Methods of assessing body shape and composition in HIV-associated lipodystrophy

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.

Development of predictive equations for total and segmental body fat in HIV-seropositive patients

OBJECTIVES

The central point of the HIV lipodystrophy syndrome is changes in body composition that mainly involve the loss of fat in the limbs and face (lipoatrophy) and/or fat gain in the abdominal region and back neck (lipohypertrophy). Currently, the determination of fat per body segment in this group can be obtained by imaging methods such as dual-energy X-ray absorptiometry (DXA) but not by methods that would be more feasible in the practical clinics. The aim of this study was to develop equations to estimate total body fat and fat in each segment using anthropometric and bioelectrical impedance analysis (BIA) variables in HIV-seropositive patients.

METHODS

We measured circumferences (arm, waist, hip, thigh, calf), skinfolds (biceps, triceps, subscapular, suprailiac) and conducted examinations of BIA, segmental BIA, and DXA in 100 HIV-seropositive men on highly active antiretroviral therapy. Equations were developed by linear regression from these variables to estimate total and segmental fat (arm, leg, and trunk).

RESULTS

We developed a model for estimation of total body fat with BIA variables and a model based on anthropometric variables. To estimate segmental fat, we developed one model for each segment using anthropometric variables. The coefficients of determination for models of total fat-free mass (BIA and anthopometry), arm fat, trunk fat, and leg fat were 0.87, 0.84, 0.66, 0.76, and 0.5, respectively.

CONCLUSIONS

The equations proposed in this study allow the assessment of total body fat and fat per body segment with data obtained from accessible, accurate, and reliable methods used in clinical practice.

Somatometric measurements, and clinical chemistry and hematology parameters in Tibetan macaque (Macaca thibetana)

BACKGROUND

Limited physiological data for Tibetan macaques are available at present. This study will provide more rationale for evaluating this species.

METHODS

Thirty-seven Tibetan macaques (15 males and 22 females) were used in this study. Somatometric measurements, clinical chemistry and hematology parameters, insulin, and C-peptide were analyzed.

RESULTS

Females had higher values of waist and waist hip ratio (WHR) than males in somatometric measurements. There were no significant differences between the two genders in hematology. Significant differences between males and females were only found for aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in biochemistry testing. In addition, females had higher fasting insulin and C-peptide than males. There was a strongly positive correlation between age and some somatometric parameters.

CONCLUSIONS

These physiological data will provide veterinarians and researchers with baseline values to evaluate experimental results using Tibetan macaques.

The changes of glucose and lipid metabolism in overweight middle-aged cynomolgus monkeys

BACKGROUND

Excessive weight gain has been observed in middle-aged cynomolgus monkeys. This study was designed to investigate the metabolic characteristics in overweight monkeys.

METHODS

A total of 26 cynomolgus monkeys were grouped based on gender and body weight. Overweight was operationally defined as body weight heavier than 9.6 kg in males and 7.5 kg in females. They were monitored for glucose and insulin in fasting state, serum parameters, and somatometric measurements.

RESULTS

Higher measurements of weight, body mass index (BMI), waist, hip, and waist/hip ratio (WHR) were the somatometric characteristics of overweight monkeys. Abdominal fat deposition was more prominent in females. Elevated total cholesterol, HDL-C, LDL-C, and fasting glucose were observed in female overweight monkeys. Impaired insulin sensitivity occurred in overweight monkeys.

CONCLUSIONS

Overweight could result in impaired insulin sensitivity. The metabolic changes were more prominent in female overweight monkeys.

