Effect of acute myocardial infarction on pituitary-testicular function

Panhypopituitarism in acute myocardial infarction

While hypopituitarism is known to be associated with increased cardiovascular morbidity and mortality, panhypopituitarism as a complication of myocardial infarction (MI) is very rare. Here, we report a case of rapidly developing empty sella syndrome with florid manifestations of panhypopituitarism after MI (due to critical stenosis in the left anterior descending artery) complicated by cardiogenic shock in a 65-year-old man. The patient was initially stabilized with conservative management of non-ST-elevated MI and cardiogenic shock, but after initial improvement, he again deteriorated with refractory shock (not adequately responding to vasopressors), seizures, hypoglycemia, hyponatremia, hyperkalemia, and metabolic acidosis. After ruling out recurrent cardiogenic shock or other causes of refractory hypotension, panhypopituitarism was diagnosed with the help of hormonal assays and imaging. With no prior evidence of hypopituitarism, we suspect that panhypopituitarism developed due to acute pituitary apoplexy secondary to initial cardiogenic shock. The patient was successfully survived by the emergency endocrine management followed by secondary coronary angioplasty.

Sepsis as a Pan-Endocrine Illness-Endocrine Disorders in Septic Patients

Sepsis is defined as "life-threatening organ dysfunction caused by a dysregulated host response to infection". One of the elements of dysregulated host response is an endocrine system disorder. Changes in its functioning in the course of sepsis affect almost all hormonal axes. In sepsis, a function disturbance of the hypothalamic-pituitary-adrenal axis has been described, in the range of which the most important seems to be hypercortisolemia in the acute phase. Imbalance in the hypothalamic-pituitary-thyroid axis is also described. The most typical manifestation is a triiodothyronine concentration decrease and reverse triiodothyronine concentration increase. In the somatotropic axis, a change in the secretion pattern of growth hormone and peripheral resistance to this hormone has been described. In the hypothalamic-pituitary-gonadal axis, the reduction in testosterone concentration in men and the stress-induced "hypothalamic amenorrhea" in women have been described. Catecholamine and β-adrenergic stimulation disorders have also been reported. Disorders in the endocrine system are part of the "dysregulated host response to infection". They may also affect other components of this dysregulated response, such as metabolism. Hormonal changes occurring in the course of sepsis require further research, not only in order to explore their potential significance in therapy, but also due to their promising prognostic value.

Male hypogonadism: a review

This article contains a systematic review of the main developments that have occurred in the area of male hypogonadism between the publication of the Endocrine Society Guidelines of 2010 and 2018 and after 2018.

Dynamics of testosterone levels in patients with newly detected glucose abnormalities and acute myocardial infarction

OBJECTIVE

Low testosterone has been associated with increased cardiovascular risk and glucose abnormalities. This study explored the prevalence of low testosterone, dynamics over time and prognostic implications in acute myocardial infarction patients with or without glucose abnormalities.

METHODS

Male acute myocardial infarction patients (n = 123) and healthy controls (n = 124) were categorised as having normal or abnormal glucose tolerance (impaired glucose tolerance or diabetes) by oral glucose tolerance testing. Testosterone was measured at hospital admission, discharge, 3 and 12 months thereafter in patients. Patients and controls were followed for 11 years for major cardiovascular events (cardiovascular death/acute myocardial infarction/stroke/severe heart failure).

RESULTS

At hospital admission, more patients had low testosterone (⩽300 ng/dl) and lower median levels than controls (64 vs 28%; p < 0.001 and 243 vs 380 ng/dl; p < 0.01). At the subsequent time points, testosterone had increased to 311, 345 and 357 ng/dl. Patients with abnormal glucose tolerance had the highest prevalence (75%) of low levels. In adjusted Cox regression models, neither total nor free testosterone predicted major cardiovascular events.

CONCLUSION

Low testosterone levels were common in male acute myocardial infarction patients in the acute phase, especially in the presence of abnormal glucose tolerance, but increased over time indicating that testosterone measured in close proximity to acute myocardial infarction should be interpreted with caution.

Proinflammatory Cytokine Infusion Attenuates LH's Feedforward on Testosterone Secretion: Modulation by Age

CONTEXT

In the experimental animal, inflammatory signals quench LH's feedforward drive of testosterone (T) secretion and appear to impair GnRH-LH output. The degree to which such suppressive effects operate in the human is not known.

OBJECTIVE

To test the hypothesis that IL-2 impairs LH's feedforward drive on T and T's feedback inhibition of LH secretion in healthy men.

SETTING

Mayo Center for Translational Science Activities.

PATIENTS OR OTHER PARTICIPANTS

A total of 35 healthy men, 17 young and 18 older.

INTERVENTIONS

Randomized prospective double-blind saline-controlled study of IL-2 infusion in 2 doses with concurrent 10-minute blood sampling for 24 hours.

MAIN OUTCOME MEASURES

Deconvolution analysis of LH and T secretion.

RESULTS

After saline injection, older compared with young men exhibited reduced LH feedforward drive on T secretion (P < .001), and decreased T feedback inhibition of LH secretion (P < .01). After IL-2 injection, LH's feedforward onto T secretion declined markedly especially in young subjects (P < .001). Concomitantly, IL-2 potentiated T's proportional feedback on LH secretion especially in older volunteers.

CONCLUSION

This investigation confirms combined feedforward and feedback deficits in older relative to young men given saline and demonstrates 1) joint mechanisms by which IL-2 enforces biochemical hypogonadism, viz, combined feedforward block and feedback amplification; and 2) unequal absolute inhibition of T and LH secretion by IL-2 in young and older men. These outcomes establish that the male gonadal axis is susceptible to dual-site suppression by a prototypic inflammatory mediator. Thus, we postulate that selected ILs might also enforce male hypogonadism in chronic systemic inflammation.

Low Testosterone Levels are Frequent in Patients with Acute Respiratory Failure and are Associated with Poor Outcomes

OBJECTIVE

Low testosterone level is a common finding in critically ill patients with trauma, shock, and sepsis. However, its prevalence and outcomes in patients with primary acute respiratory failure is unknown; low testosterone could contribute to respiratory muscle weakness and further compromise ventilation in these patients.

METHODS

We aimed to determine the prevalence, severity, and effects of hypotestosteronemia in patients with acute respiratory failure in a 16-bed single academic center medical intensive care unit (ICU). We studied 30 men who required mechanical ventilation for ≥24 hours for a primary diagnosis of acute respiratory failure. Blood samples were drawn on ICU day 1 and day 3 to measure serum levels of total and free testosterone.

RESULTS

Hypotestosteronemia (level below the lower reference limit) was present on day 1 in 93.1% (total testosterone) and 76.7% (free testosterone) of patients and on day 3 in 94.4% (total testosterone) and 100% (free testosterone) of patients. Sex hormone-binding globulin, dehydroepiandrosterone sulfate, follicle-stimulating hormone, luteinizing hormone, and thyroid function levels were all within stated reference ranges. Total and free testosterone levels correlated inversely with ventilator days and ICU length of stay.

