle stimulating hormone (FSH) and luteinizing hormone (LH) were normal while prolactin was increased. A negative correlation was observed between plasma A and LH levels, as well as between the A/T+DHT ratio and plasma Zn concentrations. Our results suggest a diminished A-to-T conversion and point to the possible role of Zn in the enzyme activity of the 17 beta-hydroxysteroid dehydrogenase.

Reversal of uraemic impotence by zinc

In eight impotent haemodialysed men with low plasma-zinc levels sexual function, including potency, frequency of intercourse, libido, and plasma testosterone, follicle-stimulating hormone, and luteinising hormone levels, was determined before and after therapy with zinc (four patients) or placebo (four patients). Dialytic administration of zinc strikingly improved potency in all patients and raised the plasma-testosterone to normal in the two with low pretreatment plasma-testosterone levels. Placebo did not improve sexual function in any patient. Zinc deficiency is a reversible cause of gonadal dysfunction in uraemia.

Elimination of hormones through hemofiltration

The concentrations of testosterone, cortisone, gastrin, GIP, somatomedin B, insulin, HGH, and TSH have been determined in the plasma and the ultrafiltrate of five uremic patients undergoing intermittent hemofiltration treatment. There was a considerable loss of gastrin, GIP, somatomedin B, and insulin by hemofiltration treatment; the plasma concentrations, however, did not decrease. Cortisone, HGH, and TSH were not detectable in the ultrafiltrate. Our results therefore indicate that hemofiltration does not cause a hormone deficiency syndrome. On the contrary, the loss of degradation products of hormones with disturbing biological activity may be a favourable effect of the hemofiltration treatment.

[Studies on the pituitary-testicular axis in male patients with chronic renal failure with different glomerular filtration rate (author's transl)]

In 32 male patients with chronic renal failure (age 22-60 yrs), of which 17 showed a creatinine clearance below 20 ml/min (group I) and 15 above 20 ml/min (group II), plasma levels of total testosterone (T) and total oestradiol-17beta (E2) were measured before and after stimulation with HCG i.m. LH and FSH were evaluated before and after stimulation with LH-RH i.v. Additionally, testosterone binding capacity (TeBG), free testosterone fraction (%FT) and "absolute" free testosterone (AFT) were determined. In comparison with normal persons T was clearly reduced before and after HCG in group I, whereas in group II it was reduced only after HCG. E2 showed normal basal values in both groups, but in group I it was decreased after HCG. Except for LH values after stimulation in group II, both groups showed increased LH and FSH levels before and after LH-RH in comparison with controls. TeBG and %FT did not show any changes in either group, whereas AFT was reduced in both of them. Comparing the results of group II and I we found in the latter decreased values for T before and after HCG and for E2 after HCG as well as decreased values for AFT, whereas LH and FSH before and after LH-RH were increased. There existed no significant correlation between any of the parameters T, AFT and E2 on the one hand and LH and FSH on the other hand. Significant correlations are found between creatinine clearance and T, AFT, LH and FSH. The results indicate a primary defect of the testis which gradually depends on the degree of renal insufficiency, but with well working feed-back mechanism. The possibility of an additional central regulation defect in the sense of a relative autonomy of the hypophyseal gonadotropin secretion is discussed.

Investigations on pituitary and Leydig cell function in chronic hemodialysis and after renal transplantation

The hypothalamus-pituitary-Leydig cell axis was investigated in 20 male patients undergoing intermittent hemodialysis and in 21 male patients following renal transplantation compared to normal controls. Plasma testosterone as well as luteinizing hormone and follicle stimulating hormone were determined by radioimmunoassay under basal conditions and after stimulation with choriongonadotropic hormone and hypothalamus releasing hormone respectively. Suppressed Leydig cell function has been demonstrated in dialysed patients as well as in patients after renal transplantation. The Leydig cell insufficiency is more pronounced in the hemodialysed patients. None of these showed testosterone levels in the normal range. They are different in various dialysis schedules. In contrast Leydig cell function is much better in patients after renal transplantation compared to those undergoing intermittent hemodialysis. But even after renal transplantation a diminished Leydig cell function takes place. The degree of Leydig cell insufficiency however varies individually. In a few cases Leydig cell function is restored completely after transplantation. It remains uncertain whether the duration of the posttransplantation period or the function of the graft effects Leydig cell function. Anterior lobe insufficiency has been excluded since plasma concentrations of gonadotropins were slightly elevated before and after LH-RH stimulation as compared to normals.

Impotence in patients with chronic renal failure on dialysis: its frequency and etiology

Fourteen patients with chronic renal failure and on a hemodialysis program underwent neurologic, psychiatric, and endocrine studies to determine the frequency and etiology of impotence in uremics. The data suggest that impotence is more frequent in the chronic dialysis group than in the general population. All seven of the impotent men were found to have prolonged nerve conduct on velocity and absent bulbocavernosus reflexes. Several of the impotent men also had clinical depression and low plasma testosterone levels. Neuropathy may be a significant factor in the pathogenesis of impotence in the uremic, but the importance of both psychiatric and endocrine influences must be strongly considered.

Sexual function of males before and after renal transplantation

In an attempt to define changes in sexual function before and after renal transplantation, a questionnaire was distributed to adult male patients with functioning kidney transplants. Significant changes in sexual performance were shown during the transition from the healthy state to end-stage renal failure and, finally, to the post-transplant state. Both potency and libido showed marked parallel impairment with the development of end-stage renal failure, followed by moderate recovery after renal transplantation. This study indicates that the majority of men with functioning kidneys can look forward to a return of sexual activity comparable to pre-illness level. However, sexual impairment may persist in some patients after transplantation, emphasizing the need for further evaluation in this group of patients.