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Altered fat distribution is associated with insulin resistance in HIV, but little is known about regional glucose metabolism in fat and muscle depots in this patient population. The aim of the present study was to quantify regional fat, muscle, and whole body glucose disposal in HIV-infected men with lipoatrophy. Whole body glucose disposal was determined by hyperinsulinemic clamp technique (80 mU* [m.sup.-2] * [min.sup.-1]) in 6 HIV-infected men and 5 age/weight-matched healthy volunteers. Regional glucose uptake in muscle and subcutaneous (SAT) and visceral adipose tissue (VAT) was quantified in fasting and insulin-stimulated states using 2-deoxy-[[sup.18F]]fluoro-D-glucose positron emission tomography. HIV-infected subjects with lipoatrophy had significantly increased glucose uptake into SAT (3.8 [+ or -] 0.4 vs. 2.3 [+ or -] 0.5 [micro]mol * kg [tissue.sup.-1] * [min.sup.-1], P < 0.05) in the fasted state. Glucose uptake into VAT did not differ between groups. VAT area was inversely related with whole body glucose disposal, insulin sensitivity, and muscle glucose uptake during insulin stimulation. VAT area was highly predictive of whole body glucose disposal ([r.sup.2] = 0.94, P < 0.0001). This may be mediated by adiponectin, which was significantly associated with VAT area (r = -0.75, P = 0.008), and whole body glucose disposal (r = 0.80, P = 0.003). This is the first study to directly demonstrate increased glucose uptake in subcutaneous fat of lipoatrophic patients, which may partially compensate for loss of SAT. Furthermore, we demonstrate a clear relationship between VAT and glucose metabolism in multiple fat and muscle depots, suggesting the critical importance of this depot in the regulation of glucose and highlighting the significant potential role of adiponectin in this process. positron emission tomography; adipose tissue; insulin resistance; human immunodeficiency virus-lipodystrophy

Background: Substantial loss of muscle mass occurs among men with AIDS wasting.Objective: To investigate the independent effects of testosterone therapy and progressive resistance training in eugonadal men with AIDS wasting.Design: Randomized, controlled trial.Setting: University hospital.Patients: 54 eugonadal men with AIDS wasting (weight < 90% ideal body weight or weight loss > 10%).Intervention: In a 2 x 2 factorial design, patients were assigned to receive testosterone enanthate (200 mg/wk) or placebo injections and progressive resistance training (three times weekly) or no training for 12 weeks.Measurements: Cross-sectional muscle area and other indices of muscle mass.Results: Cross-sectional muscle area increased in response to training compared with nontraining (change in arm muscle mass, 499 +/- 349 mm2 vs. 206 +/- 264 mm2 [P = 0.004]; change in leg muscle mass, 1106 +/- 854 mm2 vs. 523 +/- 872 mm2 [P = 0.045]) and in response to testosterone therapy compared with placebo (change in arm muscle mass, 512 +/- 371 mm2 vs. 194 +/- 215 mm2 [P< 0.001]; change in leg muscle mass, 1,236 +/- 881 mm2 vs. 399 +/- 729 mm2 [P = 0.002]). Levels of high-density lipoprotein cholesterol decreased in response to testosterone therapy compared with placebo (-0.03 +/- 0.13 mmol/L vs. 0.05 +/- 0.13 mmol/L [-1 +/- 5 mg/dL vs. 2 +/- 5 mg/dL]; P= 0.011) and increased in response to training compared with nontraining (0.05 +/- 0.13 mmol/L vs. 0.00 +/- 0.16 mmol/L [2 +/- 5 mg/dL vs. 0 +/- 6 mg/dL]; P = 0.052).Conclusions: In contrast to anabolic therapies that may have adverse effects on metabolic variables, supervised exercise effectively increases muscle mass and is associated with significant positive health benefits in eugonadal men with AIDS wasting. [ABSTRACT FROM AUTHOR]

