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Query: UMLS:C0021051 (immunodeficiency)
 71,517 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Multiple endocrine and metabolic consequences of human immunodeficiency virus (HIV) infection exist that may contribute to bone loss in men with the acquired immune deficiency syndrome (AIDS) wasting syndrome. Recent studies suggest that anabolic strategies can increase lean body mass in men with AIDS wasting. Prior studies have not examined the effects of anabolic agents on bone mineral density (BMD) or bone turnover in these men. To determine the effects of testosterone and progressive resistance training on BMD and bone turnover in eugonadal men with AIDS wasting, we randomly assigned 54 eugonadal men with AIDS wasting (weight < 90% IBW or weight loss >10% from preillness baseline) to receive either testosterone enanthate (200 mg/week, im) or placebo and to progressive resistance training (3 times/week) or no training in a 2 x 2 factorial study design for 3 months. The BMD of the lumbar spine, proximal femur, and total body; lean body mass; and fat mass were measured by dual energy x-ray absorptiometry. Total body scans were repeated after 12 weeks of therapy. Baseline bone turnover and BMD were compared with those in 35 age-matched healthy non-HIV-infected control subjects. Compared with controls, lumbar spine BMD (1.021 +/- 0.018 vs. 1.084 +/- 0.025 g/cm(2); P = 0.04) and total hip BMD (0.951 +/- 0.017 vs. 1.070 +/- 0.019 g/cm(2); P < 0.0001) were reduced in men with AIDS wasting. T-scores were lower in men with AIDS wasting at the lumbar spine (-0.62 +/- 0.17 vs. -0.07 +/- 0.23, P = 0.05) and total hip (-0.65 +/- 0.11 vs. +0.20 +/- 0.014, P < 0.0001). Total hip T scores were less than -1.0 in 33% of men with AIDS wasting. Neither the use of protease inhibitors nor the duration of protease inhibitors use correlated with BMD. Serum osteocalcin levels were lower (3.63 +/- 0.29 vs. 4.54 +/- 0.31 nmol/L; P < 0.04) and urinary N-telopeptide excretion was higher (45.4 +/- 4.5 vs. 26.8 +/- 3.0 nmol BCE/mmol creatinine; P = 0.004) in men with AIDS wasting than in controls. Lumbar spine BMD, as assessed on regional total body dual energy x-ray absorptiometry scan, increased over the 12-week treatment period in response to testosterone (+2.4 +/- 1.3 vs. -1.3 +/- 1.0%, testosterone vs. placebo, respectively; P = 0.02), but not in response to training (+0.8 +/- 1.0 vs. +0.4 +/- 1.3%, training vs. no training; P = 0.70). Lumbar spine and total hip BMD are reduced in eugonadal men with AIDS wasting. Biochemical markers of bone turnover suggest that bone formation and bone resorption are uncoupled in these men. Testosterone administration, but not resistance training, over 3 months increases lumbar spine BMD in eugonadal men with AIDS wasting.
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PMID:Osteopenia in eugonadal men with acquired immune deficiency syndrome wasting syndrome. 1134 1

