Hypermetabolism and altered substrate oxidation in HIV-infected patients with lipodystrophy

High resting energy expenditure, less fat-free mass, and less muscle strength in HIV-infected children: a matched, cross-sectional study

Background and aims

Many improvements have been made in the treatment of human immunodeficiency virus (HIV) in pediatric patients; however, challenges remain in terms of achieving normal growth, body composition, and metabolism during treatment, etc. Current nutritional recommendations are based on studies performed in adults, with limited data on the HIV-infected pediatric population. Therefore, this study aimed to compare the resting energy expenditure (REE) of asymptomatic HIV-infected pediatric patients with healthy counterparts and to compare body composition, dietary intake, and physical activity between the two groups.

Methods

This was a cross-sectional study of asymptomatic HIV-infected children who were receiving antiretroviral therapy; the infected group was compared with the uninfected group, matched by age (± 6 months), sex, and body mass index (± 0.5 z-score). Participants were recruited between 2021 and 2022, as outpatients. In both groups, REE was determined by indirect calorimetry and body composition by bioelectrical impedance analysis and hand strength, measured using a hydraulic hand dynamometer.

Results

Seventy-eight participants were enrolled, where n = 39 HIV-infected children and n = 39 controls, with a mean age of 11.6 ± 3.4 years old. REE was significantly higher in the HIV group (1254.4 ± 334.7 kcal/day vs. 1124.7 ± 321 kcal/day, p = 0.013) than in the control group. Fat-free mass (FFM) was lower in the HIV group (28.2 ± 10.5 kg vs. 32 ± 11.2 kg, p = 0.001); this trend continued when the index skeletal muscle was evaluated (7.2 ± 1.2 vs. 7.6 ± 1.5, p = 0.04). The strength of the dominant hand was also lower in the HIV group (12 (8-18) kg vs. 20 (10.5-26) kg, p < 0.0001).

Conclusions

Children with asymptomatic HIV infection have higher REE than their uninfected peers. They also present decreased FFM, skeletal muscle mass index, and muscle strength. These parameters should be considered during nutritional assessment in this population to have a favorable impact on nutritional status and growth.

Effect of Training and Detraining in the Components of Physical Fitness in People Living With HIV/AIDS

The aim of the study was to evaluate the effect of training and detraining on the physical fitness components of people living with HIV/AIDS (PLHA). The study was characterized as experimental with a sample composed of 21 people divided into two groups: 11 volunteers (PLHA, 46.9 ± 8.0 years, 63.8 ± 12.7 kg, 161.7 ± 8.7 cm, 7 men, and 4 women), using antiretroviral therapy (ART) and 10 people without HIV/AIDS in the control group (CG, 43.8 ± 13.8 years, 75.2 ± 11.2 kg, 163.3 ± 7.8 cm, 3 men, and 7 women), with the same average age and level of physical activity. The intervention, applied to both groups, consisted of combined training for 15 weeks, followed by detraining for 5 weeks. Before and after the training and detraining period the following parameters were evaluated: body composition by dual energy radiological absorptiometry (DXA), cardiorespiratory fitness by ergospirometer, and strength of upper and lower limbs by isometric dynamometer. The results show the effect of the intervention moments on the strength and oxygen consumption variables (time factor), considering the two study groups. Regarding the analysis of the interaction (group vs. time), there was a significant effect on the isometric extension strength of the left (p = 0.019) and right (p = 0.030) knees, with training (left: 10.4%; right: 12.4%) and detraining (left: −10.8%; right: −12.1%) effect in PLHA, when compared with the control group (left: 8.1 and 3.9%, respectively; right: 11.5 and −0.2%, respectively). In addition, there was a significant interaction on ventilatory threshold 1 (p = 0.002), indicating a significantly greater increase with training (27.3%) and decrease with detraining (−22.7%) in the PLHA group compared with the Control group (19.9 and −6.7%, respectively). In conclusion, combined training and the subsequent period of detraining caused similar responses in body composition, isometric strength, and cardiorespiratory fitness of PLHA and CG, except for the extensor strength of the lower limbs and ventilatory threshold 1, which presented positive effects on training and negative effects on detraining for PLHA.

Clinical Trial Registration:www.ClinicalTrials.gov, identifier NCT03075332.

Resting energy expenditure in HIV/AIDS patients: Development and validation of a predictive equation

BACKGROUND

Accurate measurements of resting energy expenditure (REE) are important for determining nutritional needs in HIV patients. Indirect calorimetry (IC) is a noninvasive method that reflects REE but can be costly and is frequently calculated with predictive equations. Research suggests that REE obtained by predictive equations in people living with HIV/AIDS (PLWH) is inaccurate. The aim of the study is to develop and validate a new predictive equation of REE based on a population of PLWH.