CONCLUSION

Hypotestosteronemia is common in mechanically ventilated patients with primary acute respiratory failure and may contribute to longer ICU stay. Further studies are needed to determine the effect of testosterone replacement on short- and long-term outcomes in these patients.

Testosterone levels increase in association with recovery from acute fracture in men

In this longitudinal case-control study, acute fracture was associated with low serum testosterone, which was transient in 43% of men. While assessment of gonadal status is part of the assessment of bone fragility, measurement of testosterone in the early period after fracture may overestimate the prevalence of androgen deficiency.

INTRODUCTION

Measurement of circulating testosterone is recommended in the evaluation of bone fragility in men. Since acute illness can transiently decrease circulating testosterone, we quantified the association of acute fracture and serum testosterone levels.

METHODS

A case-control study was conducted involving 240 men with a radiologically confirmed minimal trauma fracture presenting to a tertiary referral hospital and 89 age-matched men without a history of minimal trauma fracture serving as controls. Follow-up testosterone levels 6 months after baseline were available for 98 cases and 27 controls. Results were expressed as the median and interquartile (IQR) range.

RESULTS

Compared to controls, cases had lower total testosterone [TT, 7.2 (3.5, 10.8) vs 13.6 (10.9, 17.1) nmol/L, p < 0.001]. The 143 cases treated as inpatients had lower testosterone levels than the 97 cases treated as outpatients [TT 4.7 (2.3, 8.1) vs 10.3 (7.5, 12.7) nmol/L, p < 0.001]. Group differences in calculated free testosterone (cFT) were comparable to the group differences in TT. At follow-up, in 98 cases, median TT increased from 6.5 nmol/L (3.2, 8.5) to 9.6 nmol/L (6.9, 12.0) p < 0.0001, and SHBG remained unchanged. Of cases with low testosterone, 43% with TT <10 nmol/L and/or cFT <230 pmol/L at presentation were reclassified as androgen sufficient at follow-up. TT was unchanged in the controls.

CONCLUSIONS

Low testosterone levels in men presenting with an acute fracture may, at least in part, be due to an acute, fracture-associated, stress response. To avoid over diagnosis, evaluation for testosterone deficiency should be deferred until recovery from the acute event.

Hypothalamic-pituitary hormones during critical illness: a dynamic neuroendocrine response

Independent of the underlying condition, critical illness is characterized by a uniform dysregulation of the hypothalamic-pituitary-peripheral axes. In most axes a clear biphasic pattern can be distinguished. The acute phase of critical illness is characterized by low peripheral effector hormone levels such as T3, IGF-1 and testosterone, despite an actively secreting pituitary. The adrenal axis with high cortisol levels in the presence of low ACTH levels is a noteworthy exception. In the prolonged phase of critical illness, low peripheral effector hormone levels coincide with a uniform suppression of the neuroendocrine axes, predominantly of hypothalamic origin. The severity of the alterations in the different neuroendocrine axes is associated with a high risk of morbidity and mortality, but it remains unknown whether the observed changes are cause or consequence of adverse outcome. Several studies have identified therapeutic potential of hypothalamic releasing factors, but clinical outcome remains to be investigated with sufficiently powered randomized controlled trials.

Beneficial and adverse effects of testosterone on the cardiovascular system in men

CONTEXT

The widespread use of T therapy, particularly in aging males, necessitates knowledge of the relationship between T and the cardiovascular system.

EVIDENCE ACQUISITION

The review is based on a 1970 to 2013 PubMed search with terms related to androgens in combination with cardiovascular disease, including T, dihydrotestosterone, trial, mortality, cardiovascular disease, myocardial infarction, blood pressure, endothelial function, dyslipidemia, thrombosis, ventricular function, and arrhythmia. Original articles, systematic reviews and meta-analyses, and relevant citations were screened.

EVIDENCE SYNTHESIS

Low T has been linked to increased blood pressure, dyslipidemia, atherosclerosis, arrhythmia, thrombosis, endothelial dysfunction, as well as to impaired left ventricular function. On the one hand, a modest association is suggested between low endogenous T and incident cardiovascular disease or cardiovascular mortality, implying unrecognized beneficial T effects, residual confounding, or a relationship with health status. On the other hand, treatments with T to restore "normal concentrations" have so far not been proven to be beneficial with respect to cardiovascular disease; neither have they definitely shown specific adverse cardiovascular effects. The cardiovascular risk-benefit profile of T therapy remains largely evasive in view of a lack of well-designed and adequately powered randomized clinical trials.

CONCLUSIONS

The important knowledge gap as to the exact relationship between T and cardiovascular disease would support a cautious, restrained approach to T therapy in aging men, pending clarification of benefits and risks by adequately powered clinical trials of sufficient duration.

Detrimental effects of endogenous oestrogens on primary acute myocardial infarction among postmenopausal women

OBJECTIVE

Traditionally, oestrogens were considered to be protective for the cardiovascular system for premenopausal women. Therefore, we conducted a retrospective case-control study to examine the association between endogenous oestrogens and acute myocardial infarction (AMI) risk among postmenopausal women.

METHODS

A case-control study was performed among 30 primary AMI patients and 60 control subjects. Baseline characteristics data was collected and endogenous sex hormones levels were determined using chemoluminescence and radioimmunoassay methods. Conditional logistic regression models were developed with adjustment for confounders.

RESULTS

Compared with controls, the circulating oestrone, oestradiol, androstenedione and testosterone levels were significantly higher in AMI patients (P < 0.05) while the sex hormone binding globulin (SHBG) level was lower (P < 0.05). Spearman correlation coefficients showed oestradiol was positively correlated with body mass index (BMI) and waist-to-hip ratio (WHR) in cases, but not in controls. In univariable conditional logistic regression models, oestrone, oestradiol, testosterone, WHR, BMI, diabetes and hypertension were all found to be positively associated with AMI (P < 0.05). After adjusting for these factors, oestradiol (odds ratio (OR) = 4.75; 95 % confidence interval (CI) = 1.07-21.10; P = 0.04) and WHR (OR = 6.46; 95 % CI = 1.09-38.39; P = 0.04) continued to demonstrate strong positive associations with AMI.

CONCLUSIONS

A higher level of oestradiol was potentially associated with primary AMI risk among postmenopausal women.

Prevalence of testosterone deficiency after spinal cord injury

OBJECTIVE

To define the prevalence of testosterone deficiency in persons with chronic spinal cord injury (SCI) and to identify factors associated with this deficiency.

DESIGN

Cross-sectional study.

SETTING

A U.S. Department of Veterans Affairs SCI unit.

PARTICIPANTS

Participants (n = 60) included male veterans completing annual evaluations from July 2006 to April 2007.