The term "anabolic steroids" refers to testosterone derivatives that are used either clinically or by athletes for their anabolic properties. However, scientists have questioned the anabolic effects of testosterone and its derivatives in normal men for decades. Most scientists concluded that anabolic steroids do not increase muscle size or strength in people with normal gonadal function and have discounted positive results as unduly influenced by positive expectations of athletes, inferior experimental design, or poor data analysis. There has been a tremendous disconnect between the conviction of athletes that these drugs are effective and the conviction of scientists that they aren't. In part, this disconnect results from the completely different dose regimens used by scientists to document the correction of deficiency states and by athletes striving to optimize athletic performance. Recently, careful scientific study of suprapharmacologic doses in clinical settings - including aging, human immunodeficiency virus, and other disease states - supports the efficacy of these regimens. However, the mechanism by which these doses act remains unclear. "Anabolism" is defined as any state in which nitrogen is differentially retained in lean body mass, either through stimulation of protein synthesis and/or decreased breakdown of protein anywhere in the body. Testosterone, the main gonadal steroid in males, has marked anabolic effects in addition to its effects on reproduction that are easily observed in developing boys and when hypogonadal men receive testosterone as replacement therapy. However, its efficacy in normal men, as during its use in athletes or in clinical situations in which men are eugonadal, has been debated. A growing literature suggests that use of suprapharmacologic doses can, indeed, be anabolic in certain situations; however, the clear identification of these situations and the mechanism by which anabolic effects occur are unclear. Furthermore, the pharmacology of "anabolism" is in its infancy: no drugs currently available are "purely" anabolic but all possess androgenic properties as well. The present review briefly recapitulates the historic literature about the androgenic/anabolic steroids and describes literature supporting the anabolic activity of these drugs in normal people, focusing on the use of suprapharmacologic doses by athletes and clinicians to achieve anabolic effects in normal humans. We will present the emerging literature that is beginning to explore more specific mechanisms that might mediate the effects of suprapharmacologic regimens. The terms anabolic/androgenic steroids will be used throughout to reflect the combined actions of all drugs that are currently available.
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PMID:Anabolic steroids. 1201 55

Risk factors for hypoandrogenemia among low-weight, human immunodeficiency virus (HIV)-infected patients are not known. Testosterone levels of 69 HIV-infected women with low weight and weight loss were compared with levels for 25 healthy, age- and body mass index-matched control subjects. HIV-infected subjects were of low weight, with a mean (+/- standard deviation) weight loss of -17.6% +/- 9.7% from preillness maximum, and 42% of HIV-infected subjects had a body mass index of <20 kg/m(2). Forty-nine percent of the HIV-infected population versus 8% of the control population exhibited low free testosterone levels (P<.001). Among HIV-infected women, when we controlled for chronic hepatitis status, age, and time of blood sampling, weight loss of >10% of maximum weight was a significant predictor of low free testosterone levels. Free testosterone levels did not differ by drug class or antiretroviral regimen. In conclusion, decreased androgen levels are common among HIV-infected women reporting significant weight loss, independent of exposure to antiretroviral medications.
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PMID:Reduced testosterone levels in human immunodeficiency virus-infected women with weight loss and low weight. 1256 9

Low testosterone levels are common in both men and women with human immunodeficiency virus (HIV) infection and may contribute to loss of lean body mass and AIDS wasting. Causes of low testosterone levels are complex and may include chronic illness, HIV infection and its complications, medications used to treat HIV and opportunistic diseases, and normal aging-related declines. In the majority of studies addressing the use of testosterone treatment in HIV-infected patients, testosterone has been found to help prevent loss of lean body and muscle mass. Whether the combination of exercise and testosterone is more effective in preventing loss of lean body mass than either therapy alone is not yet clear and warrants further study. In addition to its effects on body composition, testosterone treatment results in improved mood and libido in HIV-infected women and increased bone mineral density in HIV-infected men. Testosterone may thus make a valuable contribution to the treatment of HIV-infected individuals. International Journal of Impotence Research (2003) 15, Suppl 4, S21-S25. doi:10.1038/sj.ijir.3901032
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PMID:Role of testosterone in maintaining lean body mass and bone density in HIV-infected patients. 1293 47

