Changes in abdominal fat following antiretroviral therapy initiation in HIV-infected individuals correlate with waist circumference and self-reported changes

Weight Gain and Antiretroviral Therapy

Antiretroviral therapy (ART) agents as a determinant of body weight in ART-naïve and ART-experienced persons with human immunodeficiency virus (HIV) (PWH) has become a major focus area in research and clinical settings. Recent studies demonstrating weight-suppressing properties of efavirenz and tenofovir disoproxil fumarate led to re-evaluation of weight gain studies, and a reassessment of whether other agents are weight promoting versus weight neutral. In this review, the authors synthesize recent literature on factors related to obesity, clinical measurements of adiposity, weight gain in ART-naïve and ART-experienced PWH, metabolic consequences of ART and weight gain, and the clinical management of weight gain in PWH.

Weight Gain in People with HIV: The Role of Demographics, Antiretroviral Therapy, and Lifestyle Factors on Weight

We explored factors associated with weight gain among people with HIV (PWH) on antiretroviral therapy (ART) at The Ohio State University Wexner Medical Center (OSUWMC). This was a retrospective cohort study of adult PWH on ART for ≥3 months. Patients with CD4+ T cell count <200 cells/mm3, viral load >200 copies/mL, history of malignancy, or pregnancy were excluded. Eight hundred seventy patients met criteria. The primary outcome was percent weight change over the follow-up period (Δ = relative effects). The secondary outcome was the odds of ≥5 kg weight gain over the study period. The effects of concurrent medications, medical comorbidities, ART combinations, and lifestyle behaviors on these outcomes were modeled using mixed effects regression analyses. Over a mean follow-up of 1.86 years, the study population gained a mean percent weight of 2.12% ± 0.21% (p < .001) with the odds of ≥5 kg weight gain of 0.293 (p < .001). Males gained an average of 1.88% ± 0.22% over follow up, while females gained an average of 3.37% ± 0.51% over follow up (p = .008 for the difference). In regression models, combination therapy with tenofovir alafenamide (TAF) and integrase strand transfer inhibitor (INSTI) containing regimens was associated with an increase in weight over the study period (Δ = 2.14% ± 0.45%, p < .001 and Δ = 1.09% ± 0.39%, p = .005, respectively). Increasing age was significantly associated with a decrease in percent weight change over the study period (Δ = -0.68% ± 0.18% per year, p < .001). Self-reported improvement in diet was associated with a decrease in weight change (Δ = -1.99% ± 0.47%, p ≤ .001) and reduced odds of ≥5 kg weight gain (odds ratio = 0.70, 95% confidence interval = 0.50-0.97, p = .03). Factors associated with weight gain include therapy with TAF and INSTI. Diet may play an influential role in attenuating weight gain in PWH.

Adipocyte differentiation of 3T3-L1 cells under tenofovir alafenamide, tenofovir disoproxil fumarate, and integrase strand transfer inhibitors selective challenge: an in-vitro model

OBJECTIVE

Integrase strand transfer inhibitors (INSTIs) are a class of antiretroviral therapy (ART) medications with a good tolerability profile and a high genetic barrier to HIV drug resistance. However, several studies report significant weight gain among persons receiving INSTI-based ART regimens compared with other regimens.

DESIGN

In-vitro model of adipogenesis.

METHODS

We used 3T3-L1 cells to investigate the effects of the nucleoside reverse transcriptase inhibitors (NRTIs) tenofovir disoproxil fumarate (TDF) and tenofovir alafenamide (TAF), alone or in combination with INSTIs: raltegravir (RAL), elvitegravir (ELV), dolutegravir (DTG), and bictegravir (BIC) on adipose differentiation. To monitor adipocyte differentiation, expression levels of PPARɣ and C/EBPα and the intracellular lipid accumulation by Red Oil staining were used. Furthermore, we evaluated the immunohistochemical expression of ER-TR7, a fibroblastic marker, after INSTIs treatment.

RESULTS

Compared with control, INSTIs were able to increase adipogenesis, especially RAL and ELV. TAF and TDF inhibited adipogenesis alone and in combination with INSTIs. This ability was more evident when TAF was used in combination with DTG and BIC. Finally, INSTIs increased the expression of ER-TR7 compared with control and cells treated with TAF or TDF.

