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

In contrast with women, who experience a complete and abrupt cessation of ovarian function during the menopause, aging men largely maintain their testicular androgen production. Nevertheless, most cross-sectional studies indicate that there is a partial decrease in testosterone levels with aging, although this has not been confirmed by other studies. The disparity among studies stems from differences in study design, patient numbers, assay techniques and inclusion criteria. Proposed mechanisms for an age-associated decline in testosterone production include: (i) defects in the hypothalamic-pituitary-testicular axis; (ii) an increase in sex hormone binding globulin levels; (iii) environmental factors; (iv) medication use; and (v) chronic illness. The potential beneficial effects of testosterone replacement therapy in hypogonadal men include increased bone density, increased muscle strength, an improved feeling of well-being and an improved metabolic profile. These benefits need to be weighted against the potential risks of androgen therapy, such as erythrocytosis, sleep apnoea, and the stimulation of benign prostatic hypertrophy or an occult prostate malignancy. Consequently, androgen replacement should be used with caution in elderly men with hypogonadism until the results of well-controlled prospective studies are available.
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PMID:Age-related changes in male gonadal function. Implications for therapy. 923 40

'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

Obesity, the result of combined genetic and environmental factors, is in recent decades one of the most frequent diseases and is encountered mainly in Europe and North America. In women it is associated with the risk of several diseases, such as diabetes mellitus, osteoarthritis, cardiovascular diseases, sleep apnoea syndromee, breast cancer, cancer of the uterus and also with impairment of reproductive functions. Already during the last century some observations confirmed that a very low or very high body weight is more frequently associated with disorders of the menstrual cycle (MC), infertility and poor reproductive capacity. However only during the last decades the pathophysiological and molecular mechanisms of this relationship were gradually elucidated. The main factors which influences the menstrual cycle in obesity are: impaired estrogen metabolism, changes in the concentration of sex hormone binding globulin, hyperinsulinaemia, and probably also leptin levels.
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PMID:[Obesity and disorders of the menstrual cycle]. 1206 Nov 86

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