In spite of the widespread belief that testosterone supplementation increases the risk of atherosclerotic heart disease, evidence to support this premise is lacking. Although supraphysiological doses of testosterone, such as those used by athletes and recreational body builders, decrease plasma high-density lipoprotein (HDL) cholesterol concentrations, replacement doses of testosterone have had only a modest or no effect on plasma HDL in placebo-controlled trials. In epidemiological studies, serum total and free testosterone concentrations have been inversely correlated with intra-abdominal fat mass, risk of coronary artery disease, and type 2 diabetes mellitus. Testosterone administration to middle-aged men is associated with decreased visceral fat and glucose concentrations and increased insulin sensitivity. Testosterone infusion increases coronary blood flow. Similarly, testosterone replacement retards atherogenesis in experimental models of atherosclerosis. However, the long-term risks and benefits of testosterone administration in human immunodeficiency virus-infected men with fat redistribution syndrome have not been studied in randomized clinical trials.
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PMID:Effects of testosterone administration on fat distribution, insulin sensitivity, and atherosclerosis progression. 1294 89

Testosterone therapy for postmenopausal women and women with surgical menopause, albeit controversial, is becoming more widespread. However, only limited data are available to support its use in premenopausal women. Androgens have important biological roles in young women, influencing bone and muscle mass, mood and well-being, and libido. Pathophysiological states affecting ovarian and adrenal function or both may result in androgen deficiency in premenopausal women. Young women with hypothalamic amenorrhea, premature ovarian failure, oophorectomy, premenstrual syndrome, acquired immunodeficiency wasting syndrome, adrenal insufficiency, and hypopituitarism may have testosterone deficiency. Young women with loss of libido may also have testosterone deficiency. Medications that may lead to testosterone insufficiency include oral estrogen, oral contraceptives, and corticosteroids. Testosterone deficiency in young women may be underdiagnosed because the symptoms generally are nonspecific and the measurement of total and free testosterone is inaccurate with commonly used techniques. Only a few studies investigating the effects of testosterone therapy have been performed thus far in premenopausal women. Long-term trials evaluating safety and effectiveness of testosterone therapy in premenopausal women are lacking. Common adverse effects include hirsutism and acne, which reverse with discontinuation of treatment. The availability of testosterone regimens specifically designed for women is expected to help maintain testosterone levels within the normal range and clarify whether the apparent beneficial effects of testosterone therapy are physiological or pharmacological.
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PMID:Testosterone therapy in premenopausal women. 1663 84

Testosterone increases fat-free mass (FFM) in men infected with human immunodeficiency virus (HIV), but its effects on muscle performance, physical function, mood, and quality of life are poorly understood. Sixty-one HIV-infected men with weight loss were randomized to receive weekly intramuscular injections of 300 mg of testosterone enanthate or placebo for 16 wk. The primary outcome of interest was physical function (walking speed, stair-climbing power, and load-carrying ability). Secondary outcome measures included body weight and composition, muscle performance, sexual function, mood, and quality of life. Serum nadir free and total testosterone levels increased (+188.0 +/- 29.6 and +720 +/- 86 ng/dl) in the testosterone, but not placebo, group. Testosterone administration was associated with increased FFM (2.8 +/- 0.5 kg), which was significantly greater than in the placebo group (P < 0.0001). Leg press strength increased significantly in testosterone-treated (P = 0.027), but not placebo-treated, men; the difference between groups was not significant. Other measures of muscle performance and physical function did not change significantly in either group. Men receiving testosterone demonstrated significantly greater improvements in mental health and quality-of-life scores than those receiving placebo and improvements in fatigue/energy and mood scores that were not significantly different from those receiving placebo. Sexual function scores did not change in either group. In HIV-infected men with weight loss, a supraphysiological dose of testosterone significantly increased FFM but did not improve self-reported or performance-based measures of physical function. Improvements in mood, fatigue, and quality-of-life measures in the testosterone group, although clinically important, need further confirmation.
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PMID:Effects of a supraphysiological dose of testosterone on physical function, muscle performance, mood, and fatigue in men with HIV-associated weight loss. 1885 50