Context: Antiretroviral therapy can be associated with visceral adiposity and metabolic complications, increasing cardiovascular risk, and reduced growth hormone (GH) secretion may be a contributing factor.Objective: To investigate the effects of low-dose physiological GH administration on body composition, glucose, and cardiovascular parameters in patients with human immunodeficiency virus (HIV) having abdominal fat accumulation and relative GH deficiency.Design, Setting, and Patients: A randomized, double-blind, placebo-controlled trial of 56 patients with HIV, abdominal fat accumulation, and reduced GH secretion (peak GH <7.5 ng/mL) conducted at a US academic medical center between November 2003 and October 2007.Intervention: Patients were randomly assigned to receive either subcutaneous GH or matching placebo titrated to the upper quartile of normal insulinlike growth factor 1 (IGF-1) range for 18 months. Starting dose was 2 microg/kg/d and increased to maximum dose of 6 microg/kg/d (average dose, 0.33 mg/d).Main Outcome Measures: Change in body composition assessed by computed tomographic scan and dual-energy x-ray absorptiometry. Secondary outcomes included glucose, IGF-1, blood pressure (BP), and lipids. Treatment effect was the difference in the change between GH and placebo groups, using all available data.Results: Fifty-five patients (26 with GH and 29 with placebo) were included in the safety analyses and 52 patients (25 with GH and 27 with placebo) were included in the efficacy analyses. Visceral adipose tissue area (treatment effect [last-value-carried-forward analysis {n = 56}, -19 cm(2); 95% confidence interval {CI}, -37 to -0.3 cm(2)], -19 cm(2); 95% CI, -38 to -0.5 cm(2); P = .049); trunk fat (-0.8 kg; 95% CI, -1.5 to -0.04 kg; P = .04); diastolic BP (-7 mm Hg; 95% CI, -11 to -2 mm Hg; P = .006); and triglycerides (-7 mg/dL, P = .002) improved but 2-hour glucose levels on glucose tolerance testing increased in the GH group vs the placebo group (treatment effect, 22 mg/dL; 95% CI, 6-37 mg/dL; P = .009). The IGF-1 levels increased (treatment effect, 129 ng/mL; 95% CI, 95-164 ng/mL; P < .001). Adverse events were not increased for GH vs placebo (23%; 95% CI, 9%-44% vs 28%; 95% CI, 13%-47%; P = .70).Conclusions: In HIV-associated abdominal fat accumulation and relative GH deficiency, low-dose GH received for 18 months resulted in significantly reduced visceral fat and truncal obesity, triglycerides, and diastolic BP, but 2-hour glucose levels on glucose tolerance testing were increased.Trial Registration: clinicaltrials.gov Identifier: NCT00100698. [ABSTRACT FROM AUTHOR]

BACKGROUND: Antiretroviral therapy (ART)-associated lipoatrophy involves mitochondrial dysfunction. Iron metabolism impacts mitochondrial function and oxidative stress. Mitochondrial haplogroups and hemochromatosis gene (HFE) polymorphisms have been associated with ART-induced neuropathy. We assessed relationships between these variants and lipoatrophy. METHODS: The AIDS Clinical Trials Group 384 study randomized ART-naive individuals to receive didanosine-stavudine or zidovudine-lamivudine, combined with efavirenz and/or nelfinavir. Substudy A5005s evaluated fat distribution by dual-energy X-ray absorptiometry (DEXA). We characterized HFE polymorphisms 845G>A and 187C>G and European mitochondrial haplogroups in A5005s participants who consented to genetic analyses. RESULTS: Among 96 participants (58% were white, and 10% were female) with baseline and 48 or 64 week DEXA data, the median limb fat change was -8.8% (interquartile range, -28.7% to +15.6%). HFE 187C/G heterozygotes (n = 23) had less limb fat loss than 187C/C homozygotes (n = 71) (+6.1% vs. -12.5%; P = .02) and were less likely to develop lipoatrophy after adjustment for age, sex, race, and ART randomization (odds ratio, 0.31; 95% confidence interval, 0.10-0.95; P = .04). Among non-Hispanic white participants, median limb fat change was +26.1% among 5 participants with mitochondrial haplogroup J, compared with -9.7% among 49 participants with other mitochondrial haplogroups (P = .07). CONCLUSIONS: HFE 187C>G and, possibly, mitochondrial haplogroup J gave relative protection against lipoatrophy during ART in A5005s. These associations should be replicated in other studies. Copyright © 2008 Infectious Diseases Society of America [ABSTRACT FROM AUTHOR]

