Helena Siqueira Vassimon

The association of lipodystrophy and oxidative stress biomarkers in HIV-infected men.

The aim of this study was to describe the status of oxidative stress and antioxidant biomarkers and their association with metabolic and body composition components of HIV-lipodystrophy syndrome. In a cross-sectional study of blood samples from HIV-infected men with lipodystrophy syndrome (HIV+LIPO+ = 10), HIV-infected men without lipodystrophy syndrome (HIV+LIPO- = 22), and healthy subjects (control = 12), the following oxidative stress biomarkers were analyzed: total hydroperoxide, thiobarbituric acid reactive substances (TBARS), and advanced oxidation protein products (AOPP). In addition, antioxidant biomarkers, including total glutathione, uric acid, alpha-tocopherol, and metabolic components were tested. Dual-energy x-ray absorciometry (DXA) was used to measure the fat mass. The duration of HIV infection and the duration and type of highly active antiretroviral therapy were similar between the two HIV-infected groups. Higher levels of total hydroperoxide were observed in the HIV+LIPO+ (50 +/- 33 H(2)O(2)/L) group compared to the HIV+LIPO- (19 +/- 13 H(2)O(2)/L) and control (5 +/- 5 H(2)O(2)/L) groups (p < 0.05). Similarly, higher levels of AOPP were observed in the HIV+LIPO+ (326 +/- 173 micromol/L) group compared to the HIV+LIPO- (105 +/- 92 micromol/L) and control groups (80 +/- 20 micromol/L) (p < 0.05). Total hydroperoxide significantly correlated with insulin serum levels in the HIV+LIPO+ (r = 0.47, p < 0.05) and HIV+LIPO- groups (r = 0.29, p < 0.05), while AOPP significantly correlated with insulin serum levels in the HIV+LIPO+ (r = 0.73, p < 0.05) and HIV+LIPO- (r = 0.54, p < 0.05) groups. Therefore, higher lipid and protein oxidation were found in HIV-infected patients with lipodystrophy syndrome, and both were associated with insulin levels.

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

OBJECTIVE Human immunodeficiency virus type 1 (HIV)-associated lipodystrophy syndrome compromises body composition and produces metabolic alterations, such as dyslipidemia and insulin resistance. This study aims to determine whether energy expenditure and substrate oxidation are altered due to human HIV-associated lipodystrophy syndrome. METHODS We compared energy expenditure and substrate oxidation in 10 HIV-infected men with lipodystrophy syndrome (HIV+LIPO+), 22 HIV-infected men without lipodystrophy syndrome (HIV+LIPO-), and 12 healthy controls. Energy expenditure and substrate oxidation were assessed by indirect calorimetry, and body composition was assessed by dual-energy X-ray absorptiometry. The substrate oxidation assessments were performed during fasting and 30 min after eucaloric breakfast consumption (300 kcal). RESULTS The resting energy expenditure adjusted for lean body mass was significantly higher in the HIV+LIPO+ group than in the healthy controls (P = 0.02). HIV-infected patients had increased carbohydrate oxidation and lower lipid oxidation when compared to the control group (P < 0.05) during fasting conditions. After the consumption of a eucaloric breakfast, there was a significant increase in carbohydrate oxidation only in the HIV+LIPO- and control groups (P < 0.05), but there was no increase in the HIV+LIPO+ group. CONCLUSION Hypermetabolism and alteration in substrate oxidation were observed in the HIV+LIPO+ group.

Proposed ratios and cutoffs for the assessment of lipodystrophy in HIV-seropositive individuals

Objectives:To propose objective ratios using anthropometry and dual-energy X-ray absorptiometry (DXA) and to suggest cutoff points for them in order to classify lipodystrophy in male patients.Methods:It is a cross-sectional study. DXA was applied and anthropometric measurements were performed in 100 men on highly active antiretroviral therapy. Receiver operating characteristic curves were used to propose cutoffs. Individuals were divided in without (lipo−) or with (lipo+) lipodystrophy and their metabolic parameters were compared.Results:The following ratios were proposed: fat mass ratio by DXA (FMR), waist thigh ratio (WTR), waist calf ratio (WCR), and arm to trunk ratio (ATR). The best cutoffs observed for FMR, WTR and ATR were 1.26, 1.74 and 2.08, respectively. Using the proposed cutoff for FMR, we observed worse metabolic profile, with increased tryglicerides, fasting serum glucose and more hypercholesterolemia in the lipo+ group. WTR and ATR showed a significant correlation with FMR.Conclusions:Anthropometric ratios (WTR/ATR) and FMR can be used to aid the diagnosis of lipodystrophy in order to contribute to a more accurate and earlier diagnosis permitting intervention and even preventing metabolic disturbances.

