Low-dose physiological growth hormone in patients with HIV and abdominal fat accumulation: a randomized controlled trial.

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.

Dietary fat intake and relationship to serum lipid levels in HIV-infected patients with metabolic abnormalities in the HAART era.

OBJECTIVE: To evaluate dietary intake and its relationship to lipid parameters in HIV-infected patients with metabolic abnormalities. METHOD: We prospectively determined dietary intake (4-day food records or 24-h recall) in 356 HIV-infected patients and 162 community-derived HIV-negative controls evaluated for metabolic studies between 1998-2005. Differences in dietary intake between HIV-infected patients and non-HIV-infected controls, in relation to the established 2005 USDA (United States Department of Agriculture) Recommended Dietary Guidelines, were determined. The relationship between dietary fat intake and serum lipid levels among HIV-infected individuals was also evaluated. RESULTS: Assessment of dietary intake in this group of HIV-infected patients demonstrated increased intake of total dietary fat (P < 0.05), saturated fat (P = 0.006), and cholesterol (P = 0.006) as well as a greater percentage of calories from saturated fat (P = 0.002) and from trans fat (P = 0.02), despite similar caloric intake to the control individuals. A significantly higher percentage of HIV-infected patients were above the 2005 USDA Recommended Dietary Guidelines for saturated fat (> 10%/day) (76.0% HIV vs. 60.9% controls, P = 0.003), and cholesterol (> 300 mg/day) (49.7% HIV vs. 37.9% controls, P = 0.04). Saturated fat intake was strongly associated with triglyceride level [triglyceride level increased 8.7 mg/dl (parameter estimate) per gram of increased saturated fat intake, P = 0.005] whereas total fat was inversely associated with triglyceride level [triglyceride level decreased 3.0 mg/dl (parameter estimate) per gram of increased total fat intake, P = 0.02] among HIV-infected individuals. CONCLUSIONS: Increased intake of saturated fat is seen and contributes to hypertriglyceridemia among HIV-infected patients who have developed metabolic abnormalities. Increased saturated fat intake should be targeted for dietary modification in this population.

Improved triglycerides and insulin sensitivity with 3 months of acipimox in human immunodeficiency virus-infected patients with hypertriglyceridemia.

CONTEXT: Metabolic abnormalities such as hypertriglyceridemia remain a challenge for optimizing long-term health in HIV-infected patients. OBJECTIVE: Elevation of free fatty acids (FFAs) may contribute to hyperlipidemia and insulin resistance in HIV. We evaluated the efficacy and safety of chronic inhibition of lipolysis in HIV-infected men and women with hypertrigyceridemia. We hypothesized that acipimox would lead to significant reductions in triglycerides and improved insulin sensitivity, compared with placebo. DESIGN: A 3-month, randomized, double-blind, controlled trial of acipimox (250 mg thrice daily) vs. placebo was conducted in 23 HIV-infected men and women with hypertriglyceridemia (>150 mg/dl), abnormal fat distribution, and no current lipid-lowering therapy. The primary outcome variable was triglyceride concentration, and insulin sensitivity measured by hyperinsulinemic euglycemic clamp was a secondary outcome. SETTING: The study was conducted at an academic medical center. RESULTS: Acipimox resulted in significant reductions in FFAs [mean change -0.38 (0.06) vs. 0.08 (0.06) mEq/liter with placebo, -68 vs. +17% change from mean baseline, P < 0.0001], decreased rates of lipolysis (P < 0.0001), and a median triglyceride decrease from 238 mg/dl at baseline to 190 mg/dl, compared with an increase from 290 to 348 mg/dl in the placebo group (P = 0.01). Acipimox improved insulin sensitivity [acipimox +2.31 (0.74) vs. placebo -0.21 (0.90) mg glucose per kilogram lean body mass per minute, or +31 vs. -2% change from mean baseline values, P = 0.04]. Improvements in insulin sensitivity were significantly correlated with reductions in FFAs (r = -0.62, P = 0.003) and lipolysis (r = -0.59, P = 0.005). CONCLUSIONS: Acipimox resulted in significant sustained reductions in lipolysis, improved glucose homeostasis, and significant but modest reductions in triglycerides in HIV-infected individuals with abnormal fat distribution and hypertriglyceridemia. Improvement in overall metabolic profile with acipimox suggests a potential clinical utility for this agent that requires further investigation.