CONCLUSION

Our data support the evidence that in-vitro challenge of 3T3-L1 cells with INSTIs is able to increase adipocytic differentiation and to drive a number of these cells toward the expression of fibroblastic features, with a different degree according to the various drugs used whereas TAF and TDF have an antagonistic role on this phenomenon.

Effects of Two Different Exercise Training Programs Periodization on Anthropometric and Functional Parameters in People Living with HIV: A Randomized Clinical Trial

The purpose of this study was to investigate the effects of two different exercise training programs periodization on anthropometric and functional parameters in people living with HIV (PLHIV). This was a randomized clinical trial that involved participants (n = 31) living with HIV aged over 18 years and undergoing antiretroviral therapy which were randomized to periodized exercise training (PET; n = 13), non-periodized exercise training (NPET; n = 13), or control group (CON; n = 15). The PET and NPET groups performed 12 weeks of combined training while the CON group maintained the usual activities. Before and after 12 weeks of intervention were measured body composition and perimeters, muscle strength, Short Physical Performance Battery (SPPB) and Timed Up and Go (TUG) test time.

RESULTS

The PET and NPET groups increased fat-free mass (p < 0,001), right (p < 0,001) and left thigh perimeter (p < 0,001), muscle strength (p < 0,001), handgrip force (p < 0,001), and reduced the fat mass (p < 0,001), neck perimeter (p < 0,001), chair stand (p < 0,001), and time-up and go test time (p < 0,001) compared to CON. Furthermore, PET was significantly different to increase right thigh and muscle strength (p < 0,05) compared to NPET.

CONCLUSION

Both exercise training periodization protocols were effective to improve body composition and functional outcomes; however, seems that PET presents better results compare to NPET in PLHIV.

Chronic binge alcohol and ovariectomy-mediated impaired insulin responsiveness in SIV-infected female rhesus macaques

Aging people living with HIV (PLWH), especially postmenopausal women may be at higher risk of comorbidities associated with HIV, antiretroviral therapy (ART), hypogonadism, and at-risk alcohol use. Our studies in simian immunodeficiency virus (SIV)-infected male macaques demonstrated that chronic binge alcohol (CBA) reduced acute insulin response to glucose (AIRG), and at-risk alcohol use decreased HOMA-β in PLWH. The objective of this study was to examine the impact of ovariectomy (OVX) on glucose-insulin dynamics and integrity of pancreatic endocrine function in CBA/SIV-infected female macaques. Female macaques were administered CBA (12-15 g/kg/wk) or isovolumetric water (VEH) intragastrically. Three months after initiation of CBA/VEH administration, all macaques were infected with SIVmac251, and initiated on antiretroviral therapy (ART) 2.5 mo postinfection. After 1 mo of ART, macaques were randomized to OVX or sham surgeries (n = 7 or 8/group), and euthanized 8 mo post-OVX (study endpoint). Frequently sampled intravenous glucose tolerance tests (FSIVGTT) were performed at selected time points. Pancreatic gene expression and islet morphology were determined at study endpoint. There was a main effect of CBA to decrease AIRG at Pre-SIV and study endpoint. There were no statistically significant OVX effects on AIRG (P = 0.06). CBA and OVX decreased the expression of pancreatic markers of insulin docking and release. OVX increased endoplasmic stress markers. CBA but not OVX impaired glucose-insulin expression dynamics in SIV-infected female macaques. Both CBA and OVX altered integrity of pancreatic endocrine function. These findings suggest increased vulnerability of PLWH to overt metabolic dysfunction that may be exacerbated by alcohol use and ovarian hormone loss.