Plasma homocysteine levels in HIV-infected men with and without lipodystrophy

OBJECTIVE Lipodystrophy syndrome is an unexpected clinical manifestation in patients infected with HIV and might be a clinical marker of increased risk for cardiovascular diseases (CVDs). Because hyperhomocysteinemia has been associated with CVD, the goal of the present study was to investigate homocysteine (Hcy) levels and their association with the factors of lipodystrophy syndrome in men with HIV. METHODS Hcy metabolism-related molecules were determined in 13 men infected with HIV with lipodystrophy (HIV+LIP), 10 men with HIV without lipodystrophy (HIV), and 10 healthy controls (C). RESULTS Significant (P < 0.05) increased Hcy plasma levels were found in HIV (20.5%) and in HIV+LIP (35.2%) compared with the control group. Plasma levels of vitamin B12 (HIV, 26.5%; HIV+LIP, 28.8%) and folate (HIV, 39.1% and HIV+LIP, 49.4%) were significantly (P < 0.05) lower in the two groups of HIV patients compared with control. HIV+LIP men presented raised plasma total sulfur-containing amino acids (20.1%) and lower total plasma thiol (11.3%) than controls. The same was not observed in the HIV group. Spearmans correlation test revealed significant (P < 0.05) association between plasma Hcy and duration of highly active antiretroviral therapy (HAART) and plasma insulin, as well as plasma adiponectin levels. CONCLUSION Our results demonstrated that HIV+LIP men were more susceptible to disturbances in Hcy metabolism compared with men infected with HIV without lipodystrophy characteristics. Duration of HAART treatment, elevated plasma insulin, and low levels of adiponectin seem to be relevant for the appearance of these Hcy metabolic disorders.

ANTHROPOMETRY AND BIOELECTRICAL IMPEDANCE ANALYSIS COMPARED TO DUAL-PHOTON ABSORPTIOMETRY FOR THE ASSESSMENT OF BODY COMPOSITION OF HIV-SEROPOSITIVE PATIENTS

Introduccion: Se ha descrito cambios en la composicion corporal de pacientes infectados por VIH, tales como la lipoatrofia en ciertas regiones del cuerpo y lipohipertrofia en otros, en representacion de las caracteristicas del sindrome de lipodistrofia. Es importante controlar la cantidad de grasa corporal por segmento utilizando metodos practicos y de bajo costo con el fin de optimizar el tratamiento de este grupo. Objetivos: correlacionar la composicion corporal por segmento corporal obtenidos por las mediciones antropometricas y por impedancia bioelectrica com DXA segmentaria en pacientes seropositivos al VIH en tratamiento antir-retroviral. Metodos: Se midieron las circunferencias de brazo, cintura, cadera, muslo y pantorrilla y los pliegues cutaneos: biceps, triceps, subescapular, suprailiaco) y se realizaron impedancia bioelectrica segmentaria (BIA) el analisis y DXA. La prueba de Pearson se utilizo para determinar las correlaciones y la prueba de San Lorenzo se utilizo para evaluar la concordancia entre las variables. Resultados: Se evaluaron 26 pacientes, 35% de los cuales tenian sobrepeso. El pliegue del triceps (PT), circunferencia de la cintura (CC) y la circunferencia del muslo (CM) se correlacionaron significativamente con la medida obtenida por el patron de oro (p <0.01). No hubo concordancia entre los valores obtenidos por BIA y DXA segmentaria. Conclusiones: Las mediciones antropometricas como PT, CC y CM son importantes para el seguimiento de los cambios en la composicion corporal de los pacientes infectados por VIH que reciben tratamiento antirretroviral. La BIA segmental no demostro ser adecuado para la evaluacion de la composicion corporal en pacientes infectados por VIH.