METHODS

In addition to routine annual evaluation laboratory examination, which included measurements of serum albumin levels, participants underwent measurements of serum total testosterone, luteinizing hormone, follicle stimulating hormone, and prolactin levels. Outcome measures included the prevalence of testosterone deficiency (defined as total serum testosterone <325 ng/dL) and the relationship of testosterone level with participant's age, serum albumin level, narcotic medication use, time since injury, American Spinal Injury Association Impairment Scale (AIS) grade, and neurologic level of injury.

RESULTS

A low serum testosterone level (<325 ng/dL) was detected in 43.3% of participants. The testosterone level was significantly associated with severity of injury as defined by AIS grade (t = -2.59, P = .012). The prevalence of testosterone deficiency was significantly greater in participants with motor complete (AIS A and B) injuries compared with those with motor incomplete (AIS C, D, and E) injuries. Testosterone levels were significantly lower in participants who were taking narcotic medications for pain management (t = -0.25, P < .05). There was no relationship between the use of narcotic medications and severity of injury. Given the small number of participants, the SCI levels, age, duration of injuries, serum albumin levels, and serum levels of luteinizing hormone, follicle stimulating hormone, and prolactin did not reach statistical significance in predicting testosterone level.

CONCLUSIONS

These findings confirm both a substantial population of men with SCI and with testosterone deficiency, and a significant association between testosterone level and severity of SCI. Measuring serum total testosterone levels should be included in standard screenings for patients with SCI, particularly those with motor complete injuries.

Pituitary dysfunction following traumatic brain injury or subarachnoid haemorrhage - in "Endocrine Management in the Intensive Care Unit"

Traumatic brain injury and subarachnoid haemorrhage are important causes of morbidity and mortality in the developed world. There is a large body of evidence that demonstrates that both conditions may adversely affect pituitary function in both the acute and chronic phases of recovery. Diagnosis of hypopituitarism and accurate treatment of pituitary disorders offers the opportunity to improve mortality and outcome in both traumatic brain injury and subarachnoid haemorrhage. In this article, we will review the history and pathophysiology of pituitary function in the acute phase following traumatic brain injury and subarachnoid haemorrhage, and we will discuss in detail three key aspects of pituitary dysfunction which occur in the early course of TBI; acute cortisol deficiency, diabetes insipidus and SIAD.

Nonthyroidal illness syndrome in children

Neuroendocrine changes in the hypothalamic-pituitary-thyroid axis during critical illness result in nonthyroidal illness syndrome (NTIS) characterized by abnormal thyrotropin (TSH) and thyroid hormone levels. Studies looking at the natural history of neuroendocrine changes during critical illness have revealed the presence of NTIS. NTIS has been described in a variety of patient settings. Many studies have tried to uncover the pathophysiology behind NTIS and several theories are proposed. Whether NTIS requires treatment or intervention is still controversial and the results of the treatment studies are arguably mixed. Whether implicitly stated or not, the underlying purpose of all the natural history, pathophysiology, or treatment studies is to determine whether NTIS is adaptive or maladaptive. Some studies have illustrated a correlation between illness severity and the degree of NTIS but a cause and effect relationship is still elusive. The human studies can be divided between those with either adult or pediatric subjects, with much less data available in the latter. This review examines the available literature on NTIS with an emphasis on the pediatric literature.

Characterization of a prospective human model for study of the reproductive hormone responses to major illness

With critical illness, serum testosterone levels fall markedly, whereas estrogen levels rise. Although animal studies suggest adaptive advantages, no prospective model has been available for studies in humans. We hypothesized that coronary artery bypass graft (CABG) surgery would provide such a model by eliciting the same reproductive hormone and other endocrine responses as reported with major nonsurgical illnesses. We further hypothesized that those responses would occur consistently in all CABG patients with predictable time courses, providing reliable windows for prospective studies. In 17 men undergoing CABG, serum levels of reproductive hormones, cortisol, thyroid hormones, and IGF-I were measured before and for up to 5 wk after surgery. Changes in serum levels of reproductive and other hormones were similar to those reported in nonsurgical critically ill patients. Time course for onset, duration, and recovery of reproductive hormone changes were consistent among all patients. A window for studying the testosterone and estrogen responses was established as the first 5 days following CABG. Practical use of this model was demonstrated by evaluating, in another seven men, changes in gonadotroph responsiveness to GnRH following CABG. Finally, to determine whether our findings in CABG could be extended to other surgeries, we demonstrated similar endocrine responses in 12 men following abdominal aortic aneurysm resection. We conclude that patients undergoing CABG surgery provide a useful human model for the prospective evaluation of the reproductive axis responses to acute illness. Other major surgeries are likely to also be suitable for these studies.

Infection, immunity, and hormones/endocrine interactions

Infections and stress, immune responses, and hormones are interconnected, ensuring immune competence to deal with immediate threat of overwhelming infection and metabolic collapse. Emergence of cytokines as key signal mediators and appreciation of autocrine-paracrine influences of hormones have helped explain how signals are transmitted and responses evoked. This has led to possibilities of creating therapies that might be used to enhance protective signals and dampen signals emanating from host and invading organism interaction that might otherwise be detrimental. Correcting certain metabolic abnormalities, such as hyperglycemia and metabolic acidosis, benefits the host by decreasing morbidity and mortality.

Male hypogonadism in systemic disease

Hypogonadism is often observed in the presence of common acute and chronic illnesses in men. Low testosterone levels in these patients can be associated with loss of lean body mass and bone mass density, decline in mood, loss of energy, and sexual dysfunction. The mechanisms explaining hypogonadism and various systemic diseases are not completely understood, but these conditions are likely caused by a combination of stress, nonspecific weight loss, inflammation, and medication. Testosterone replacement can be considered in this population to improve lean body mass, bone mass density, and quality of life. More information is needed regarding the risk benefits of testosterone treatment on health outcomes in men who have systemic illness.

Quantification of testosterone and epitestosterone in human urine samples by stir bar sorptive extraction – thermal desorption – gas chromatography/mass spectrometry: Application to HIV-positive urine samples

A simple method is described for the measurement of testosterone (T) and epitestosterone (ET) in human urine samples. The deconjugated steroids were extracted directly from the samples by stir bar sorptive extraction (SBSE) and derivatized in situ on the stir bar by headspace acylation prior to thermal desorption and GC/MS. Extraction and derivatization parameters, namely salt addition, temperature, and time, were optimized to improve the recovery of T and ET by SBSE. The limits of quantification (S/N 10) were 0.9 ng/mL for T and 2.8 ng/mL for ET. Quantification of the steroids in urine samples was performed using standard addition to avoid the influence of matrix effects. The method was applied for the measurement of urinary T and ET in a group of healthy volunteers and HIV+ patients. Decreased levels of T were detected in the HIV+ group, whereas the excretion of ET was comparable for the two groups. Further clinical research is required to elucidate the biomarker significance of the T/ET ratio in HIV infection.