Effects of switching from lopinavir/ritonavir to atazanavir/ritonavir on muscle glucose uptake and visceral fat in HIV-infected patients.

OBJECTIVE: To determine the effects of switching from lopinavir/ritonavir (LPV/r) to atazanavir/ritonavir (ATV/r) on muscle glucose uptake, glucose homeostasis, lipids, and body composition. METHODS: Fifteen HIV-infected men and women on a regimen containing LPV/r and with evidence of hyperinsulinemia and/or dyslipidemia were randomized to continue LPV/r or to switch to ATV/r (ATV 300 mg and ritonavir 100 mg daily) for 6 months. The primary endpoint was change in thigh muscle glucose uptake as measured by positron emission tomography. Secondary endpoints included abdominal visceral adipose tissue, fasting lipids, and safety parameters. The difference over time between treatment groups (treatment effect of ATV/r relative to LPV/r) was determined by repeated measures ANCOVA. RESULTS: After 6 months, anterior thigh muscle glucose uptake increased significantly (treatment effect +18.2 +/- 5.9 micromol/kg per min, ATV/r vs. LPV/r, P = 0.035), and visceral adipose tissue area decreased significantly in individuals who switched to ATV/r (treatment effect -31 +/- 11 cm, ATV/r vs. LPV/r, P = 0.047). Switching to ATV/r significantly decreased triglyceride (treatment effect -182 +/- 64 mg/dl, ATV/r vs. LPV/r, P = 0.02) and total cholesterol (treatment effect -23 +/- 8 mg/dl, ATV/r vs. LPV/r, P = 0.01), whereas high-density lipoprotein and low-density lipoprotein did not change significantly. Fasting glucose also decreased significantly following switch to ATV/r (treatment effect -15 +/- 4 mg/dl, ATV/r vs. LPV/r, P = 0.002). CONCLUSION: Switching from LPV/r to ATV/r significantly increases glucose uptake by muscle, decreases abdominal visceral adipose tissue, improves lipid parameters, and decreases fasting glucose over 6 months.

Decreased respiratory quotient in relation to resting energy expenditure in HIV-infected and noninfected subjects.

The purpose of this study was to evaluate the relationship of respiratory quotient (RQ), a surrogate marker of substrate oxidation, as well as body composition and dietary intake to resting energy expenditure (REE) among HIV-infected patients in the current era of highly active antiretroviral therapy and among non-HIV-infected control subjects. Resting energy expenditure is increased in HIV-infected patients; but little is known regarding the potential contribution of altered substrate metabolism, body composition, and dietary intake to increased energy expenditure in this population. Respiratory quotient, REE, body composition, and dietary intake parameters were assessed in 283 HIV-infected patients and 146 community-derived HIV-negative controls who were evaluated for metabolic studies between 1998 and 2005. Respiratory quotient was lower (0.83 +/- 0.00 vs 0.85 +/- 0.01, P = .005), whereas REE adjusted for fat-free mass (FFM) was higher (31.8 +/- 0.3 vs 29.8 +/- 0.3 kcal/[d kg], P < or = .0001), in HIV-infected compared with control subjects. In multivariate modeling among HIV-infected patients, including age, sex, and parameters of immune function, FFM (beta = 24.811334, P < .0001), visceral adiposity (beta = .7182746, P = .008), and total body fat (beta = 8.0506839, P = .041) were positively associated with REE, whereas RQ was negatively associated with REE (beta = -528.4808, P = .024). Overall r(2) was equal to 0.705 and P was less than .0001 for the model. In control subjects, by contrast, only visceral adiposity (beta = 1.0612073, P = .004), total body fat (beta = 15.805547, P = .010), and FFM (beta = 22.613005, P < .0001) were significant predictors of REE; and there was no relationship with RQ. Overall r(2) was equal to 0.825 and P was less than .0001 for the model. These data suggest that alterations in substrate metabolism may contribute to increased REE in HIV-infected patients compared with control subjects.

