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Query: UMLS:C0037315 (sleep apnea)
 8,000 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In postnatal infants, there is similarity between the time course of transient gonadal steroid secretion and the age-related incidence of sudden infant death syndrome (SIDS). The cause of death in SIDS is generally thought to be a ventilatory arrest, but the mechanism responsible for such an event remains unknown. Testosterone has been demonstrated to depress ventilatory drive and increase sleep apnea in adult men. We tested the hypothesis that the gonadal steroid testosterone depresses infant ventilatory drive during sleep. Three newborn male infant primates were gonadectomized after birth. Ventilation was observed and quantified for each animal during completely natural unencumbered sleep by plethysmography for an average of 16 wk. Ventilatory patterns were recorded, and ventilatory drive was challenged with hypercapnia and hypoxia during quiet sleep on the night before and the night after testosterone administration. Hypercapnic ventilatory drive during sleep was significantly depressed by an average of 33.6% on the night after compared with the night before testosterone administration. Depression of the response to hypercapnia after testosterone was not accompanied by any change in resting minute ventilation measured during quiet sleep. Hypoxic ventilatory drive, incidence of apneic events, and length of apnea were not different after testosterone. The effects of injecting a placebo on ventilatory patterns and drive were tested by giving the placebo to all animals on several test weeks. Placebo injections produced no significant change in any measured parameters. These results support the hypothesis that testosterone depresses hypercapnic ventilatory drive during sleep in the infant primate.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Depression of hypercapnic ventilatory drive by testosterone in the sleeping infant primate. 804 60

'Andropause', like menopause, has received significant attention in recent years. It results in a variety of symptoms experienced by the elderly. Many of these symptoms are nonspecific and vague. For this reason, many authors have questioned the value of androgen replacement in this population. Also in dispute is the normal cutoff level for testosterone beyond which therapy should be initiated, and whether to measure free or total testosterone. Testosterone levels decline with age, with the lowest level seen in men older than 70 years. This age-related decline in testosterone levels is both central (pituitary) and peripheral (testes) in origin. With aging, there is also a loss of circadian rhythm of testosterone secretion and a rise in sex hormone binding globulin (SHBG) levels. Total testosterone level is the best screening test for patients with suspected hypogonadism. If the total testosterone concentration is low, free testosterone levels should be obtained. Prostate cancer remains an absolute contraindication to androgen therapy. Testosterone replacement results in an improvement in muscle strength and bone mineral density. Similar effects are observed on the haematopoietic system. Data on cognition and lipoprotein profiles are conflicting. Androgen therapy can result in polycythemia and sleep apnoea. These adverse effects can be deleterious in men with compromised cardiac reserve. We recommend that elderly men with symptoms of hypogonadism and a total testosterone level <300 ng/dl should be started on testosterone replacement. This review discusses the pros and cons of testosterone replacement in hypogonadal elderly men and attempts to answer some of the unanswered questions. Furthermore, emphasis is made on the regular follow-up of these patients to prevent the development of therapy-related complications.
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PMID:Risks versus benefits of testosterone therapy in elderly men. 1049 72

Androgen replacement therapy (ART) is usually life-long, and should only be started after androgen deficiency has been proven by hormone assays. The therapeutic goal is to maintain physiological testosterone levels. Testosterone rather than synthetic androgens should be used. Oral 17 alpha-alkylated androgens are hepatotoxic and should not be used for ART. There is no indication for androgen therapy in male infertility. Although androgen deficiency is an uncommon cause of erectile dysfunction, all men presenting with erectile dysfunction should be evaluated for androgen deficiency. If androgen deficiency is confirmed, investigation for the underlying pathological cause is required. Contraindications to androgen therapy are prostate and breast cancer. Precautions include using lower starting doses for older men and induction of puberty. Intramuscular injections should be avoided in men with bleeding disorders. Androgen-sensitive epilepsy, migraine, sleep apnoea, polycythaemia or fluid overload need to be considered. Competitive athletes should be warned about the risks of disqualification. ART should be initiated with intramuscular injections of testosterone esters, 250 mg every two weeks [corrected]. Maintenance requires tailoring treatment modality to the patient's convenience. Modalities currently available include testosterone injections, implants, or capsules. Choice depends on convenience, cost, availability and familiarity. There is no convincing evidence that, in the absence of proven androgen deficiency, androgen therapy is effective and safe for older men per se, in men with chronic non-gonadal disease, or for treatment of non-specific symptoms. Until further evidence is available, such treatment cannot be recommended.
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PMID:Use, misuse and abuse of androgens. The Endocrine Society of Australia consensus guidelines for androgen prescribing. 1077 94