Analysis of glucose metabolism in cynomolgus monkeys during aging

This study was designed to investigate the effect of aging on the glucose metabolism on cynomolgus (Macaca fascicularis) monkeys. A total of 33 cynomolgus monkeys in three aged groups were monitored for glucose levels, serum parameters in fasting state and somatometric measurements. Intravenous glucose tolerance test (IVGTT) and insulin tolerance test (ITT) were also performed. Aging associated changes lies in the less secretion of insulin and C-peptide during IVGTT in cynomolgus monkeys. It was also found that impaired insulin sensitivity occurred in female monkeys during aging based on HOMA-IR and K(ITT) value. In addition, triglyceride level also rose with the increase of age. Less insulin secretion and impaired insulin sensitivity in female were the characteristic during the aging of cynomolgus monkeys in this study. Body mass index, weight and waist hip rate may be the relevant factors in insulin resistance of cynomolgus monkeys.

Adiponectin and leptin levels in Chinese patients with HIV-related lipodystrophy: a 30-month prospective study

The relationship of adipocytokine with the development of HIV-related lipodystrophy was investigated in a case-control study. Adipocytokine, lipid, and glycemic parameters were measured at every visit. Logistic regression analysis was used to assess the HIV-LD risk factors and the Spearman correlation coefficients test was used to assess the correlation between adiponectin with other metabolic variables. Most of the patients (96.3%) developed HIV-LD after month 12. Comparing the baseline adiponectin, the adiponectin concentration of the HIV-LD group rose by month 6 and began to decrease substantially by month 18; this reduction was maintained until month 30 (p < 0.05). Comparing the HIV-NLD group, the adiponectin concentration at months 18, 24, and 30 were significantly lower in the HIV-LD group. The leptin concentration of both the HIV-LD and HIV-NLD groups remained stable. Patients in the lower concentration of baseline adiponectin and greater adiponectin change rate at month 18 presented with increased odds ratio for HIV-LD. The adiponectin level had a correlation with serum triglycerides (r = -0.616, p < 0.0001), serum insulin concentration (r = -0.494, p = 0.001), and HDL-C (r = 0.673, p < 0.0001). The adiponectin concentration of HIV-LD began to decrease substantially by month 18. The lower baseline concentration of adiponectin and the greater change rate at month 18 were independent risk factors of HIV-LD. The adiponectin level had a correlation with serum triglycerides, serum insulin concentration, and HDL-C, suggesting that adiponectin may link the metabolic abnormalities and HIV-LD.

How much fat loss is needed for lipoatrophy to become clinically evident?

The objective of this study was to evaluate how much limb fat is needed to be lost for lipoatrophy to become clinically evident. Antiretroviral drug-naive patients from a randomized trial comparing stavudine or abacavir plus lamivudine and efavirenz, who had subjective assessment to detect clinically evident lipoatrophy (standardized questionnaire) and objective measurements of limb fat (dual X-ray absorptiometry) at baseline, 48 weeks, and 96 weeks were included. ROC curves were used to assess the sensitivity and specificity of several cut-off values of absolute and percent limb fat loss for diagnosing lipoatrophy. Of 54 patients included, 13 (24%) had subjective lipoatrophy at 96 weeks. After 96 weeks, median limb fat change was -2.3 kg (interquartile range: -5.2, +0.2) and 0.4 kg (interquartile range: -7.2, +3.4) in patients with and without lipoatrophy, respectively. Median percent limb fat change was -45.5% (interquartile range: -78.0, +3.7) and 5.5% (interquartile range: -62.8, +95.6), respectively. The cut-off values of absolute and percent limb fat loss showing the best sensitivity and specificity values were -1.5 kg (sensitivity, 77%; specificity, 76%) and -30% (sensitivity, 85%; specificity, 73%). At least 30% limb fat is needed to be lost in HIV-infected patients for lipoatrophy to become clinically evident.

Ultrasonographic assessment of lipodystrophy in HIV-1-infected patients

PURPOSE

We performed a cross-sectional study of physical changes in HIV-infected adults to evaluate the role of ultrasonography for the diagnosis of lipodystrophy.

