RESUMO
CONTEXT: Ectopic fat depots are related to the deregulation of energy homeostasis, leading to diseases related to obesity and metabolic syndrome (MetS). Despite significant changes in body composition over women's lifespans, little is known about the role of breast adipose tissue (BrAT) and its possible utilization as an ectopic fat depot in women of different menopausal statuses. OBJECTIVE: We aimed to assess the relationship between BrAT and metabolic glycemic and lipid profiles and body composition parameters in adult women. METHODS: In this cross-sectional study, we enrolled adult women undergoing routine mammograms and performed history and physical examination, body composition assessment, semi-automated assessment of breast adiposity (BA) from mammograms, and fasting blood collection for biochemical analysis. Correlations and multivariate regression analysis were used to examine associations of BA with metabolic and body composition parameters. RESULTS: Of the 101 participants included in the final analysis, 76.2% were in menopause, and 23.8% were in premenopause. The BA was positively related with fasting plasma glucose, glycated hemoglobin, homeostasis model assessment of insulin resistance, body mass index, waist circumference, body fat percentage, and abdominal visceral and subcutaneous fat when adjusted for age among women in postmenopause. Also, the BA was an independent predictor of hyperglycemia and MetS. These associations were not present among women in premenopause. CONCLUSION: The BA was related to different adverse body composition and metabolic factors in women in postmenopause. The results suggest that there might be a relevant BrAT endocrine role during menopause, with mechanisms yet to be clarified, thus opening up research perspectives on the subject and potential clinical implications.
Assuntos
Adiposidade , Glicemia , Mama , Menopausa , Síndrome Metabólica , Humanos , Feminino , Pessoa de Meia-Idade , Estudos Transversais , Adiposidade/fisiologia , Menopausa/fisiologia , Menopausa/sangue , Menopausa/metabolismo , Adulto , Glicemia/metabolismo , Glicemia/análise , Mama/diagnóstico por imagem , Mama/metabolismo , Síndrome Metabólica/metabolismo , Síndrome Metabólica/sangue , Composição Corporal/fisiologia , Índice de Massa Corporal , Resistência à Insulina/fisiologia , Antropometria , Tecido Adiposo/metabolismoRESUMO
PURPOSE: To evaluate the influence of vitamin D (VD) concentrations coupled with metabolic phenotypes preoperatively and 6 months after Roux-en-Y gastric bypass (RYGB) on body variables and weight loss. MATERIALS AND METHODS: A longitudinal, retrospective, analytical study comprising 30 adult individuals assessed preoperatively (T0) and 6 months (T1) after undergoing Roux-en-Y gastric bypass. The participants were distributed preoperatively into metabolically healthy obese (MHO) and metabolically unhealthy obese individuals (MUHO) according to the HOMA-IR classification, as well as the adequacy and inadequacy of vitamin D concentrations in the form of 25(OH)D. All participants were assessed for weight, height, body mass index (BMI), waist circumference (WC), waist-to-height ratio (WHtR), visceral adiposity index (VAI), body circularity index (BCI), body adiposity index (BAI), weight loss, and assessment of 25(OH)D and 1,25(OH)2D concentrations using high-performance liquid chromatography with an ultraviolet detector (HPLC-UV). The statistical program used was SPSS version 21. RESULTS: VD adequacy and a healthy phenotype in the preoperative period may play an important role concerning body fat distribution, as the body averages for WHtR (0.020*) and BCI (0.020*) were lower in MHO participants. In comparison, those with VD inadequacy and MUHOs had higher BAI averages (0.000*) in the postoperative period. Furthermore, it is possible that VD inadequacy before and after RYGB, even in the presence of an unhealthy phenotype, may contribute to the increase in VAI values (0.029*) after this surgery. Only those with inadequate VD and MUHOs had higher 25(OH)D concentrations. Besides, this unhealthy phenotype had a greater reduction in BMI in the early postoperative period (p < 0.001). CONCLUSION: This study suggests that VD adequacy and the presence of a healthy phenotype appear to have a positive impact on the reduction of visceral fat in the context of pre- and postoperative obesity. In addition, there was a greater weight reduction in those with VD inadequacy and in MUHO, which suggests that the volumetric dilution effect of VD and catabolism after bariatric surgery is more pronounced in this specific metabolic phenotype.