The inflammatory response to surgery and trauma

PURPOSE OF REVIEW

The inflammatory or stress response to injury has evolved to ensure survival. This review will examine this response in otherwise healthy patients. Additionally, the impact of several common comorbid conditions on the inflammatory response will be considered. What will become evident is that the stress response may be exaggerated in some conditions and suppressed in others. Rapid identification of both an abnormal response and its cause will allow clinicians to maximize a patient's healing potential.

RECENT FINDINGS

Recent work has shown that an altered inflammatory response has marked effects on both immune competence and the endocrine system. Investigations are ongoing to delineate the mechanism of lymphocyte dysfunction. With regard to critical care endocrinopathies, the effects of insulin and hyperglycemia on inflammation and wound healing are being investigated.

SUMMARY

An understanding of the stress response will aid the clinician in preparing for expected responses, recognizing and perhaps correcting deviations from the norm and accounting for potential complications that arise in the face of preexisting disease. Deviations from the normal time course may represent the effects of preexisting medical illness, treatment or postoperative/injury complications.

The dynamic neuroendocrine response to critical illness

The severity of striking alterations in the hypothalamic-anterior pituitary-peripheral hormone axes, which are the hallmark of severity of critical illness, is associated with a high risk for morbidity and mortality. Most attempts to correct the hormone balance are ineffective or harmful because of lack of pathophysiologic understanding. Extensive research has provided more insight in the biphasic neuroendocrine response to critical illness: the acute phase is characterized by an actively secreting pituitary but low peripheral effector hormone levels. In contrast, in prolonged critical illness, uniform suppression of the neuroendocrine axes, predominantly of hypothalamic origin, contributes to low serum levels of the respective target-organ hormones.

Endocrine aspects of acute and prolonged critical illness

Critical illness is characterized by striking alterations in the hypothalamic-anterior-pituitary-peripheral-hormone axes, the severity of which is associated with a high risk of morbidity and mortality. Most attempts to correct hormone balance have been shown ineffective or even harmful because of a lack of pathophysiologic insight. There is a biphasic (neuro)endocrine response to critical illness. The acute phase is characterized by an actively secreting pituitary, but the concentrations of most peripheral effector hormones are low, partly due to the development of target-organ resistance. In contrast, in prolonged critical illness, uniform (predominantly hypothalamic) suppression of the (neuro)endocrine axes contributes to the low serum levels of the respective target-organ hormones. The adaptations in the acute phase are considered to be beneficial for short-term survival. In the chronic phase, however, the observed (neuro)endocrine alterations appear to contribute to the general wasting syndrome. With the exception of intensive insulin therapy, and perhaps hydrocortisone administration for a subgroup of patients, no hormonal intervention has proven to beneficially affect outcome. The combined administration of hypothalamic releasing factors does, however, hold promise as a safe therapy to reverse the (neuro)endocrine and metabolic abnormalities of prolonged critical illness by concomitant reactivation of the different anterior-pituitary axes.

Increases in serum estrogen levels during major illness are caused by increased peripheral aromatization

Although serum testosterone levels decrease acutely in critically ill patients, estrogen levels rise. We hypothesized that increased rates of aromatization of androgens to estrogens underlie the increase in serum estrogen levels. Eleven men and three women (age 42-69 yr) were prospectively studied before and again after elective coronary artery bypass graft surgery (CABG). Each patient received priming doses of [(14)C]androgen and [(3)H]estrogen that were immediately followed by peripheral infusions for 210 min. Eight men and three women received androstenedione (A(4))/estrone (E(1)) and three men received testosterone (T)/estradiol (E(2)). Adipose tissue biopsies were obtained in another six men before and after CABG to evaluate levels of P450 aromatase mRNA. Serum T levels decreased postoperatively in all 17 men (P < 0.001), whereas E(1) levels rose (P = 0.004), with a trend toward a rise in E(2) (P = 0.23). Peripheral aromatization rates of androgens to estrogens rose markedly in all 14 patients (P < 0.0001). Estrogen clearance rates rose (P < 0.002). Mean serum A(4) levels increased slightly postoperatively (P = 0.04), although no increase in A(4) production rates (PRs) was observed. T PRs decreased in two of three men, whereas clearance rates increased in all three. Adipose tissue P450 aromatase mRNA content increased postoperatively (P < 0.001). We conclude that the primary cause of increased estrogen levels in acute illness is increased aromatase P450 gene expression, resulting in enhanced aromatization of androgens to estrogens, a previously undescribed endocrine response to acute illness. Both increased T clearance and decreased T production contribute to decreased serum T levels. Animal studies suggest that these opposing changes in circulating estrogen and androgen levels may be important to reduce morbidity and mortality in critical illness.

The Neuroendocrine Response to Critical Illness is a Dynamic Process

Striking alterations in the hypothalamic-anterior pituitary-peripheral hormone axes hallmark the state of critical illness, their severity being associated with high risk for morbidity and mortality. Early endocrine intervention strategies aimed to correct the hormone balance have been shown ineffective or even harmful because of lack of thorough pathophysiologic understanding of these neuroendocrine changes. Extensive research, however, has provided crucial insights, with the demonstration of the biphasic response of the anterior pituitary to the severe stress of critical illness.

The Endocrine Response to Critical Illness: Update and Implications for Emergency Medicine

This review will provide an updated overview of the neuroendocrine response to critical illness. Specifically, the current evidence for "stress steroid" administration will be examined, as well as interventional glucose control during critical illness. The emergency physician will also find relevance in the alterations of thyroid hormones that occur in the face of severe illness or trauma.

Endocrine evaluation of patients with critical illness

Prolonged critical illness has a high morbidity and mortality. The acute and chronic phases of critical illness are associated with distinct endocrine alterations. The acute neuroendocrine response to critical illness involves an activated anterior pituitary function. In prolonged critical illness, however, a reduced pulsatile secretion of anterior pituitary hormones and the so-called "wasting syndrome" occur. The impaired pulsatile secretion of GH, thyrotropin and gonadotropin can be re-amplified by relevant combinations of releasing factors, which also substantially increase circulating levels of IGF-1, GH-dependent IGFBPs, thyroxin, tri-iodothyronine and testosterone. Anabolism is clearly re-initiated at the time GH secretagogues, thyrotropin-releasing hormone and gonadotropin-releasing hormone are coadministered but the effect on survival remains unknown. A lethal outcome of critical illness is predicted by a high serum concentration of IGFBP-1, pointing to impaired insulin effect rather than pituitary function, and survival was recently shown to be dramatically improved by strict normalization of glycemia with exogenous insulin. In addition to the illness-induced endocrine alterations, patients may have pre-existing central or peripheral endocrine diseases, either previously diagnosed or unknown. Hence, endocrine function testing in a critically ill patient represents a major challenge and the issue of treatment remains controversial. The recent progress in knowledge of the neuroendocrine response to critical illness and its interrelation with peripheral hormonal and metabolic alterations during stress, allows for potential new therapeutic perspectives to safely reverse the wasting syndrome and improve survival.