MATERIALS AND METHODS

Sixty HIV-infected patients were recruited from 1 June to 31 December 2006. A total of 34 patients were included in the lipodystrophy group and 26 in no lipodystrophy group. Thickness of subcutaneous fat was measured twice with a high-frequency (15 MHz) transducer by transverse scans at four skin-based reference points: the periumbilical region, the brachial region, the crural region and the malar region. Visceral fat thickness was determined with a low-frequency (3.75 MHz) transducer at two skin reference points: perirenal fat diameter and visceral abdominal fat.

RESULTS

Compared with HIV-infected patients without lipodystrophy, those with lipoatrophy or mixed lipodystrophy had thinner facial, arm and leg fat, whereas patients with lipodystrophy showed thicker intra-abdominal fat. The median of the ratio between intra-abdominal fat and subcutaneous fat and between perirenal fat diameter and body mass index in the lipodystrophy group was higher than in the no lipodystrophy group. The measurements of brachial, malar and crural fat were significantly lower in patients with lipodystrophy.

CONCLUSIONS

We consider the ratio between visceral adipose tissue and subcutaneous adipose tissue and the thickness of malar fat to be the most useful ultrasonographic parameters for the early diagnosis of lipodystrophy in HIV-infected patients on highly active antiretroviral therapy.

Comparability of echographic and tomographic assessments of body fat changes related to the HIV associated adipose redistribution syndrome (HARS) in antiretroviral treated patients

To assess the comparability of ultrasonographic (US) subcutaneous fat thickness (SFT) measurements in comparison with computed tomography (CT) at reference points (RPs) representative of HIV related adipose redistribution syndrome (HARS) in patients treated with antiretrovirals. US and CT measurements were compared in nine patients with clinical reports of HARS. We obtained the best resolution of facial (at deepest point of Bichat pad), brachial (in the dorsal face of arm) and crural SFT (at mid thigh) by means of minimal transducer pressures avoiding potential biases such as stand off pads pressure on the skin and artefacts due to too abundant quantity of gel. CT scans were obtained in the same RP where US measurements were performed such as identified by means of metallic skin markers. Median US measurement of facial SFT was 8.8 mm (95% CI: 3.1 to 13.4), 3.95 mm (95% CI: 2.62 to 5.84) for brachial SFT and 4 mm (95% CI: 3.4 to 9.4) for crural SFT. Median CT assessments of facial SFT was 8.7 mm (95% CI: 3.5 to 13.5), 4.2 mm (95% CI: 2.6 to 5.88) for brachial SFT and 5 mm (95% CI: 3.9 to 10.3) for crural SFT, with no significant difference at each RP. A linear regression showed good CT/US comparability at each RP, with no significant deviation from linearity (p > 0.10). US shows to be highly comparable with CT, excluding invaliding biases as the transducer pressure on the skin. Given the proven efficacy on the HARS assessments, if well standardized, US could be a reliable method, simpler than CT in the management of body fat changes related to HARS.

Predictors of acquired lipodystrophy in juvenile-onset dermatomyositis and a gradient of severity

We describe the clinical features of 28 patients with juvenile dermatomyositis (JDM) and 1 patient with adult-onset dermatomyositis (DM), all of whom developed lipodystrophy (LD) that could be categorized into 1 of 3 phenotypes, generalized, partial, or focal, based on the pattern of fat loss distribution. LD onset was often delayed, beginning a median of 4.6 years after diagnosis of DM. Calcinosis, muscle atrophy, joint contractures, and facial rash were DM disease features found to be associated with LD. Panniculitis was associated with focal lipoatrophy while the anti-p155 autoantibody, a newly described myositis-associated autoantibody, was more associated with generalized LD. Specific LD features such as acanthosis nigricans, hirsutism, fat redistribution, and steatosis/nonalcoholic steatohepatitis were frequent in patients with LD, in a gradient of frequency and severity among the 3 sub-phenotypes. Metabolic studies frequently revealed insulin resistance and hypertriglyceridemia in patients with generalized and partial LD. Regional fat loss from the thighs, with relative sparing of fat loss from the medial thighs, was more frequent in generalized than in partial LD and absent from DM patients without LD. Cytokine polymorphisms, the C3 nephritic factor, insulin receptor antibodies, and lamin mutations did not appear to play a pathogenic role in the development of LD in our patients. LD is an under-recognized sequela of JDM, and certain DM patients with a severe, prolonged clinical course and a high frequency of calcinosis appear to be at greater risk for the development of this complication. High-risk JDM patients should be screened for metabolic abnormalities, which are common in generalized and partial LD and result in much of the LD-associated morbidity. Further study is warranted to investigate the pathogenesis of acquired LD in patients with DM.