METHODS

Cross-sectional study including 164 PLWH (82 to develop and 82 to validate the equation). Multiple linear regression was used to determine the relationship between variables and to develop the new predictive equation. Intraclass correlation coefficient (ICC) and Bland-Altman methods were used to evaluate agreement between the new predictive equation and indirect calorimetry.

RESULTS

A new predictive equation with an accuracy of 67% when compared with IC was developed. This equation included as covariates: fat free mass, antiretroviral therapy status and age.

CONCLUSION

A new equation to predict energy expenditure in PLWH was developed and validated. This formula can be used to estimate REE if IC is not available.

Anthropometric cutoff points to identify lipodystrophy characteristics in people living with HIV/AIDS: an observational study

Introduction

Introduction: currently, there is no consensus regarding accurate and low-cost methods for diagnosing lipodystrophy in people living with HIV/AIDS (PLWHA). The aim of this study was to propose anthropometric cutoff points for the diagnosis of lipodystrophy among PLWHA. Methods: we included 106 PLWHA (men = 65, women = 41) who are under antiretroviral therapy and have been clinically classified into either a "lipodystrophy" or "non-lipodystrophy" group. Anthropometric measurements included 19 regions of body perimeters and 6 skinfold thickness measures. The Youden index was used to establish anthropometric cutoff points for the diagnosis of lipodystrophy, using the mean values of the anthropometric data (referred to as "original") along with the "Z index" (ZI) values, which were adjusted by the "Phantom Strategy." The cutoff points were proposed when "original" anthropometric measurements and ZI values had a statistical significance of p < 0.01 and an area under the curve (AUC) higher than 70%. The size effect was assessed to verify the influence of lipodystrophy on each anthropometric measure. Results: our data analysis proposes sex-specific cutoff points for the diagnosis of lipodystrophy in PLWHA - 17 points using the "original" anthropometric measurements, and 20 using the ZI values (average effect size between 1.0 and 1.1, and AUC = 76.7% and 78%). Conclusions: our study proposes accurate cutoff points for the diagnosis of lipodystrophy using "original" anthropometric measurements and ZI values adjusted by the "Phantom Strategy." Our findings support the use of anthropometric measurements as a simplified method for diagnosing lipodystrophy and monitoring body composition alterations in people living with HIV/AIDS.

Practice Paper of the Academy of Nutrition and Dietetics: Nutrition Intervention and Human Immunodeficiency Virus Infection

Nutrition is an integral component of medical care for people living with human immunodeficiency virus (HIV)/autoimmune deficiency syndrome (AIDS) (PLWHA). The Academy of Nutrition and Dietetics supports integration of medical nutrition therapy into routine care for this population. Fewer PLWHA experience wasting and undernutrition, while the prevalence of obesity and other chronic diseases has increased significantly. Improved understanding of HIV infection's impact on metabolism and chronic inflammation has only increased the complexity of managing chronic HIV infection. Nutrition assessment should encompass food insecurity risk, changes in body composition, biochemical indices, and clinical indicators of comorbid disease. Side effects from current antiretroviral therapy regimens are less prevalent than with previous generations of therapy. However, micronutrient deficiencies and chronic anemia also remain significant nutritional risks for PLWHA, making vitamin and mineral supplementation necessary in cases of acute deficiency or food insecurity. Additional factors can impact HIV-related nutrition care among the pediatric population, older adults, minority groups, those co-infected with tuberculosis or hepatitis, and PLWHA in rural or underserved areas. Registered dietitian nutritionists and nutrition and dietetic technicians, registered should participate in multidisciplinary care to incorporate nutrition into the medical management of PLWHA.

Influence of curcumin supplementation on metabolic and lipid parameters of people living with HIV/AIDS: a randomized controlled trial

Background

Scientific studies have shown that the potential therapeutic efficacy of curcumin in several diseases is due to its potent antioxidant and anti-inflammatory properties. Consequently, curcumin supplementation seems to be a valuable alternative for HIV-infected individuals. The aim of this study is to evaluate the influence of curcumin supplementation on substrate oxidation at rest, body composition, and the lipid profile of physically active people living with HIV/AIDS under antiretroviral therapy.