Objectives Adipose dysregulation, dyslipidemia, and insulin resistance are hallmarks of HIV-related lipodystrophy. The precise mechanisms behind these disturbances are unknown. In HIV-infected patients, we previously demonstrated a strong relationship between lipodystrophy and levels of adiponectin, an adipose peptide implicated in regulation of glucose and lipid metabolisms. In this study we investigated the effect of HIV on adipocytes, to determine whether HIV can directly infect adipocytes and/or alter the regulation and secretion of the adipocyte-derived hormone adiponectin. Methods Human subcutaneous preadipocytes and adipocytes were exposed to HIV-1 under various conditions. Adiponectin was measured in supernatants and cell lysates. Results Although adipocytes expressed CD4, the major HIV receptor, they could not be infected in vitro. However, exposure to HIV dramatically increased the secretion of adiponectin from human adipocytes, in the absence of infection. This was exacerbated with sustained exposure to HIV in a transwell assay. Further, human peripheral mononuclear cells also produced adiponectin, but this was largely dependent upon T-cell activation. Conclusions We propose that the stimulation of adiponectin production by HIV can perturb adiponectin regulation, leading to substantially decreased levels upon viral suppression by antiretroviral therapy. These data suggest a potential molecular mechanism of adiponectin regulation in HIV-infected patients. [ABSTRACT FROM AUTHOR]

Context: Reduced growth hormone (GH) concentrations are observed in men with human immunodeficiency virus (HIV) lipodystrophy.Objective: To investigate the effects of growth hormone-releasing hormone (GHRH), a GH secretagogue, in treatment of HIV lipodystrophy.Design, Setting, and Participants: Randomized, double-blind, placebo-controlled trial conducted at a research center in the United States between October 2002 and June 2003 and enrolling 31 HIV-infected men aged 18 to 60 years with evidence of lipodystrophy.Interventions: Participants were assigned to receive GHRH (1 mg subcutaneously twice daily) or placebo for 12 weeks.Main Outcome Measures: The primary outcome was change in concentrations of insulin-like growth factor 1 (IGF-1) to detect overall change in GH levels in response to GHRH. Secondary end points included body composition by dual-energy x-ray absorptiometry and computed tomography, lipodystrophy ratings, and levels of glucose, insulin, and lipids.Results: Mean (SD) IGF-1 concentrations increased significantly in the GHRH group vs the placebo group (104 [110] ng/mL vs 6 [44] ng/mL, P =.004). Lean body mass significantly increased in the GHRH group vs the placebo group (0.9 [1.3] kg vs -0.3 [1.7] kg, P =.04), trunk fat significantly decreased (-0.4 [0.7] kg vs 0.2 [0.6] kg, P =.03), and the ratio of trunk to lower extremity fat improved significantly (-0.22 [0.32] vs 0.14 [0.29], P =.005). Abdominal visceral fat was reduced (-19.2 [36.6] cm2 vs 2.3 [24.3] cm2, P =.07) and the ratio of abdominal visceral fat to abdominal subcutaneous fat improved significantly more in the GHRH group (-0.19 [0.28] vs 0.07 [0.27], P =.02). Both physician and patient rating of lipodystrophy in the arms, legs, and abdomen also improved significantly. Levels of glucose, insulin, and lipids did not change significantly.Conclusions: GHRH was well tolerated and effectively increased levels of IGF-1 in HIV-infected men with lipodystrophy. Total and regional body composition improved in response to GHRH, with increased lean mass and reduced truncal and visceral fat. Use of GHRH may potentially be a beneficial treatment strategy for this population. [ABSTRACT FROM AUTHOR]