Use of Diet, Nutritional Supplements and Exercise in HIV-Infected Patients Receiving Combination Antiretroviral Therapies: A Systematic Review

Background

The use of combination antiretroviral therapy (cART) has improved the prognosis of HIV infection, but it has also been linked to a spectrum of body composition changes and metabolic alterations known as the lipodystrophy syndrome. Nutritional status could influence body composition changes.

Methods

We performed a systematic search of published peer-reviewed data on the effects of diet, nutrition support and exercise on body composition and metabolic complications in patients receiving cART.

Results

Few controlled studies, most of them with small sample size, were found. Oral nutritional support increases protein and energy intake, and results in body weight and fat mass gains. Resistance exercise, with or without an aerobic component, increases lean mass and can improve insulin resistance. Low-fat diets or exercise can result in loss of fat mass, and they should be used with caution in subjects with lipoatrophy.

Conclusions

Nutritional support and exercise result in small but significant body composition changes and can be used as complementary interventions. There is a need for further research on nutritional interventions in HIV-infected patients receiving cART.

HIV-associated adipose redistribution syndrome (HARS): definition, epidemiology and clinical impact

A segment of the HIV infected population develops abnormal and excessive accumulation of adipose tissue in the trunk, including accumulation of visceral (deep abdominal) adipose tissue. This condition, known as HIV-related adipose redistribution syndrome (HARS), may also be accompanied by fat accumulation in the upper back/neck (dorsocervical region) and/or depletion of subcutaneous adipose tissue from the abdomen, face, limbs, or buttocks. HARS is estimated to occur in up to 32% of patients and is associated with health risks similar to those of metabolic syndrome. Techniques to detect and measure HARS include physician and patient assessments and radiologic or anthropometric methods.

Full scope of effect of facial lipoatrophy: a framework of disease understanding

BACKGROUND

Facial lipoatrophy has been observed to occur in a variety of patient populations, with inherited or acquired disease, or even in aging patients as a natural progression of tissue change over time. There is currently no framework from which physicians of all medical specialties can communally discuss the manifestations, diagnoses, and management of facial lipoatrophy.

OBJECTIVE

The aim of this assembly was to derive a definition of facial lipoatrophy capable of being applied to all patient populations and develop an accompanying grading system.

RESULTS

The final consensus of the Facial Lipoatrophy Panel encompasses both aging and disease states: "Loss of facial fat due to aging, trauma or disease, manifested by flattening or indentation of normally convex contours." The proposed grading scale includes five gradations (Grades 1-5; 5 being the most severe), and the face is assessed according to three criteria: contour, bony prominence, and visibility of musculature.

CONCLUSION

Categorizing the presentation of facial lipoatrophy is subjective and qualitative, and will need to be validated with objective measures. Furthermore, during the assembly, several topics were exposed that warrant further research, including the physiology of volume loss, age and lipoatrophy, and human immunodeficiency virus and lipoatrophy.

Facial lipoatrophy and the place of ultrasound

BACKGROUND

Interest in facial lipoatrophy (LA) has recently intensified; this phenomenon is linked to the rise in the number of people adversely affected by the condition as a side effect of antiretroviral treatment for HIV, combined with the growing number of cosmetic products that claim to be able to correct the appearance of LA. Despite growing awareness of the problem, there is at present no standard and accepted technique with which to assess the severity of LA.