Methods

This double-blind, crossover, randomized clinical trial was comprised of 20 subjects divided into experimental (EG) and control (CG) groups, receiving 1000 mg curcumin/day and placebo, respectively, during a 30-day period. Substrate oxidation at rest was assessed by indirect calorimetry, body composition was measured by dual-energy x-ray absorptiometry, and the lipid profile was evaluated by blood tests. Data analysis was performed by independent samples and paired t-tests to compare the differences between groups and times. A p-value < 0.05 was accepted as significant.

Results

There were no differences between groups regarding substrate oxidation at rest or body composition. However, serum triglyceride levels were increased after curcumin supplementation (182 vs. 219 mg/dL; p = 0.004).

Conclusion

Curcumin supplementation promoted the elevation of serum triglyceride levels in HIV-infected subjects. Further studies with a larger sample cohort, different curcumin doses, and longer intervention times are needed to validate current observations. In addition, the influence of physical activity, dietary intake, and genetic polymorphisms must be considered in future studies to better understand the impact of curcumin supplementation on the lipid profile of people living with HIV/AIDS under antiretroviral therapy.

Electronic supplementary material

The online version of this article (10.1186/s12906-019-2620-7) contains supplementary material, which is available to authorized users.

Physiological responses to leptin levels in lipodystrophy: a model for other hypoleptinemias?

Brown et al. report that two weeks of exogenous leptin administration to leptin-naive individuals with lipodystrophy resulted in increased energy expenditure and lipolysis, decreased ectopic liver fat, improved hepatic and peripheral insulin sensitivity, and attenuated dyslipidemia. Leptin withdrawal in individuals with lipodystrophy did not produce reciprocal effects on these phenotypes and resulted in significant improvements only in hepatic insulin sensitivity. This asymmetry in responses to leptin initiation and cessation is consistent with the other aspects of leptin biology that are dependent on the metabolic context in which this adipocyte-derived hormone functions.

Low expression of IL-18 and IL-18 receptor in human skeletal muscle is associated with systemic and intramuscular lipid metabolism-Role of HIV lipodystrophy

Introduction

Interleukin (IL)-18 is involved in regulation of lipid and glucose metabolism. Mice lacking whole-body IL-18 signalling are prone to develop weight gain and insulin resistance, a phenotype which is associated with impaired fat oxidation and ectopic skeletal muscle lipid deposition. IL-18 mRNA is expressed in human skeletal muscle but a role for IL-18 in muscle has not been identified. Patients with HIV-infection and lipodystrophy (LD) are characterized by lipid and glucose disturbances and increased levels of circulating IL-18. We hypothesized that skeletal muscle IL-18 and IL-18 receptor (R) expression would be altered in patients with HIV-lipodystrophy.

Design and methods

Twenty-three HIV-infected patients with LD and 15 age-matched healthy controls were included in a cross-sectional study. Biopsies from the vastus lateralis muscle were obtained and IL-18 and IL-18R mRNA expression were measured by real-time PCR and sphingolipids (ceramides, sphingosine, sphingosine-1-Phosphate, sphinganine) were measured by HPLC. Insulin resistance was assessed by HOMA and the insulin response during an OGTT.

Results

Patients with HIV-LD had a 60% and 54% lower level of muscular IL-18 and IL-18R mRNA expression, respectively, compared to age-matched healthy controls. Patients with HIV-LD had a trend towards increased levels of ceramide (18.3±4.7 versus 14.8±3.0,p = 0.06) and sphingosine (0.41±0.13 versus 0.32±0.07, and lower level of sphinganine (p = 0.06). Low levels of muscle IL-18 mRNA correlated to high levels of ceramides (r = -0.31, p = 0.038) and sphingosine-1P (r = -0.29, p = 0.046) in skeletal muscle, whereas such a correlation was not found in healthy controls. Low expression of IL-18 mRNA in skeletal muscle correlated to elevated concentration of circulating triglycerides (R_p = -0.73, p<0.0001). Neither muscle expression of IL-18 mRNA or ceramide correlated to parameters of insulin resistance.

Conclusion

IL-18 (mRNA) in skeletal muscle appears to be involved in the regulation of intramuscular lipid metabolism and hypertriglyceridemia.

Accuracy of Predictive Equations for Energy Expenditure in Mexicans Living With HIV/AIDS With and Without Antiretroviral Therapy

INTRODUCTION

Determination of the resting energy expenditure (REE) is essential for planning nutrition therapy in patients with human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) to help to improve their nutrition status. We aim to evaluate the agreement and accuracy of prediction equations that estimate the REE in a Mexican population with a diagnosis of HIV/AIDS with and without antiretroviral therapy (ART).