Androgen therapy may precipitate obstructive sleep apnea in men. Despite increasing androgen use in older men, few studies have examined sleep and breathing. Randomized, double-blind, placebo-controlled studies examining effects of testosterone simultaneously on sleep, breathing, and function in older men are not available. Seventeen community-dwelling healthy men over the age of 60 yr were randomized to receive three injections of im testosterone esters at weekly intervals (500 mg, 250 mg, and 250 mg) or matching oil-based placebo and then crossed over to the other treatment after 8 wk of washout. Polysomnography, anthropometry, and physical, mental, and metabolic function were assessed at baseline and after each treatment period. Testosterone treatment reduced total time slept ( approximately 1 h), increased the duration of hypoxemia ( approximately 5 min/night), and disrupted breathing during sleep (total and non-rapid eye movement respiratory disturbance indices both increased by approximately seven events per hour) (all P < 0.05). Despite expected effects on body composition (increase in total and lean mass, reduction in fat mass, P < 0.05, bioimpedance method), upper airway dimensions did not change (acoustic reflectometry). Driving ability (computer simulation), physical activity (accelerometry, Physical Activity Scale in the Elderly), quality of life (SF36, Functional Outcomes of Sleep Questionnaire), mood (Profile of Mood States Questionnaire), sleepiness (Epworth, Stanford scales), and insulin resistance (homeostasis model) also were not changed by treatment. Short-term administration of high-dose testosterone shortens sleep and worsens sleep apnea in older men but did not alter physical, mental, or metabolic function. These changes did not appear to be due to upper airway narrowing. Further study of longer-term lower-dose androgen therapy on sleep and breathing is needed to evaluate its safety in older men.
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PMID:The short-term effects of high-dose testosterone on sleep, breathing, and function in older men. 1291 43

Despite intensive research on testosterone therapy for older men, important questions remain unanswered. The evidence clearly indicates that many older men display a partial androgen deficiency. In older men, low circulating testosterone is correlated with low muscle strength, with high adiposity, with insulin resistance and with poor cognitive performance. Testosterone replacement in older men has produced benefits, but not consistently so. The inconsistency may arise from differences in the dose and duration of testosterone treatment, as well as selection of the target population. Generally, studies reporting anabolic responses to testosterone have employed higher doses of testosterone for longer treatment periods and have targeted older men whose baseline circulating bioavailable testosterone levels were low. Most studies of testosterone replacement have reported anabolic that are modest compared to what can be achieved with resistance exercise training. However, several strategies currently under evaluation have the potential to produce greater anabolic effects and to do so in a safe manner. At this time, testosterone therapy can not be recommended for the general population of older men. Older men who are hypogonadal are at greater risk for the catabolic effects associated with a number of acute and chronic medical conditions. Future research is likely to reveal benefits of testosterone therapy for some of these special populations. Testosterone therapy produces a number of adverse effects, including worsening of sleep apnea, gynecomastia, polycythemia and elevation of PSA. Efficacy and adverse effects should be assessed frequently throughout the course of therapy.
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PMID:Testosterone replacement therapy for older men. 1822 56

Testosterone seems to play a role in the pathophysiology of OSAS but the mechanisms are not yet well defined. Research of this relationship has focused on two main assumptions: first case support the emergence of OSAS or augmentation of OSAS severity in men treated with testosterone for symptomatic hypogonadism; the second hypothesis suggest that serum testosterone deficiency is due to hypoxia and microarousals generated by OSAS with direct impact on hypothalamic-pituitary-gonadal axis. The correlation between sleep apnea and androgenic disorders should be considered in the light of the intervention of many other factors which can act as confounding factors: age, obesity and other associated pathologies (chronic lung disease, smoking status). Many studies conducted so far on this interrelation (sleep apnea, endocrine system) have ignored these factors. In most cases CPAP (continuous positive airway pressure) therapy revert low serum testosterone levels to normal levels. Depressive status and fatigue, as OSAS consequences associated with hypogonadism have been reported in the literature and may have clinically significant aspects due to summary effect, with notable improvement after CPAP therapy avoiding adverse effects of hormonal or antidepressant treatment. The clinical implications and major consequences of association between androgen dysfunction and sleep apnea syndrome require a correct management in the recognition and treatment of obstructive sleep apnea syndrome associated with comorbidities.
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PMID:[Association between the serum level of testosterone and other comorbidities in obstructive sleep apnea]. 2278