Dynamic neuroendocrine responses to critical illness

Prolonged critical illness has high morbidity and mortality. The acute neuroendocrine response to critical illness involves an activated anterior pituitary function. In prolonged critical illness, however, a reduced pulsatile secretion of anterior pituitary hormones and the so-called 'wasting syndrome' occur. The impaired pulsatile secretion of growth hormone (GH), thyrotropin and gonadotropin can be re-amplified by relevant combinations of releasing factors, which also substantially increase circulating levels of insulin-like growth factor (IGF)-I, GH-dependent IGF-binding proteins, thyroxine, tri-iodothyronine, and testosterone. Anabolism is clearly re-initiated when GH secretagogues, thyrotropin-releasing and gonadotropin-releasing hormones are co-administered but the effect on survival remains unknown. A lethal outcome of critical illness is predicted by a high serum concentration of IGF-binding protein 1, pointing to impaired insulin effect rather than pituitary function, and survival was recently shown to be dramatically improved by strict normalization of glycemia with exogenous insulin. The recent progress in the knowledge of the neuroendocrine response to critical illness and its interrelation with peripheral hormonal and metabolic alterations during stress allows for potential new therapeutic perspectives to safely reverse the wasting syndrome and improve survival. These novel insights will be reviewed herein.

Bio-available testosterone levels fall acutely following myocardial infarction in men: association with fibrinolytic factors

The effect of acute myocardial infarction on plasma levels of testosterone in men is unclear. No previous studies have evaluated the bio-available fraction of testosterone. Low plasma testosterone levels have been associated with several risk factors for myocardial infarction, including an unfavorable fibrinolytic profile. In a prospective, case control study, we examined changes in plasma levels of sex hormones, including bio-available testosterone, in patients with acute myocardial infarction and in control subjects. In addition, changes in hormone levels in patients were compared with alterations in the fibrinolytic profile. Thirty male patients admitted with chest pain were studied. Twenty two had acute myocardial infarction and eight had non-specific chest pain. Plasma levels of total and bio-available testosterone, 17beta-estradiol, sex hormone binding globulin and insulin were measured at baseline and throughout admission. In addition, fibrinolytic factors (plasminogen activator inhibitor-1 (PAI-1), tissue plasminogen activator (tPA) and fibrinogen) were measured in patients who received fibrinolysis. Height and weight, and the subsequent development of heart failure or myocardial dysfunction were also recorded. Patients had lower levels of bio-available testosterone (2.07 +/- 0.75 nmol/L vs. 5.3 +/- 1.7 nmol/L, p < 0.05) and higher levels of 17beta-estradiol (87.9 +/- 39.5 pmol/L vs. 48.1 +/- 18.4 pmol/L, p < 0.001) than controls. Total and bio-available testosterone levels fell acutely following myocardial infarction (11.9 +/- 3.8 nmol/L to 9.7 +/- 3.3 nmol/L, p < 0.05; 1.95 +/- 0.76 nmol/L to 1.55 +/- 0.67 nmol/L, p < 0.05). This reduction was associated with elevation of PAI-I activity and reduction of tPA activity, independent of changes in plasma insulin levels. Patients with lower baseline levels of testosterone and higher levels of 17beta-estradiol had a relatively pro-thrombotic fibrinolytic profile and increased risk of complications. In conclusion, total and bio-available levels of testosterone fall following acute myocardial infarction in men, in association with adverse changes in fibrinolytic profile. It is not clear whether this association represents a direct effect of testosterone on thrombotic tendency but warrants further investigation.

Endocrine and metabolic issues in the management of the chronically critically ill patient

The metabolic syndrome of chronic critical illness (CCI) consists of multisystem organ dysfunction resulting from the initial acute injury and chronic immune-neuroendocrine axis activation, adult kwashiorkor-like malnutrition, and prolonged immobilization with suppression of the PTH-vitamin D axis and hyper-resorptive metabolic bone disease. CCI patients can also present unique challenges in the management of diabetes mellitus, thyroid and adrenal diseases, electrolyte abnormalities and hypogonadism.

Neuroendocrine pathobiology of chronic critical illness

The neuroendocrine stress response is a dynamic process involving multiple hormonal alterations with distinct features in the acute and chronic phase of critical illness. In the initial response to an acute stress event, the anterior pituitary actively releases its hormones into the circulation while in the periphery, anabolic target organ hormones are inactivated. This response is thought to be beneficial and adaptive. When critical illness becomes prolonged, pulsatile secretion of anterior pituitary hormones becomes uniformly reduced due to reduced (hypothalamic) stimulation, and this underlies reduced activity of the respective target tissues and impaired anabolism. This difference in the acute and chronic stress response may not be trivial. It was the (inappropriate) assumption that acute stress responses, such as GH resistance, persist throughout the course of critical illness, which had formed the (inappropriate) justification to administer high doses of GH to long-stay intensive care patients to induce anabolism [102]. The concomitant endocrine changes in chronic critical illness may have predisposed to severe side effects of high doses of GH. In view of the significant benefits of strict glycemic control using exogenous insulin recently demonstrated in ICU patients [101], GH-induced insulin resistance and hyperglycemia may have played a role. It remains to be studied whether endocrine intervention with releasing factors such as TRH and GHRP in prolonged critical illness will accelerate recovery of patients who have entered the vicious circle of prolonged intensive care dependency.

Altered gonadal steroidogenesis in critical illness: is treatment with anabolic steroids indicated?

The physiology of the reproductive system changes dramatically with the onset of major illness. The serum testosterone concentrations fall to pre-pubertal levels secondary to a decreased secretion of gonadotropins and a decreased Leydig cell response to luteinizing hormone. At the same time, the serum oestrogen concentration rises as the result of an increased rate of peripheral aromatization. The clinical consequences of these marked changes are not yet well understood. One line of evidence argues for the administration of anabolic steroids (derivatives of testosterone) to critically ill patients to improve their catabolic state. Another line of evidence in animal models suggests that testosterone may suppress the immune system and myocardial function in critical illness. No clinical trials of oestrogen administration to critically ill patients have been reported, although two animal studies suggest that oestrogen may have a positive effect on survival. This chapter reviews changes in the physiology of the reproductive system in major illness as well as current evidence regarding the clinical effects of androgens and oestrogens in critical illness and their potential therapeutic roles.