METHODS

A cross-sectional study in Mexican patients with HIV/AIDS with and without ART. Weight, height, and body composition measured with dual-energy x-ray absorptiometry were evaluated. The REE was determined with indirect calorimetry and estimated using the Mifflin-St Jeor (MSJ), Harris-Benedict (HB), Schofield 1 and 2, Cunningham, Melchior 91, Melchior 93, and Batterham equations. The Bland-Altman method assessed agreement between the real and estimated values, and the percent difference between these values was used to assess the prediction accuracy.

RESULTS

Sixty-five adults without ART and 102 adults with ART were included. The mean REE (kcal/kg) was 24.8 ± 2.4 and 23.8 ± 3.6 in patients without and with ART, respectively. Good agreement and reliability were observed in the HB (intraclass correlation coefficient [ICC], 0.75; P < .05), Batterham (ICC, 0.79; P < .05), Schofield 1 (ICC, 0.74; P < .05), and Schofield 2 (ICC, 0.78; P < .05) results in individuals without ART. In individuals with ART, good agreement and reliability were observed with the HB equation (ICC, 0.76; P < .05). The MSJ equation showed good agreement with poor reliability (ICC, 0.05; P < .05).

CONCLUSION

The equations with the best agreement and accuracy were Schofield 2, Batterham, and HB in individuals without ART and HB and MSJ in the population with ART.

Doubly Labeled Water Method and Accelerometer for the Measurement of Energy Expenditure in Human Immunodeficiency Virus-Infected Patients

BACKGROUND

Several studies have reported increased resting energy expenditure (REE) in human immunodeficiency virus (HIV)-infected patients with HIV-associated lipodystrophy syndrome (HALS). However, limited data exist on the total energy expenditure (TEE). This study was aimed at evaluating the REE and TEE of HIV-infected patients with and without HALS by using the doubly labeled water (DLW) technique and the activity monitor based on accelerometry system (AM), and comparing the results obtained using both methods.

METHODS

Evaluated total of 45 HIV+ men undergoing antiretroviral therapy, including 18 LIPO- (without lipodystrophy) and 27 LIPO+ (with lipodystrophy) individuals were evaluated. Habitual physical activity patterns were measured by using the ActivPAL™ AM system, REE by indirect calorimetry, and TEE by DLW and AM.

RESULTS

No significant differences were found between LIPO- and LIPO+ in REE (1,433 ± 196 vs. 1,510 ± 203 kcal), TEE-DLW (2,691 ± 856 vs. 2,618 ± 415 kcal) and TEE-AM (2,560 ± 458 vs. 2,594 ± 456 kcal), respectively. RQ was a predictor of REE in LIPO+. TEE estimated by the AM had a moderate correlation with DLW, but there was a wide variance in the intra-subject results.

CONCLUSIONS

TEE is not increased in HIV-infected patients with HALS. AM should be used with caution for TEE evaluation during clinical practice.

HIV/AIDS and lipodystrophy: implications for clinical management in resource-limited settings

Introduction

Lipodystrophy is a term used to describe a metabolic complication of fat loss, fat gain, or a combination of fat loss and gain, which is associated with some antiretroviral (ARV) therapies given to HIV-infected individuals. There is limited research on lipodystrophy in low- and middle-income countries, despite accounting for more than 95% of the burden of HIV/AIDS. The objective of this review was to evaluate the prevalence, pathogenesis and prognosis of HIV-related lipoatrophy, lipohypertrophy and mixed syndrome, to inform clinical management in resource-limited settings.

Methods

We conducted a structured literature search using MEDLINE electronic databases. Relevant MeSH terms were used to identify published human studies on HIV and lipoatrophy, lipohypertrophy, or mixed syndrome in low-, low-middle- and upper-middle-income countries through 31 March 2014. The search resulted in 5296 articles; after 1599 studies were excluded (958 reviews, 641 non-human), 3697 studies were extracted for further review. After excluding studies conducted in high-income settings (n=2808), and studies that did not meet inclusion criteria (n=799), 90 studies were included in this review.

Results and Discussion

Of the 90 studies included in this review, only six were from low-income countries and eight were from lower middle-income economies. These studies focused on lipodystrophy prevalence, risk factors and side effects of antiretroviral therapy (ART). In most studies, lipodystrophy developed after the first six months of therapy, particularly with the use of stavudine. Lipodystrophy is associated with increased risk of cardiometabolic complications. This is disconcerting and anticipated to increase, given the rapid scale-up of ART worldwide, the increasing number and lifespan of HIV-infected patients on long-term therapy, and the emergence of obesity and non-communicable diseases in settings with extensive HIV burden.