Background: Patients with HIV infection who are treated with antiretroviral agents often lose subcutaneous fat and have metabolic abnormalities, including insulin resistance and reduced adiponectin levels, which may be related to disrupted subcutaneous adipogenesis and altered peroxisome proliferator-activated receptor-gamma signaling.Objective: To investigate the effects of rosiglitazone (4 mg/d), a peroxisome proliferator-activated receptor-gamma agonist, in HIV-infected men and women with hyperinsulinemia and lipoatrophy.Design: A randomized, double-blind, placebo-controlled, 3-month study.Setting: University hospital.Patients: 28 HIV-infected men and women with hyperinsulinemia and lipoatrophy.Measurements: Insulin sensitivity measured by euglycemic hyperinsulinemic clamp testing; subcutaneous leg fat area measured by computed tomography; adiponectin, free fatty acid, and lipid levels; and safety variables.Results: Rosiglitazone, when compared with placebo, improved insulin sensitivity (mean [+/-SD] change, 1.5 +/- 2.1 mg of glucose/kg of lean body mass per minute vs. -0.4 +/- 1.6 mg/kg per minute; P = 0.02), increased adiponectin levels (mean [+/-SD], 2.2 +/- 2.2 micro g/mL vs. 0.1 +/- 1.1 microg/mL; P = 0.006), and reduced free fatty acid levels (mean [+/-SD], -0.09 +/- 0.1 mmol/L vs. 0.01 +/- 0.1 mmol/L; P = 0.02). Mean percentage (+/-SD) of body fat (1.38% +/- 3.03% vs. -0.83% +/- 2.76%; P = 0.03) and subcutaneous leg fat area (2.3 +/- 8.4 cm2 vs. -0.9 +/- 1.9 cm2; P = 0.02) increased significantly with rosiglitazone compared with placebo. Mean total cholesterol levels (+/-SD) also increased with rosiglitazone compared with placebo (0.6 +/- 1.0 mmol/L [25 +/- 37 mg/dL] vs. -0.4 +/- 0.6 mmol/L [-15 +/- 25 mg/dL]; P = 0.007).Limitations: The study was relatively small and of short duration.Conclusions: The authors demonstrated positive effects of rosiglitazone on lipoatrophy; insulin sensitivity; and metabolic indices, including adiponectin levels, in HIV-infected patients with lipoatrophy and insulin resistance. Peroxisome proliferator-activated receptor-gamma agonists may correct the metabolic abnormalities associated with disrupted adipogenesis in this population. Further studies must determine the clinical utility of such agents in HIV-infected patients. [ABSTRACT FROM AUTHOR]

Background: Anorexia nervosa is highly prevalent among young women.Objective: To determine prevalence and predictive factors for regional bone loss.Design: Prospective cohort analysis.Setting: University hospital.Patients: 130 women with anorexia nervosa.Measurements: Dual-energy x-ray absorptiometry.Results: The prevalence of osteopenia (-1.0 SD >/= T-score > -2.5 SD) and osteoporosis (T-score Conclusions: Bone mineral density is reduced at several skeletal sites in most women with anorexia nervosa. Weight, but not estrogen use, is a significant predictor of BMD in this population at all skeletal sites. [ABSTRACT FROM AUTHOR]

BACKGROUND: Lean body mass is an important predictor of survival and functional status in patients with AIDS wasting. The bias between different techniques for assessing body composition in AIDS wasting is not known. DESIGN: We compared total body potassium (TBK) with fat-free mass (FFM) determined by dual-energy X-ray absorptiometry (DXA), bioelectrical impedance analysis (BIA), and skinfold-thickness measurement (SKF) in 132 patients (63 men, 69 women) with AIDS wasting (weight < 90% of ideal body weight, or weight loss > 10% of original, or both). None of the subjects exhibited clinical lipodystrophy. Comparisons were made by using different BIA equations. RESULTS: Lean body mass determined by DXA was highly correlated with TBK in men (r = 0.79, P: < 0.0001) and women (r = 0.84, P: < 0.0001). FFM(BIA) and FFM(DXA) were significantly different (P: < 0.01 in men and P: < 0.0001 in women). The difference between FFM(DXA) and FFM(BIA) was significantly greater with greater weight and body fat, particularly in HIV-infected women (r = -0.39, P: = 0.001 for weight; r = -0.60, P: < 0.0001 for fat). The comparability of FFM and fat mass determined by DXA and BIA was dependent on the specific BIA equation used. Among men, no single BIA equation was more highly predictive of fat mass and FFM in comparison with DXA. CONCLUSIONS: The differences between DXA, BIA, and SKF in the determination of fat mass and FFM are significant in patients with AIDS wasting. BIA overestimates FFM compared with DXA in those with greater body fat. Standard BIA equations may not accurately estimate FFM and fat mass in men and women with AIDS wasting. Copyright © 2000 American Society for Clinical Nutrition [ABSTRACT FROM AUTHOR]