The neuroendocrine response to stress is a dynamic process

The initial neuroendocrine response to critical illness illness consists primarily of activated anterior pituitary function, the peripheral anabolic pathways being inactivated. This response presumably provides metabolic substrates, establishes the host's defences and is thus considered to be adaptive and beneficial. It was previously assumed that the acute stress response persisted throughout the course of critical illness, but this assumption has now been disproved. Indeed, a uniformly reduced pulsatile secretion of growth hormone, thyroid-stimulating hormone, prolactin and luteinizing hormone has been observed in protracted critical illness, impairing the function of target organs. A reduced availability of thyrotropin-releasing hormone, gonadotropin-releasing hormone, the endogenous ligand of the growth hormone-releasing peptide receptor (possibly ghrelin) and, in very long-stay critically ill men, also growth hormone-releasing hormone seems to be involved. The pulsatile secretion of growth hormone, thyroid-stimulating hormone, prolactin and luteinizing hormone can be re-established by relevant combinations of releasing factors, which also substantially increase the circulating levels of insulin-like growth factor-1, growth hormone dependent binding proteins, thyroxine, tri-iodothyronine and testosterone. Active feedback inhibition loops prevent the target organs being overstimulated. The metabolism is altered in a beneficial way when growth hormone-secretagogues, thyrotropin-releasing hormone and gonadotropin-releasing hormone are administered together, whereas the effect of single-hormone treatment is minor and accompanied by side-effects. This new concept of a selectively reduced stimulation of pituitary function in the chronic phase of critical illness unveils new therapeutic perspectives to reverse the paradoxical wasting syndrome' and intensive care dependency.

Andropausa: insuficiência androgênica parcial do homem idoso. Uma revisão

Andropausa é uma designação inapropriada para o quadro clínico resultante do declínio progressivo da produção androgênica encontrado em pelo menos 20% dos homens com idade entre 60 e 70 anos, e que algumas vezes se inicia a partir dos 50 anos. Uma designação mais adequada é insuficiência androgênica parcial do homem idoso. Como a produção de testosterona diminui regularmente, em homens de 75 anos os níveis médios de testosterona são somente 65% daqueles dos adultos jovens, sendo que pelo menos 25% destes idosos apresentam níveis subnormais de testosterona biodisponível. A etiologia deste declínio da testosterona dependente da idade é multifatorial e envolve alterações testiculares primárias, disfunção da regulação neuroendócrina das gonadotropinas, elevação das concentrações séricas de globulina ligadora de hormônios sexuais e redução da sensibilidade dos receptores androgênicos. A senescência é acompanhada de uma série de sinais e sintomas, muitos deles bastante semelhantes aos observados em hipogonádicos jovens. Este quadro clínico complexo pode se dever aos efeitos conjuntos do próprio processo de senescência e de doenças intercorrentes. No entanto, existem evidências que o declínio dos níveis de testosterona próprio da idade é, pelo menos em parte, codeterminante deste quadro clínico, visto que a reposição androgênica tem mostrado efeitos favoráveis em mais de 30% destes idosos sintomáticos. No momento, esta reposição hormonal deveria somente ser considerada em presença de níveis séricos de testosterona abaixo dos limites normais mínimos para adultos jovens, acompanhada de sinais inequívocos de insuficiência androgênica, na ausência de outras causas reversíveis de hipoandrogenismo e após a exclusão de contra-indicações.

Hypotestosteronemia in chronically critically ill men

OBJECTIVE

To determine the prevalence of hypotestosteronemia in chronically critically ill (CCI) men.

DESIGN

Prevalence survey.

SETTING

Step-down respiratory care unit (RCU) at a tertiary care teaching hospital.

PATIENTS

Thirty ventilator-dependent CCI men transferred from intensive care units (ICUs) within the same institution.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Total testosterone and bioavailable testosterone (bioT) concentrations were measured within 48 hrs of RCU admission. Patients were hospitalized a median of 40 days (range, 9-185 days) before RCU admission, with a median ICU length of stay of 25 days (range, 9-177 days). At RCU admission, total testosterone concentrations averaged 104+/-96 ng/dL, with average bioT concentrations of 19+/-20 ng/dL (16+/-9% of total testosterone). Twenty-nine of the 30 patients (96%) had bioT concentrations well below the lower limit of normal for their age range. bioT concentrations, expressed as a percentage of the normal mean for each patient's age range, were positively correlated with the number of days that the patient was in the ICU before transfer to the RCU (n = 30, r2 = .17, p = .025). However, if the single patient who remained in the ICU for 177 days was excluded, this correlation disappeared (n = 29, r2 = .07, p = .09). No other relationship was found between bioT concentrations and any other variable, including type of patient, ICU length of stay, reason for either initial admission to the ICU or prolonged mechanical ventilation, type of nutritional support, or use of dopamine.

CONCLUSIONS

CCI men have a very high prevalence of hypotestosteronemia, which may impede their recuperation and rehabilitation. Further studies are needed to determine whether additional pharmacologic treatment with testosterone can improve the recovery of these patients.

Declining gonadal function in elderly men

Ageing in men is accompanied by a progressive decline of gonadal function with, in particular, a decline of total and free testosterone (T) plasma levels resulting in a significant proportion of elderly men over age 60 years presenting with subnormal T levels compared with the levels in young adults. A great interindividual variation in T levels is observed in elderly men, a variability explained in part by physiological variables and differences in life style, while associated acute or chronic diseases may accentuate the age-related decline of T levels. The progressive decrease of plasma T levels has been shown to result from both primary testicular changes and altered neuroendocrine regulation of Leydig cell function. At present, little is known about the clinical relevance of the relative hypoandrogenism of elderly men and there is an urgent need for more longitudinal studies, which may clarify a possible role of decreased T levels in the modulation of the clinical consequences of ageing in men. In view of the lack of relevant controlled clinical trials having careful assessment of the risks and benefits of androgen replacement therapy in elderly men, this treatment should be reserved for selected patients with clinically and biochemically manifest hypogonadism, after careful screening for contraindications.

Decreased serum testosterone in men with acute ischemic stroke

Serum levels of total and free testosterone and 17 beta-estradiol were determined in 144 men with acute ischemic stroke and 47 healthy male control subjects. Blood samples from patients were drawn a mean of 3 days after stroke onset and also 6 months after admission in a subgroup of 45 patients. Initial stroke severity was assessed on the Scandinavian Stroke Scale and infarct size by computed tomographic scan. Mean total serum testosterone was 13.8 +/- 0.5 nmol/L in stroke patients and 16.5 +/- 0.7 nmol/L in control subjects (P = .002); the respective values for free serum testosterone were 40.8 +/- 1.3 and 51.0 +/- 2.2 pmol/L (P = .0001). Both total and free testosterone were significantly inversely associated with stroke severity and 6-month mortality, and total testosterone was significantly inversely associated with infarct size. The differences in total and free testosterone levels between patients and control subjects could not be explained by 10 putative risk factors for stroke, including age, blood pressure, diabetes, ischemic heart disease, smoking, and atrial fibrillation. Total and free testosterone levels tended to normalize 6 months after the stroke. There was no difference between patients and control subjects in serum 17 beta-estradiol levels. These results support the idea that testosterone affects the pathogenesis of ischemic stroke in men.