Conclusions

Lipodystrophy is common in resource-limited settings, and has considerable implications for risk of metabolic diseases, quality of life and adherence. Comprehensive evidence-based interventions are urgently needed to reduce the burden of HIV and lipodystrophy, and inform clinical management in resource-limited settings.

Effect of increasing glutathione with cysteine and glycine supplementation on mitochondrial fuel oxidation, insulin sensitivity, and body composition in older HIV-infected patients

BACKGROUND

HIV-infected patients are reported to have impaired oxidation of fatty acids despite increased availability, suggesting a mitochondrial defect. We investigated whether diminished levels of a key mitochondrial antioxidant, glutathione (GSH), was contributing to defective fatty acid oxidation in older HIV-infected patients, and if so, the metabolic mechanisms contributing to GSH deficiency in these patients.

METHODS

In an open-label design, 8 older GSH-deficient HIV-infected males were studied before and after 14 days of oral supplementation with the GSH precursors cysteine and glycine. A combination of stable-isotope tracers, calorimetry, hyperinsulinemic-euglycemic clamp, and dynamometry were used to measure GSH synthesis, fasted and insulin-stimulated (fed) mitochondrial fuel oxidation, insulin sensitivity, body composition, anthropometry, forearm-muscle strength, and lipid profiles.

RESULTS

Impaired synthesis contributed to GSH deficiency in the patients and was restored with cysteine plus glycine supplementation. GSH improvement was accompanied by marked improvements in fasted and fed mitochondrial fuel oxidation. Associated benefits included improvements in insulin sensitivity, body composition, anthropometry, muscle strength, and dyslipidemia.

CONCLUSIONS

This work identifies 2 novel findings in older HIV-infected patients: 1) diminished synthesis due to decreased availability of cysteine and glycine contributes to GSH deficiency and can be rapidly corrected by dietary supplementation of these precursors and 2) correction of GSH deficiency is associated with improvement of mitochondrial fat and carbohydrate oxidation in both fasted and fed states and with improvements in insulin sensitivity, body composition, and muscle strength. The role of GSH on ameliorating metabolic complications in older HIV-infected patients warrants further investigation.

Analyzing weight loss intervention studies with missing data: which methods should be used?

OBJECTIVE

Missing data due to study dropout is common in weight loss trials and several statistical methods exist to account for it. The aim of this study was to identify methods in the literature and to compare the effects of methods of analysis using simulated data sets.

METHODS

Literature was obtained for a 1-y period to identify analytical methods used in reporting weight loss trials. A comparison of methods with large or small between-group weight loss, and missing data that was, or was not, missing randomly was conducted in simulated data sets based on previous research.

RESULTS

Twenty-seven studies, some with multiple analyses, were retrieved. Complete case analysis (n = 17), last observation carried forward (n = 6), baseline carried forward (n = 4), maximum likelihood (n = 6), and multiple imputation (n = 2) were the common methods of accounting for missing data. When comparing methods on simulated data, all demonstrated a significant effect when the between-group weight loss was large (P < 0.001, interaction term) regardless of whether the data was missing completely at random. When the weight loss interaction was small, the method used for analysis gave considerably different results with mixed models (P = 0.180) and multiple imputations (P = 0.125) closest to the full data model (P = 0.033).

CONCLUSION

The simulation analysis showed that when data were not missing at random, treatment effects were small, and the amount of missing data was substantial, the analysis method had an effect on the significance of the outcome. Careful attention must be paid when analyzing or appraising studies with missing data and small effects to ensure appropriate conclusions are drawn.

Which equation should be used to measure energy expenditure in HIV-infected patients?

OBJECTIVE: In view of the practical need to use equations for the evaluation of energy expenditure in HIV-infected patients, the objective of the present study was to determine the concordance between the energy expenditure values obtained by indirect calorimetry as the gold standard and those obtained by predictive equations elaborated from data for the healthy population: Harris-Benedict, Schofield and Cunningham, and by equations elaborated from data for HIV-infected patients: Melchior (1991-1993). METHODS: The study was conducted at the Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto on 32 HIV-infected men under treatment with highly active antiretroviral therapy. Resting energy expenditure was measured by indirect calorimetry and estimated on the basis of measurement of O2 consumption and CO2 production. RESULTS: Statistical analysis revealed weak concordance for the Harris-Benedict (0.38) and Cunningham (0.34) equations and satisfactory concordance for the Schofield equation (0.47). Only the two Melchior equations (1991 and 1993) showed strong concordance with the values obtained by indirect calorimetry (0.63 and 0.66, respectively) and could be used in practice. CONCLUSION: The best equations seem to be population-specific, such as the Melchior equations elaborated for HIV-infected patients.