Context: A syndrome of lipodystrophy, characterized by fat redistribution and insulin resistance, has been estimated to affect the majority of human immunodeficiency virus (HIV)-infected individuals who are treated with combination antiretroviral therapy. There are no proven therapies for the metabolic disturbances associated with HIV lipodystrophy syndrome.Objective: To determine the safety and efficacy of metformin therapy in HIV-infected patients with fat redistribution and abnormal glucose homeostasis.Design and Setting: Randomized, double-blind, placebo-controlled pilot study conducted in a university hospital between December 1998 and January 2000.Patients: Twenty-six HIV-infected, nondiabetic patients with fat redistribution and abnormal oral glucose tolerance test (OGTT) results, hyperinsulinemia, or both.Interventions: Patients were randomly assigned to receive metformin, 500 mg twice daily (n = 14), or identical placebo (n = 12), for 3 months.Main Outcome Measures: Insulin area under the curve (AUC), calculated 120 minutes following a 75-g OGTT at baseline vs at 3-month follow-up and compared between treatment groups.Results: Patients treated with metformin demonstrated significant reductions in mean (SEM) insulin AUC 120 minutes after OGTT (-2930 [912] vs -414 [432] microIU/mL [-20349 6334 vs -2875 3000 pmol/L]; P =.01), weight (-1.3 [0.6] vs 1.1 [0.4] kg; P =.005), and diastolic blood pressure (-5 [4] vs 5 [2] mm Hg; P =.009) vs controls, respectively. Metformin therapy was associated with a decrease in visceral abdominal fat (VAT; -1115 [819] vs 1191 [699] mm(2); P =.08) and a proportional reduction in subcutaneous abdominal fat (SAT); the VAT-SAT ratio was unchanged in metformin-treated vs placebo-treated patients. No increase in lactate or liver transaminase levels was observed with metformin treatment. Mild diarrhea was the most common adverse effect of metformin. No patient discontinued therapy because of adverse effects.Conclusions: This study suggests that a relatively low dosage of metformin reduces insulin resistance and related cardiovascular risk parameters in HIV-infected patients with lipodystrophy. JAMA. 2000;284:472-477 [ABSTRACT FROM AUTHOR]

Background: Untreated Cushing disease historically has a high mortality rate, but the long-term survival of patients with Cushing disease after transsphenoidal surgery has not been reported.Objective: To determine long-term mortality rate in patients who are treated for Cushing disease with current management techniques.Design: Retrospective case series.Setting: Tertiary care center.Patients: 161 patients (32 men and 129 women; mean age, 38 years) who were treated for Cushing disease between 1978 and 1996.Intervention: Transsphenoidal adenomectomy and as-needed adjunctive therapy.Measurement: Record review with follow-up interview.Results: The cure rate for patients with microadenomas who had no previous therapy was 90% (123 of 137). No perioperative deaths occurred (0 of 193 procedures [95% CI, 0.0% to 1.9%]). Follow-up data (mean, 8.7 years) were obtained for 99% of patients (159 of 161). Six patients died. The 5- and 10-year survival rates were 99% (CI, 97% to 100%) and 93% (CI, 88% to 99%), respectively. Survival was similar to that seen in an age- and sex-matched sample that was based on U.S. population data (standardized mortality ratio, 0.98 [CI, 0.44 to 2.2]; P > 0.2).Conclusion: Survival of patients treated for Cushing disease with current management techniques between 1978 and 1996 was better than the poor survival historically associated with this disorder. [ABSTRACT FROM AUTHOR]