Metabolic Changes in Pediatric HIV-Positive Patients and Potential Lifestyle Interventional Strategies

Metabolic changes in the HIV population have been well-studied, particularly after the advent of antiretroviral therapy. More notably, the emergence of the metabolic syndrome within the HIV population, due to prolonged survival, has led to an increasing rate of cardiovascular occurrence and mortality within the population in adult life. Importance of early intervention in HIV children, particularly lifestyle modifications, is necessary to reduce cardiovascular disease (CVD) risk and mortality in adulthood. Potential clinical interventions include routine anthropometric measurements as a measure of CVD risk, a low saturated fat and high fiber diet, and vigorous aerobic exercise have been shown to decrease CVD risk in the HIV population. The literature review found multiple knowledge gaps due to minimal studies completed on the HIV population and even less on HIV-positive children. Overall, a standardized protocol was required to better care for HIV-positive children and potential future CVD mortality.

Metabolic syndrome in Zambian adults with human immunodeficiency virus on antiretroviral therapy: Prevalence and associated factors

Metabolic syndrome (MetS) is a constellation of factors including hypertension, abdominal obesity, dyslipidemia, and insulin resistance that separately and together significantly increase risk for cardiovascular disease (CVD) and diabetes. In sub-Saharan Africa, with a substantial burden of human immunodeficiency virus (HIV) and increasing prevalence of CVD and diabetes, there is a paucity of epidemiological data on demographic, laboratory, and clinical characteristics associated with MetS among people with HIV (people with human [PWH]). Therefore, this study aimed to determine the burden and factors influencing MetS in antiretroviral therapy (ART)-experienced individuals in Zambia.We collected cross-sectional demographic, lifestyle, anthropometric, clinical, and laboratory data in a cohort of ART-experienced (on ART for ≥6 months) adults in 24 urban HIV treatment clinics of Zambia between August, 2016 and May, 2020. MetS was defined as having ≥3 of the following characteristics: low high density lipoprotein cholesterol (HDL-c) (<1.0 mmol/L for men, <1.3 for women), elevated waist circumference (≥94 cm for men, ≥80 cm for women), elevated triglycerides (≥1.7 mmol/L), elevated fasting blood glucose (≥5.6 mmol/L), and elevated blood pressure (BP) (systolic BP ≥130 or diastolic BP ≥85 mm Hg). Virological failure (VF) was defined as HIV viral load ≥1000 copies/mL. The following statistical methods were used: Chi-square test, Wilcoxon rank-sum test, and multivariable logistic regression.Among 1108 participants, the median age (interquartile range [IQR]) was 41 years (34, 49); 666 (60.1%) were females. The prevalence of MetS was 26.3% (95% confidence interval [CI] 23.9-29.1). Age (adjusted odds ratio [OR] 1.07; 95% CI 1.04-1.11), female sex (OR 3.02; 95% CI 1.55-5.91), VF (OR 1.98; 95% CI 1.01-3.87), dolutegravir (DTG)-based regimen (OR 2.10; 95% CI 1.05-4.20), hip-circumference (OR 1.03; 95% CI 1.01-1.05), T-lymphocyte count (OR 2.23; 95% CI 1.44-3.43), high-sensitivity C-reactive protein (hsCRP) (OR 1.14; 95% CI 1.01-1.29), and fasting insulin (OR 1.02; 95% CI 1.01-1.04) were significantly associated with MetS.Metabolic syndrome was highly prevalent among HIV+ adults receiving ART in Zambia and associated with demographic, clinical, anthropometric, and inflammatory characteristics. The association between MetS and dolutegravir requires further investigation, as does elucidation of the impact of MetS on ART outcomes in sub-Saharan African PWH.

Fat Mass Ratio in Brazilian HIV-infected Patients Under Antiretroviral Therapy and Its Relationship With Anthropometric Measurents

INTRODUCTION

Human immunodeficiency virus-related lipodystrophy is characterized by a variety of phenotypes and metabolic changes; however, consensus has not yet been reached on its diagnostic criteria. Different cutoff values for fat mass ratio have been proposed for this specific population as an objective diagnostic criterion for lipodystrophy. This study aimed to establish sex-specific reference values for fat mass ratio and to correlate them with anthropometric measurements for the diagnosis of human immunodeficiency virus-related lipodystrophy.

METHODOLOGY

A cross-sectional study was performed on 189 human immunodeficiency virus-infected patients under antiretroviral therapy. Anthropometric measurements were evaluated, and body composition was determined using dual-energy X-ray absorptiometry. Fat mass ratio was calculated as the ratio of the percentage of the trunk fat mass and the percentage of the lower limb fat mass.