OBJECTIVE

This review explores facial LA, the use of ultrasound in the evaluation of facial LA, its advantages and disadvantages, and will place the technique in the context of other means of assessing regional skin and fat thickness.

METHOD

Review of literature published on PubMed. RESULTS Ultrasound, as with any technique used to assess facial LA, is associated with distinct advantages and disadvantages.

CONCLUSIONS

Studies that use a number of different techniques to evaluate changes in dermal thickness provide the greatest insight into both perceived and actual changes in facial LA. Further investigation into the use of these techniques is warranted, along with a formal consensus of facial LA grades.

Interventions for managing antiretroviral therapy-associated lipoatrophy

PURPOSE OF REVIEW

The purpose of this review is to summarize recent data on treatment options for highly active antiretroviral therapy-associated lipoatrophy.

RECENT FINDINGS

Modification of antiretroviral therapy, especially replacing stavudine by abacavir, induces a slow but continuous increase in the subcutaneous fat mass in patients with highly active antiretroviral therapy-associated lipoatrophy. As part of an initial highly active antiretroviral therapy combination, tenofovir and emtricitabine cause less lipodystrophy than stavudine, but no data from controlled studies have yet assessed the effects of switching from older agents to tenofovir or emtricitabine. Novel antidiabetic drugs, glitazones, cause little improvement in highly active antiretroviral therapy-associated lipoatrophy, but increase blood cholesterol and triglyceride concentrations significantly, and thus cannot be recommended for the treatment of highly active antiretroviral therapy-associated lipoatrophy. Various reconstructive procedures have been used to correct facial lipoatrophy. Bioabsorbable fillers have been used successfully, but treatment with such fillers has to be repeated over time. Permanent fillers have a durable effect, but may be difficult or impossible to remove if complications occur. Furthermore, an optimal volume correction with a permanent filler now may prove to be an over-correction in the future, if the recovery process of adipose tissue continues after the modification of antiretroviral therapy.

SUMMARY

The optimal choice of antiretroviral combination is of crucial importance for the prevention and treatment of highly active antiretroviral therapy-associated lipoatrophy. Switching from stavudine to abacavir causes a slow but continuous increase in the subcutaneous fat mass. Bioabsorbable skin fillers are the safest option for the reconstructive treatment of facial lipoatrophy.

Single-Slice Computed Tomography and Anthropometric Skinfold Analysis for Evaluation of Facial Lipoatrophy in HIV-Infected Patients

We assessed the value of computed tomography (CT) and anthropometric skinfold analysis for evaluating subcutaneous facial fat in human immunodeficiency virus-infected patients. Patients with facial lipoatrophy had smaller areas of facial adipose tissue, lower ratios of adipose tissue area to total tissue area of the face, and lower malar skinfold values, compared with patients without facial wasting. CT may be a useful technique to diagnose and monitor facial lipoatrophy.

Mitochondrial Abnormalities in HIV-Infected Lipoatrophic Patients Treated With Antiretroviral Agents

BACKGROUND

Lipodystrophy is now widely described in HIV infected patients under antiretroviral regimen with important psychological impact. But physiopathology of loss of fat mass is still debated and the role of mitochondrial impairment is not clearly defined.

OBJECTIVE

To correlate clinical lipoatrophy (LA) in HIV patients with long-term treatment by nucleoside reverse transcriptase inhibitors (NRTIs) and muscular impairment related to mitochondrial dysfunction.

METHODS

Ten consecutive patients with clinical LA and 10 nonlipodystrophic (NLD) individuals on antiretroviral therapy were included. Patients underwent the following investigations: dual-energy x-ray absorptiometry (DEXA) scanning and lactate kinetics during standardized exercise. The mitochondrial respiratory complex activity (III and IV) and histoenzymatic abnormalities (classified as none, mild, or severe) were evaluated on muscle tissue obtained by biopsy in deltoid muscle.