Redistribuição de gordura corporal e alterações no metabolismo de lipídeos e glicose em pessoas vivendo com HIV/AIDS

INTRODUCTION The HIV lipodystrophy syndrome is characterized by changes in metabolism, and body composition that increase cardiovascular risk of people living with HIV/AIDS (PLWHA) using highly active antiretroviral therapy (HAART). OBJECTIVE To assess the prevalence of lipodystrophy and changes in lipid and glucose metabolism in PLWHA in use of HAART. METHODS For the anthropometric evaluation we measured weight, height and abdominal circumference (AC). For the lipodystrophy evaluation we conducted physical examination (subjective) and the (objective) examination of absorptiometry with X-ray dual energy (DEXA) by fat mass ratio (FMR). We also conducted lipid profile tests and fasting glucose and used the criteria suggested by The National Cholesterol Education Program III for metabolic disorders classification. RESULTS The final sample consisted of 262 patients with a mean age of 44.3 ± 10.2 years. Lipodystrophy, according to the physical examination, was present in 47.7% (95%CI 41.7 - 53.8) of patients, while the prevalence using FMR (DEXA) was 40.8% (95%CI 33.1 - 48.5). Most (53.0%; 95%CI 47.0 - 59.1) of the patients showed increased abdominal adiposity according to AC. The most prevalent metabolic alterations were reduced HDL (67.6%; 95%CI 61.9 - 73.2) and hypertriglyceridemia (55.7%; 95%CI 49.7 - 61.7). CONCLUSION The high prevalence of lipodystrophy and changes in lipid and glucose metabolism show the importance of early intervention in this group of patients to prevent cardiovascular complications.RESUMO: Introducao: A sindrome da lipodistrofia do HIV e caracterizada por alteracoes no metabolismo e na composicao corporal, que aumentam o risco cardiovascular de pessoas vivendo com HIV/AIDS (PVHA) em uso da terapia antirretroviral de alta potencia (TARV). Objetivo: Avaliar a prevalencia de lipodistrofia e de alteracoes do metabolismo de lipidios e glicose em PVHA em uso da TARV. Metodos: Para avaliacao antropometrica foram aferidos peso, estatura e circunferencia abdominal (CA). Para avaliacao da lipodistrofia foi realizado o exame fisico (subjetivo) e o exame (objetivo) de absortometria com raios X de dupla energia (DEXA) por meio da razao de massa gorda (RMG). Foram tambem realizados exames de lipidograma e glicemia de jejum e utilizados os criterios sugeridos pelo The National Cholesterol Education Program III para classificacao de alteracoes metabolicas. Resultados: A amostra final consistiu em 262 pacientes com idade media de 44,3 ± 10,2 anos. A lipodistrofia, de acordo com o exame fisico, esteve presente em 47,7% (IC95% 41,7 - 53,8) dos pacientes, enquanto pela RMG (DEXA) sua prevalencia foi de 40,8% (IC95% 33,1 - 48,5). A maioria (53,0%; IC95% 47,0 - 59,1) dos pacientes apresentou aumento de adiposidade abdominal segundo a CA. As alteracoes metabolicas mais presentes foram o HDL reduzido (67,6%; IC95% 61,9 - 73,2) e a hipertrigliceridemia (55,7%; IC95% 49,7 - 61,7). Conclusoes: A alta prevalencia de lipodistrofia e alteracoes do metabolismo de lipidios e glicose evidenciam a importância da intervencao precoce nesse grupo de pacientes para prevenir complicacoes cardiovasculares.

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.

INGESTÃO ALIMENTAR, PERFIL BIOQUÍMICO E ESTADO NUTRICIONAL ENTRE VEGETARIANOS E NÃO VEGETARIANOS

Introduction: Vegetarian diets are associated with great health benefits. Objective: The aim of the present study is to compare food intake, lipid profile, blood glucose, blood pressure and anthropometry among vegetarians and non vegetarians. Patients and Methods: It was selected 20 vegetarians and 22 omnivorous. Food intake was evaluated by 24 hours recall. Lipid profile and glycemia were analyzed, also blood pressure and anthropometry (arm and waist circumferences, triceps skinfold thickness, height and weight) were measured. Results: From the vegetarian group, 75% were lacto-ovo-vegetarians; 15% were lacto-vegetarians, and 10% were vegans. Lipid profile, glycemia and blood pressure were not significantly different between groups. The vegetarian group showed a lower body mass index (23 ± 4 kg/m2) than the omnivorous group (27 ± 5 kg/m2). The vegetarian group had a higher intake of fiber and polyunsaturated fat, and lower intake of zinc, phosphorus, niacin, riboflavin than omnivorous individuals. For both groups, it was not achieved recommendations from various nutrients. Conclusion: Vegetarian had a higher intake of fiber and polyunsaturated fat and did not present lipid profile, glycemia or blood pressure alterations. However, only meat exclusion, does not necessarily reflect upon a healthy eating pattern. It depends on other factors.

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

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 valuesobtained by indirect calorimetry as the gold standard and those obtained by predictive equations elaboratedfrom data for the healthy population: Harris-Benedict, Schofield and Cunningham, and by equations elaboratedfrom data for HIV-infected patients: Melchior (1991-1993).