RESULTS

One hundred and thirty-two patients (69%) presented lipodystrophy by objective criteria. In men, the cutoff for the fat mass ratio was 1.55 (area under the receiver operating characteristic curve: 0.73 [95% confidence interval: 0.62-0.83], p = 0.000008), with a sensitivity of 62.5%, a specificity of 70.5%, a positive predictive value of 77.8%, and a negative predictive value of 53.4%. In women, the cutoff for the fat mass ratio was 0.959 (area under the receiver operating characteristic curve: 0.70 [95% confidence interval: 0.56-0.85], p = 0.03), with a sensitivity of 83.60%, a specificity of 61.5%, a positive predictive value of 90.2%, and a negative predictive value of 47.1%. Fat mass ratio was positively correlated with waist circumference (men: r = 0.246, p = 0.019; women: r = 0.302, p = 0.014) and neck circumference (men: r = 0.304, p = 0.004; women: r = 0.366, p = 0.003) in both sexes; and body mass index (r = 0.288, p = 0.006) and waist-hip ratio (r = 0.288, p = 0.006) in men.

CONCLUSION

The fat mass ratio evaluated using dual-energy X-ray absorptiometry with the sex-specific cutoffs is an objective tool to define human immunodeficiency virus-related lipodystrophy.

Obesity and Fat Metabolism in Human Immunodeficiency Virus-Infected Individuals: Immunopathogenic Mechanisms and Clinical Implications

Metabolic complications relating to complex effects of viral and immune-mediated mechanisms are now a focus of clinical care among persons living with human immunodeficiency virus (PLHIV), and obesity is emerging as a critical problem. To address knowledge gaps, the US National Institutes of Health sponsored a symposium in May 2018 entitled "Obesity and Fat Metabolism in HIV-infected Individuals." Mechanisms relating to adipose dysfunction and fibrosis, immune function, inflammation, and gastrointestinal integrity were highlighted as contributors to obesity among PLHIV. Fibrotic subcutaneous adipose tissue is metabolically dysfunctional and loses its capacity to expand, leading to fat redistribution, including visceral obesity and ectopic fat accumulation, promoting insulin resistance. Viral proteins, including viral protein R and negative regulatory factor, have effects on adipogenic pathways and cellular metabolism in resident macrophages and T cells. HIV also affects immune cell trafficking into the adipose compartments, with effects on adipogenesis, lipolysis, and ectopic fat accumulation. Key cellular metabolic functions are likely to be affected in PLHIV by gut-derived cytokines and altered microbiota. There are limited strategies to reduce obesity specifically in PLHIV. Enhancing our understanding of critical pathogenic mechanisms will enable the development of novel therapeutics that may normalize adipose tissue function and distribution, reduce inflammation, and improve insulin sensitivity in PLHIV.

Changes in Waist Circumference in HIV-Infected Individuals Initiating a Raltegravir or Protease Inhibitor Regimen: Effects of Sex and Race

Background

This study investigates the association of clinical and demographic predictors with abdominal fat gain, measured using waist circumference (WC) and self-reported abdominal size.

Methods

We analyzed data from ACTG A5257, a clinical trial that randomized treatment-naïve HIV-infected participants to 1 of 3 antiretroviral regimens: raltegravir (RAL) or the protease inhibitors (PIs) atazanavir/ritonavir (ATV/r) or darunavir/ritonavir (DRV/r), each in combination with tenofovir disoproxil fumarate/emtricitabine. Associations of treatment and baseline/demographic characteristics with 96-week WC change were assessed using repeated-measures models. Ordinal logistic regression was used to examine the associations of predictors with week 96 self-reported abdominal changes.

Results

The study population (n = 1809) was 76.0% male and predominantly black non-Hispanic (41.9%) and white non-Hispanic (34.1%). Mean baseline WC was 90.6 cm, with an average 96-week increase of 3.4 cm. WC increases were higher in the RAL arm compared with DRV/r (P = .0130). Females experienced greater increases in WC on RAL vs ATV/r than males (P = .0065). Similarly, a larger difference in WC change was found for RAL vs DRV/r for black vs nonblack individuals (P = .0043). A separate multivariable model found that in addition to the treatment regimen, higher baseline viral load and lower CD4+ were also associated with WC increases.