RESULTS

Mean NRTI exposure was longer in the LA group than in the NLD group (81 +/- 30 months vs. 59 +/- 15 months), but mean protease inhibitor exposure was identical in both groups. Mean fat mass distribution for leg in the LA and NLD groups was 860 +/- 381 g versus 1895 +/- 999 g, respectively. The lactic acidosis threshold during exercise was reached in the LA group at lower workloads (mean: 45 +/- 17 W in the LA group vs. 68 +/- 11 W in the NLD group), and maximum power output exercise was restricted in LA patients (mean: 115 +/- 30 W vs. 153 +/- 28 W). Total complex activities in muscular tissue were lower in LA patients: the median (range) for complex III was 67 (1-128) versus 112 (28-143), and the median (range) for complex IV was 28 (1-70) versus 42 (1-75). Six patients had severe histoenzymatic abnormalities in the LA group versus none in the NLD group.

CONCLUSION

Clinical LA, confirmed by DEXA, in long-term NRTI-treated patients was associated with muscular mitochondrial dysfunction as shown by rapid lactic acidemia increase, impairment of respiratory chain activity for complexes III and IV, and mitochondrial histoenzymatic abnormalities.

Position of the American Dietetic Association and Dietitians of Canada: nutrition intervention in the care of persons with human immunodeficiency virus infection

Infection with the human immunodeficiency virus (HIV) and the development of acquired immunodeficiency syndrome (AIDS) have had a significant impact on domestic and global health, social, political, and economic outcomes. Prevention and treatment efforts to control HIV infection are more demanding than in previous decades. Achieving food and nutrition security, and managing nutrition-related complications of HIV infection and the multiple aspects of disease initiated by or surrounding HIV infection, referred to as HIV disease, remain challenges for patients and for those involved with HIV/AIDS prevention, care, and treatment efforts. Confounding clinical issues include medication interactions, coinfection with other infections and diseases, wasting, lipodystrophy, and others. Dietetics professionals, other health care professionals, and people infected with HIV will need to understand and address multiple complex aspects of HIV infection and treatment to improve survival, body functions, and overall quality of life. Individualized nutrition care plans will be an essential feature of the medical management of persons with HIV infection and AIDS.

HIV Lipodystrophy Syndrome: A Primer

Treatment with highly active antiretroviral therapy (HAART) has been implicated in the development of anthropomorphic and metabolic abnormalities termed HIV lipodystrophy syndrome (or LDS). This primer offers a comprehensive overview of LDS including epidemiology, hypothesized etiologies, and clinical consequences. The evidence-based literature is reviewed for current treatment strategies including discontinuation of specific antiretrovirals, pharmacological management of dyslipidemia and insulin resistance, exercise training, facial augmentation, liposuction, and hormonal therapy. Patient education, counseling, and adherence are discussed.

Risk factors for lipodystrophy in the CISAI cohort

PURPOSE

This study set out to describe the frequency of lipodystrophy, and identify its risk factors, in HIV-positive patients treated with HAART containing at least one protease inhibitor (PI). We analyzed the data collected in the CISAI study.

METHODS

The CISAI is a multicenter cohort study that has enrolled 1480 patients. We assessed whether patients had lipodystrophy at a medical visit, with follow-up visits by the same physician at least every 2 months, and also on the basis of patients' own reports.

RESULTS

The lipodystrophy syndrome was detected in about 25% of the patients. Multivariate analysis showed the risk of lipodystrophy was correlated with female sex (RR 1.5; 95% confidence interval, CI, 1.2-2.1), with older age, with homosexuality (RR 1.5; 95% CI 1.0-2.4), with overt disease (RR 1.4; 95% CI 1.1-1.8) and with the duration of treatment before entering this study. The RR for ritonavir was higher than for the other PI (RR 1.4; 95% CI 0.9-1.9). Among patients receiving concomitant antiretroviral therapy the risk of lipodystrophy was greater with stavudine (RR 1.7; 95% CI 1.3-2.3).

CONCLUSIONS

The study confirmed the high frequency of the lipodystrophy syndrome among patients treated with PI.