Relation of body composition to body mass index in HIV-infected patients with metabolic abnormalities.

OBJECTIVE: To determine visceral adiposity (VAT), subcutaneous adiposity (SAT), and regional body adipose differences between HIV-infected and non-HIV-infected subjects in relation to body mass index (BMI) and World Health Organization BMI categories. DESIGN, SETTING, AND PARTICIPANTS: Analyses were conducted of 306 HIV-infected and 107 community-derived HIV-negative subjects evaluated for metabolic studies between 1999 and 2006. Analyses were stratified by gender. Additional analyses were performed stratifying subjects by metabolic syndrome status. RESULTS: HIV-infected men and women demonstrated decreased total extremity fat by 1.1 kg and 0.85 kg, respectively, relative to non-HIV-infected control subjects. VAT was increased among HIV-infected men and women in the normal (18.5 to 24.9 kg/m2) and overweight (25.0 to 29.9 kg/m2) categories relative to control subjects but not among those in the obese category (> or =30.0 kg/m2). In contrast, abdominal SAT was reduced among HIV-infected men in the normal and overweight categories but was similar among HIV-infected women and control subjects in these categories. Abdominal SAT was increased among HIV-infected women in the obese category relative to control subjects. Similar results were obtained limiting the analysis to HIV-infected (n = 204) and control subjects (n = 89) without the metabolic syndrome. CONCLUSIONS: Peripheral lipoatrophy is a consistent finding among HIV-infected men and women with metabolic abnormalities. Relative increases in VAT are most pronounced among male and female HIV-infected subjects in the normal weight and overweight categories. Gender differences in abdominal SAT accumulation are observed, with preservation of SAT among HIV-infected women relative to control subjects.

Magnetic resonance spectroscopy of hepatic lipid content and associated risk factors in HIV infection.

BACKGROUND: Liver-related illness is increasingly recognized as a source of morbidity in HIV-infected patients. Fatty infiltration of the liver is potentially an important consequence of HIV and treatment with antiretroviral (ARV) therapy. OBJECTIVE: The aim of the present study was to evaluate HIV-infected men and women for hepatic steatosis using noninvasive magnetic resonance spectroscopy (MRS) and to assess the relationship between liver fat content, insulin resistance, and other associated risk factors. METHODS: We examined 33 consecutively recruited HIV-infected adults without specific referral for liver disease. Subjects with alcohol abuse within 3 years or end-stage liver disease were excluded. The primary clinical measures were hepatic fat content measured by MRS, homeostasis model for assessment of insulin resistance (HOMA-IR), and body fat distribution assessed by cross-sectional computed tomography. RESULTS: We identified hepatic steatosis (liver fat content > or =5%) in 42% of subjects. Hepatic fat content was significantly correlated with HOMA-IR (r = 0.68, P < 0.0001) and increased visceral adiposity (r = 0.60, P < 0.001). Subjects with steatosis had significantly increased body mass index and alanine aminotransferase and triglyceride levels, with lower muscle attenuation (ie, increased intramuscular fat) compared to subjects without steatosis. However, steatosis was not related to duration of HIV, ARV exposure, or HCV coinfection. CONCLUSIONS: These data suggest that hepatic steatosis may be very common in HIV, not limited to those with HCV coinfection, and may play an important role in the metabolic profile among HIV-infected men and women.