Conclusions

With antiretroviral therapy initiation, higher WC increases in the RAL arm compared with PIs were more pronounced in female and black participants, and a more advanced baseline HIV disease state was a strong predictor of larger abdominal increases. Understanding factors predisposing individuals to abdominal fat gain could inform health management after therapy initiation.

Abdominal obesity, sarcopenia, and osteoporosis are associated with frailty in men living with and without HIV

OBJECTIVE

The relationships between frailty and body composition in older adults with HIV infection are poorly understood. We sought to describe associations between frailty and measures of body composition among adult men with HIV and without HIV.

DESIGN/METHODS

Men with and without HIV (age 50-69 years) in the Multicenter AIDS Cohort Study (MACS) Bone Strength Substudy were included if evaluated for frailty (by Fried phenotype) and body composition [BMI, waist circumference, abdominal visceral (VAT) and subcutaneous (SAT) adipose tissue, sarcopenia, and osteopenia/osteoporosis]. All participants with HIV infection were on antiretroviral therapy. Multivariate multinomial logistic regression models were used to determine associations of frailty with body composition.

RESULTS

A total of 399 men, including 199 men with HIV and 200 men without HIV, both with median age 60 years, constituted our study population. Frailty prevalence was 16% (men with HIV) vs. 8% (men without HIV). HIV serostatus was associated with a 2.43 times higher odds of frailty (P = 0.01). Higher waist circumference, VAT, sarcopenia, and femoral neck osteoporosis were associated with increased odds of frailty (aOR 4.18, 4.45, 4.15, and 13.6, respectively, and all P < 0.05); BMI and SAT were not. None of these measures presented a differential association with frailty by HIV serostatus (all P > 0.20).

CONCLUSION

Higher abdominal obesity and sarcopenia were associated with frailty among men with and without HIV. Assessment of these body composition parameters may help detect frailty in the clinical setting.

The Fat of the Matter: Obesity and Visceral Adiposity in Treated HIV Infection

PURPOSE OF REVIEW

The aim of this review is to summarize knowledge of the prevalence, relevant physiology, and consequences of obesity and visceral adiposity in HIV-infected adults, including highlighting gaps in current knowledge and future research directions.

RECENT FINDINGS

Similar to the general population, obesity prevalence is increasing among HIV-infected persons, and obesity and visceral adiposity are associated with numerous metabolic and inflammatory sequelae. However, HIV- and antiretroviral therapy (ART)-specific factors may contribute to fat gain and fat quality in treated HIV infection, particularly to the development of visceral adiposity, and sex differences may exist. Obesity and visceral adiposity commonly occur in HIV-infected persons and have significant implications for morbidity and mortality. Future research should aim to better elucidate the HIV- and ART-specific contributors to obesity and visceral adiposity in treated HIV infection, with the goal of developing targeted therapies for the prevention and treatment of obesity and visceral adiposity in the modern ART era.

Insulin Resistance in HIV-Patients: Causes and Consequences

Here we review how immune activation and insulin resistance contribute to the metabolic alterations observed in HIV-infected patients, and how these alterations increase the risk of developing CVD. The introduction and evolution of antiretroviral drugs over the past 25 years has completely changed the clinical prognosis of HIV-infected patients. The deaths of these individuals are now related to atherosclerotic CVDs, rather than from the viral infection itself. However, HIV infection, cART, and intestinal microbiota are associated with immune activation and insulin resistance, which can lead to the development of a variety of diseases and disorders, especially with regards to CVDs. The increase in LPS and proinflammatory cytokines circulating levels and intracellular mechanisms activate serine kinases, resulting in insulin receptor substrate-1 (IRS-1) serine phosphorylation and consequently a down regulation in insulin signaling. While lifestyle modifications and pharmaceutical interventions can be employed to treat these altered metabolic functions, the mechanisms involved in the development of these chronic complications remain largely unresolved. The elucidation and understanding of these mechanisms will give rise to new classes of drugs that will further improve the quality of life of HIV-infected patients, over the age of 50.