Testosterone is involved in the development and expression of physiological, morphological and behavioural traits. High levels are often associated with high infection risk and/or intensity, suggesting a trade-off between sexual traits and immunity. Classically invoked mechanisms are immunological or behavioural, i.e., testosterone increases susceptibility or resistance to parasites via an impact on immunity or modulates behaviours involved in parasite transmission. However, studies report contrasted patterns. Given its modes of action and the diversity of host-parasite interactions, testosterone should not act similarly on all interactions. To reduce host and context diversity, we studied 3 viruses in the same cat population: the aggressively transmitted Feline Immunodeficiency virus (FIV), and the Feline Calicivirus (FCV) and Herpesvirus (FHV) both transmitted during friendly contacts. Testosterone had a strong effect on the probability of being positive to FIV whereas its effect was significantly weaker on FCV and FHV. These findings demonstrate that testosterone can be differentially associated with parasites of the same type (viruses). The difference we observed was consistent with a behavioural-mediated effect (increased aggressiveness), supporting the idea that the testosterone effect on infection risk is at least partially driven by behavioural mechanisms in our system. Further investigations (e.g., individual immunity measures) are required to confirm this hypothesis.
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PMID:Differential association between circulating testosterone and infection risk by several viruses in natural cat populations: a behavioural-mediated effect? 2328 19

Pharmacologic interventions for human immunodeficiency virus (HIV) wasting have been studied since the 1990s, but the results of these interventions have been difficult to compare because the studies used different HIV wasting definitions and assessed various patient outcomes. Thus, we performed a systematic review of the current literature to identify studies that evaluated pharmacologic management of HIV wasting and to compare and contrast treatment options. Further, we provide a comprehensive review of these treatment options and describe the definition of HIV wasting used in each study, the outcomes assessed, and whether antiretroviral therapy was used during the HIV wasting treatment. Literature searches of the PubMed/Medline (1946-2014) and Google Scholar databases were performed, and a review of the bibliographies of retrieved articles was performed to identify additional references. Only English-language articles pertaining to humans and HIV-infected individuals were evaluated. Thirty-six studies were identified that assessed pharmacologic interventions to treat HIV wasting. Appetite stimulants, such as megestrol acetate, have been shown to increase total body weight (TBW) and body mass index in HIV-infected patients with wasting. Studies evaluating dronabinol showed conflicting data on TBW increases, but the drug may have minimal benefit on body composition compared with other appetite stimulants. Testosterone has been shown to be effective in HIV wasting for those who suffer from hypogonadism. Recombinant human growth hormone has been evaluated for HIV wasting and has shown promising results for TBW and lean body mass increases. Thalidomide has been studied; however, its use is limited due to its toxicities. Although megestrol acetate and dronabinol are approved by the U.S. Food and Drug Administration (FDA) for the treatment of HIV wasting, it is important to recognize other comorbidities such as depression or hypogonadism that may contribute to the patient's appetite and weight loss. If a patient is diagnosed with hypogonadism and HIV wasting, testosterone would be a good therapeutic option. Although mirtazapine is not FDA approved for the management of HIV wasting, it has been shown to promote weight gain while treating depression symptoms. Mirtazapine may be a promising pharmacologic option in the management of HIV wasting and depression, but further research is needed.
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PMID:Pharmacologic management of human immunodeficiency virus wasting syndrome. 2478 95

Testosterone is derived from Leydig cells and exerts its effects on androgen receptors to influence growth, mood, voice, and several other bodily functions. As men age, their testosterone levels decline. Human immunodeficiency virus (HIV) infection has also been associated with lowered serum testosterone levels. Subtherapeutic levels of testosterone may lead to fatigue, loss of libido, and dysphoria. Exogenous replacement of testosterone can be accomplished by several modalities (oral, topical, injection), with each having distinct advantages and disadvantages. Even though testosterone replacement has become a popular medical intervention, recent reports have made the practice increasingly controversial. Several small retrospective investigations have recently associated testosterone replacement with an increased risk of cardiovascular complications. Replacement should be used sparingly until further conclusive data regarding the efficacy and safety of testosterone become available.
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PMID:Issues Surrounding Testosterone Replacement Therapy. 2780


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