Male pituitary-gonadal dysfunction following severe traumatic brain injury

A prospective study was conducted to evaluate pituitary-gonadal function and correlated parameters in 21 adult males with severe traumatic brain injury during acute inpatient rehabilitation. Serum concentrations of testosterone, follicle-stimulating hormone (FSH) and luteinizing hormone (LH) were measured within 1 week after the patient was transferred to the rehabilitation unit. Fourteen of 21 patients (67%) had abnormally low testosterone levels. One of 21 patients had a subnormal FSH level and one had a supranormal level. Three of 21 patients had subnormal LH levels and two had supranormal levels. There was no correlation between the severity of brain injury and the levels of testosterone, FSH or LH. The presence of increased intracranial pressure, hypoxia, skull fracture or abnormal CT findings had no significant influence on the levels of testosterone, FSH or LH. The high incidence of hypotestosteronaemia in survivors of severe traumatic brain injury is seemingly more related to accompanying physiological stressors rather than structural or neurochemical disruption of the hypothalamic-pituitary-gonadal axis. Early identification is important relative to the potential neuromedical and rehabilitative consequences of prolonged hypotestosteronaemia in this patient population.

Pituitary-gonadal dysfunction in male patients with lung cancer. Association with serum inhibin levels

Male lung cancer patients with poor performance status have an endocrinological dysfunction shown by decreased serum levels of total and free testosterone (AFTC). The intention was to investigate whether or not inhibin plays a role in gonadal dysfunction observed in male patients with malignant pulmonary disease. Twenty-seven patients with locally advanced non-small cell lung cancer were included. Sixteen patients were within ECOG index 1-2 (group A) and 11 patients within ECOG index 3-4 (group B). Gonadal function was monitored by serum LH, FSH, testosterone, SHBG and inhibin levels. Patients with poor performance status displayed significantly lower inhibin (1.6 +/- 0.8 U/I) and AFTC (0.23 +/- 0.07 nmol/l) levels when compared to patients within ECOG index 1-2 (inhibin 2.4 +/- 1.1 U/I; AFTC 0.66 +/- 0.36 nmol/l). Serum inhibin tended to correlate inversely to FSH with a 4.4-fold higher FSH/inhibin ratio in group B compared to A.

Reversal of sexual impotence in male patients with chronic obstructive pulmonary disease and hypoxemia with long-term oxygen therapy

Erectile impotence is commonly encountered in male patients with respiratory failure and hypoxia. In this study, 42% of the patients experienced reversal of sexual impotence during long-term oxygen therapy (LTOT). We examine the association between sexual impotence, gonadal axis hormones, hypoxia, and oxygen therapy. Nineteen sexually impotent male patients eligible for LTOT (pO2 < 7.3 kPa during stable disease) and with sexual impotence received oxygen therapy for 1 month (n = 12) or 24 h (n = 7). pO2, LH, FSH, testosterone, and SHBG (sex hormone binding globulin) were monitored. Five of 12 patients receiving oxygen for 1 month regained sexual potency. The responders showed a significant increase in arterial pO2 and serum testosterone, and a decline in SHBG compared to non-responders. None of the patients receiving oxygen for 24 h experienced reversal of sexual impotence, despite a significant increase in pO2. In these patients, serum testosterone did not increase significantly. Reversal of sexual impotence may be achieved in some patients with respiratory failure. The oxygen therapy must, however be administered for an adequate length of time.

Testosterone deficiency as a risk factor for hip fractures in men: a case-control study

The objective of this study was to determine whether decreased gonadal function is a risk factor for hip fracture in elderly men. The study was a matched case-control study performed at an in-hospital orthopedic service at a semi-rural and academic tertiary care center. The patients were seventeen men who presented with hip fractures after simple falls over a 10-month period, 11 men with a history of hip fractures in the preceding 25 months, and 28 randomly selected age-, race-, and living status-matched control subjects (mean age 73 years). Serum pooled total testosterone (9.2 +/- 5.5 nmol/L vs. 12.8 +/- 5.4 nmol/L; p less than 0.02) and free testosterone (37.9 +/- 18.8 pmol/L vs. 48.4 +/- 20.6 pmol/L; p less than 0.03) were significantly lower in hip fracture vs. control patients. Testosterone deficiency was found in 20 (71%) hip fracture men vs. 9 (32%) of the controls (p = 0.003; odds ratio 5.3). Analysis of testosterone values within the stratum of absence of any chronic disorder revealed similar results. Serum 25-hydroxyvitamin D levels were significantly lower in the hip fracture group than in control men (p less than 0.001). The conclusion is that gonadal deficiency appears to be an important and heretofore understudied risk factor for hip fractures in men. Prevention of hip fractures in men may involve early recognition and treatment of testosterone deficiency.

Abnormalities of the hypothalamo-pituitary-gonadal axis after head injury

OBJECTIVE

We aimed to investigate the mechanisms of hypogonadism which develops after head injury.

DESIGN

Pulsatile secretion of LH was studied in subjects 6-10 days after major head injury.

PATIENTS

We studied five male subjects admitted with major head injuries and six healthy age-matched control subjects.

MEASUREMENTS

During the pulsatility study, LH was measured at 5-minute intervals for 4 hours and 15-minute intervals for a further 2 hours. In addition, testosterone and LH were measured on Days 1-5, 14 and after 3-6 months.

RESULTS

The analysis of pulsatile secretion of LH demonstrated an LH pulse frequency similar to control subjects, but a significantly reduced LH pulse amplitude (P less than 0.001, fixed threshold method; P less than 0.02, Detect method). Both testosterone and LH levels were reduced after injury with the nadir occurring on Day 4.

CONCLUSIONS

Hypogonadism after head injury is due to defective LH secretion, with normal pulse frequency but a reduced pulse amplitude.

Circulating immunoreactive inhibin and testosterone levels in men with critical illness

OBJECTIVE

We aimed to concurrently characterize serial changes in circulating immunoreactive inhibin (irINH) and testosterone (T) as reflections of Sertoli and Leydig cell responses to acute critical illness in man.

DESIGN

Blood samples were drawn within 24 hours of admission to an Intensive Care Unit and at weekly intervals thereafter for up to 4 weeks while the patient remained in Intensive Care Unit or after discharge to a general ward.

PATIENTS

We studied 13 male subjects with critical illness requiring intensive therapy.

MEASUREMENTS

Plasma levels of irINH, T, LH, FSH and sex hormone binding globulin (SHBG) were analysed in relation to (i) the severity of illness as indicated by a sepsis score, acute physiology and chronic health evaluation score, and reverse triiodothyronine (rT3) levels and (ii) the outcome of illness as determined by discharge from Intensive Care Unit and the two-month mortality.