Testosterone deficit syndrome is a clinical and biochemical syndrome associated with advanced age and characterized by some symptomsassociated with serum testosterone levels deficiency, which may result in a decrease of quality of life and negatively affect the function of multiple organs or systems. Clinical guidelines recommend testosterone replacement therapy (TRT) in patients with testosterone decrease that associate muscle mass and strength loss, lumbar spinal column bone density decrease, or libido and erection decrease. Contraindications for treatment would include active prostate cancer or without treatment, PSA >4 ng/ml waiting for diagnostic workup, breast cancer, severe sleep apnea, infertility, hematocrit over 50% or severe lower urinary tract symptoms secondary to benign prostatic hypertrophy. In certain situations there is still great controversy, without enough evidence to establish an action. References in case of patientstreated with brachytherapy or radiotherapy are unspecific: they only recommend caution in the treatment with TRT in these patients and strict monitoring of the possible recurrence. In our opinion, low-intermediate risk prostate cancer patients treated with radiotherapy only, without evidence of residual or recurrent disease, are candidates for TRT if symptoms justify it, leaving a free period of never less than one year after nadir (or 24 months after the end of therapy) which guarantees, on the possible means, the absence of biochemical or clinical recurrence,with strict follow up of clinical and biochemical usual parameters (hematocrit, hemoglobin, DRE, PSA).
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PMID:[Patient with testosterone deficit syndrome after external beam radiotherapy]. 2404 25

Epidemiological studies have demonstrated that prevalence of hypogonadism in old males increases with every additional decade of life. These males present various symptoms including decrease of sexual function, decrease of cognitive function, altered lipid profile, increased visceral adiposity, changes in bone density and muscular strength secondary to atrophy. Currently, testosterone injections and gel preparations are the most used. Testosterone replacement therapy provides significant symptomatic improvements for men with late start hypogonadism. Long-term benefits and risks of testosterone replacement therapy will be more evident when testosterone effects are studied on all health related parameters over a prolonged period of time. There is a large ongoing multicentric randomized clinical trial sponsored by NIH for testosterone control in old men with low testosterone levels. Its results may give answers to the possible benefits and risks of testosterone replacement in aging males. If an aging male is diagnosed as late-start hypogonadism, the urologist should discuss with the patient potential benefits and risks of testosterone therapy. Aging males with significant erythrocytosis, untreated sleep apnea, prostate cancer and high risk of cardiovascular events must be excluded from testosterone replacement therapy. Currently, there are not enough evidences to clearly state that the benefits of testosterone replacement therapy in aging males are better than the risks of this treatment. A general recommendation cannot be given that testosterone replacement therapy may be applied to all aging males with low testosterone levels independently of significant signs or symptoms.
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PMID:[Testosterone deficit syndrome in the old male]. 2404 27

Testosterone deficit syndrome (TDS) is a clinical and biochemical syndrome associated with advanced age and characterized by some typical symptoms and decrease in serum testosterone levels, which can affect multiple organs and systems, deteriorating the quality of life of the males who suffer it. Due to the low specificity of the clinical picture, as well as that of the commonly used questionnaires, when there is a diagnostic suspicion, serum testosterone determination is necessary, without a current universally accepted determination method. The increased survival of males in the western world and their demand of a better quality of life,including the preservation of sexual activity, up to increasingly more advanced ages: together with the appearance of new ways of testosterone delivery, make this entity, clinical-biochemical, acquirean increasingly greater importance. From a therapeutic point of view, testosterone replacement therapy has precise indications, with individualized evaluation in each patient on the basis of risk/benefit, and with an adequate, well defined follow up, that will allow the control of possible adverse events. TRT is recommended in patients with diminished testosterone associated with muscle mass and strength loss, decrease of bone density of the lumbar spine or diminished libido and quality of erection. Contraindications for therapy would include active or non treated prostate cancer, PSA >4 ng/ml before evaluation, breast cancer, severe sleep apnea, infertility, hematocrit over 50% or severe LUTS due to BPH.
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PMID:[Current recommendations about the diagnosis and treatment of testosterone deficit syndrome: Clinical guidelines]. 2404 34

With increasing modernization and urbanization of Asia, much of the future focus of the obesity epidemic will be in the Asian region. Low testosterone levels are frequently encountered in obese men who do not otherwise have a recognizable hypothalamic-pituitary-testicular (HPT) axis pathology. Moderate obesity predominantly decreases total testosterone due to insulin resistance-associated reductions in sex hormone binding globulin. More severe obesity is additionally associated with reductions in free testosterone levels due to suppression of the HPT axis. Low testosterone by itself leads to increasing adiposity, creating a self-perpetuating cycle of metabolic complications. Obesity-associated hypotestosteronemia is a functional, non-permanent state, which can be reversible, but this requires substantial weight loss. While testosterone treatment can lead to moderate reductions in fat mass, obesity by itself, in the absence of symptomatic androgen defi ciency, is not an established indication for testosterone therapy. Testosterone therapy may lead to a worsening of untreated sleep apnea and compromise fertility. Whether testosterone therapy augments diet- and exercise-induced weight loss requires evaluation in adequately designed randomized controlled clinical trials.
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PMID:Lowered testosterone in male obesity: mechanisms, morbidity and management. 2440 87


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