RESULTS

Overall irINH levels remained normal and correlated negatively with rT3 (r = -0.63, P = 0.001) but not with sepsis, acute physiology and chronic health evaluation score, or gonadotrophin levels. Neither admission nor serial irINH levels significantly distinguished between the different clinical outcomes. In contrast, T levels were depressed and inversely correlated with both sepsis and acute physiology and chronic health evaluation scores (P less than 0.02), and positively with gonadotrophins (P less than 0.01), but not rT3 levels. Men eventually discharged from the Intensive Care Unit showed a rise, while those remaining showed a fall, in T levels (P = 0.02, time-course interaction). Similarly, T levels were lower in patients who died than in survivors, despite the comparable T levels on admission (P = 0.02, time-course interaction). Despite the fall in T levels, gonadotrophin levels remained inappropriately in the eugonadal range but higher in men who were discharged from Intensive Care Unit (P = 0.02, time-course interaction). FSH but not LH levels were correlated with sepsis score (P = 0.02) but not acute physiology and chronic health evaluation score or rT3.

CONCLUSIONS

Sertoli cell function as judged by circulating irINH levels is much less affected by acute critical illness than is Leydig cell function as judged by circulating T levels. The suppressive effect of acute critical illness on Leydig cell function is consistent with a hypothalamic-pituitary lesion.

Subnormal serum testosterone levels in male internal medicine residents

The consequences of sleep deprivation and stress in residency training have not been quantified. In the course of assembling a control group for other studies, we unexpectedly observed a significant (P less than 0.005) and marked depression of serum testosterone levels in healthy male internal medicine residents (means = 11.8 +/- 1.1 nmol/L, n = 7) compared with other hospital personnel (means = 20.6 +/- 5.3 nmol/L, n = 18). Testosterone concentrations in the two groups were entirely nonoverlapping, while luteinizing hormone levels were not significantly different. We conclude that the stress of residency training leads to a quantifiable depression of gonadal function, and that gonadal steroid concentrations may be useful in evaluating measures intended to reduce that stress.

Endogenous sex hormones and cardiovascular disease in men. A prospective population-based study

Plasma obtained and frozen in 1972-1974 from 1,009 white men (40-79 years old) who have been followed for 12 years was examined for endogenous sex hormone levels according to prevalent or subsequent cardiovascular disease. In these older men, no sex hormone measured (testosterone, androstenedione, estrone, or estradiol) was significantly associated with known cardiovascular disease at baseline or with subsequent cardiovascular mortality or ischemic heart disease morbidity or mortality. Sex hormone-binding globulin levels were also similar by disease status. Analyses of hormone:sex hormone-binding globulin ratios or of estrogen:androgen ratios showed a similar lack of association with cardiovascular disease. Testosterone levels were significantly inversely associated with levels of blood pressure, fasting plasma glucose, and triglyceride and body mass index. In contrast, the only significant estrogen risk factor associations were positive correlations of estrone with total plasma cholesterol, triglyceride, and glucose. These data do not support a causal role for elevated endogenous estrogen levels and heart disease.

Endocrine disorders in men infected with human immunodeficiency virus

Gonadal, adrenal, and thyroid functions were evaluated in 70 men seropositive for human immunodeficiency virus (HIV) infection, clinically categorized as asymptomatic (n = 19), AIDS-related complex (ARC) (n = 9), or acquired immunodeficiency syndrome (AIDS) (n = 42). Twenty of 40 men (50 percent) with AIDS were hypogonadal. Mean serum testosterone concentrations in both ARC (292 +/- 70 ng/dl) and AIDS (401 +/- 30 ng/dl) men were significantly less than in asymptomatic (567 +/- 49 ng/dl) or normal men (608 +/- 121 ng/dl). Of these hypogonadal men, 18 of 24 (75 percent) had hypogonadotropic hypogonadism. Seven of eight hypogonadal men (88 percent) had a normal gonadotropin response to gonadotropin-releasing hormone administration. Hypogonadism correlated with lymphocyte depletion and weight loss. Adrenal cortisol reserve, evaluated by adrenocorticotropin stimulation, was normal in 36 of 39 patients (92 percent) with AIDS. Indices of thyroid function were normal with the exception of one ARC man with a low free thyroxine index. In conclusion, hypogonadism is common in men with HIV infection and may be the first or most sensitive endocrine abnormality.

Usefulness of sex steroid hormone levels in predicting coronary artery disease in men

The relation between sex hormone levels and subsequent risk of a major coronary event was studied in a nested case-control study among 163 men in the Multiple Risk Factor Intervention Trial who later had a major coronary event and in 163 controls. Cases and controls were matched for age, serum cholesterol level, randomization group, randomization date and clinic. Blood samples were collected at baseline before randomization and frozen at -70 degrees C. Follow-up extended over 6 to 8 years. Sixty-one patients had a nonfatal acute myocardial infarction and 102 fatal infarction. Total and free testosterone, total and free estradiol, androstenedione and estrone concentrations were measured. There were no significant differences between cases and controls for any sex hormone level. There was also no difference in the ratio of testosterone to estradiol. Controlling for other cardiovascular risk factors did not change these results. These results do not support previous case-control studies of a relation between sex hormone levels and risk of heart attack among men.

Mechanisms leading to hypogonadism in men with burns injuries

A profound and persistent depression of serum testosterone concentrations was found in 19 men with burns injuries. This could not be explained by changes in sex hormone binding globulin capacity, hyperprolactinaemia, classical primary testicular failure, or a hypogonadotrophic state. Pulsatile release of luteinising hormone was found in control subjects but was absent or diminished in burnt patients with low serum testosterone concentrations. In addition, these patients showed reduced biological activity of luteinising hormone as measured by bioassay even though normal concentrations of luteinising hormone were detected by radioimmunoassay. The temporary hypogonadism after burns injury and possibly in other clinical states may be related to hypothalamic dysfunction, which leads to abnormal generation of luteinising hormone releasing hormone and non-pulsatile secretion of luteinising hormone of reduced biological activity.

Chorionic villi sampling: cytogenetic and clinical findings in 500 pregnancies

The cytogenetic findings were analysed in a series of 500 pregnancies in which chorionic villi sampling was performed. In all cases a direct method was used, karyotyping being successful in 481 cases (96.2%). The main indication for sampling was maternal age over 36 (412 cases; 82.4%). Abnormal laboratory findings resulted in 24 terminations of pregnancy (4.8%); in addition five unexpected balanced chromosome rearrangements were detected. Twelve of 15 cytogenetic discrepancies were detected at amniocentesis, two after termination, and one at spontaneous abortion. Complete follow up data were available for the first 250 patients, among whom nine pregnancies (3.6%) ended in spontaneous abortion before the 20th week. There were no false negative findings. Seventy additional chromosome studies were performed because of failure of chorionic villi sampling or equivocal results, or for confirmation. Counselling before chorionic villi sampling should include the possibility that subsequent amniocentesis may be needed should mosaicism or other unexpected abnormalities be found. The success rate and accuracy of karyotyping chorionic villi samples by the direct method are acceptable but distinctly less than those of karyotyping cultured amniotic fluid cells.