Assuntos
Derivação Gástrica , Obesidade Mórbida , Adulto , Humanos , Vitamina D , Estudos Longitudinais , Obesidade Mórbida/cirurgia , Estudos Retrospectivos , Obesidade/cirurgia , Vitaminas , Índice de Massa Corporal , Redução de Peso , Fenótipo , Obesidade AbdominalRESUMO
Background: Adipose tissue (AT) around and within non-AT organs (i.e., ectopic adiposity) is emerging as a strong risk factor for type 2 diabetes (T2D). Not known is whether major ectopic adiposity depots, such as hepatic, skeletal muscle, and pericardial adiposity (PAT), are associated with T2D independent of visceral adiposity (VAT). More data are particularly needed among high-risk nonobese minority populations, as the race/ethnic gap in T2D risk is greatest among nonobese. Methods: Thus, we measured several ectopic adiposity depots by computed tomography in 718 (mean age = 64 years) African-Caribbean men on the Island of Tobago overall, and stratified by obesity (obese N = 187 and nonobese N = 532). Results: In age, lifestyle risk factors, health status, lipid-lowering medication intake, body mass index and all other adiposity-adjusted regression analyses, and hepatic and skeletal muscle adiposity were associated with T2D among nonobese men only (all P < 0.05), despite no association between VAT and PAT and T2D. Conclusions: Our results support the "ectopic fat syndrome" theory in the pathogenesis of T2D among nonobese African-Caribbean men. Longitudinal studies are needed to clarify the independent role of ectopic adiposity in T2D, and to identify possible biological mechanisms underlying this relationship, particularly in high-risk African ancestry and other nonwhite populations.
Assuntos
Adiposidade , Diabetes Mellitus Tipo 2/fisiopatologia , Gordura Intra-Abdominal/fisiopatologia , Fígado/fisiopatologia , Músculo Esquelético/fisiopatologia , Obesidade/fisiopatologia , Adiposidade/etnologia , Idoso , População Negra , Estudos de Casos e Controles , Estudos Transversais , Diabetes Mellitus Tipo 2/diagnóstico por imagem , Diabetes Mellitus Tipo 2/etnologia , Humanos , Gordura Intra-Abdominal/diagnóstico por imagem , Fígado/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/diagnóstico por imagem , Obesidade/diagnóstico por imagem , Obesidade/etnologia , Prevalência , Medição de Risco , Fatores de Risco , Tomografia Computadorizada por Raios X , Trinidad e Tobago/epidemiologiaRESUMO
BACKGROUND AND AIMS: There is strong evidence that fat accumulating in non-adipose sites, "ectopic fat", is associated with cardiovascular disease (CVD), including vascular calcification. Most previous studies of this association have assessed only a single ectopic fat depot. Therefore, our aim was to assess the association of total, regional, and ectopic fat with abdominal aorto-illiac calcification (AAC) and coronary artery calcification (CAC) in 798 African ancestry men. METHODS: Participants (mean age 62) were from the Tobago Bone Health Study cohort. Adiposity was assessed via clinical examination, dual x-ray absorptiometry, and computed tomography (CT). Ectopic fat depots included: abdominal visceral adipose tissue (VAT), liver attenuation, and calf intermuscular adipose tissue (IMAT). Vascular calcification was assessed by CT and quantified as present versus absent. Associations were tested using multiple logistic regression adjusted for traditional cardiovascular risk factors. Models of ectopic fat were additionally adjusted for total body fat and standing height. RESULTS: All adiposity measures, except VAT, were associated with AAC. Lower liver attenuation or greater calf IMAT was associated with 1.2-1.3-fold increased odds of AAC (p < 0.03 for both), though calf IMAT was a stronger predictor than liver attenuation (p < 0.001) when entered in a single model. No ectopic fat measure was associated with CAC. CONCLUSIONS: Greater adiposity in the skeletal muscle and liver, but not in the visceral compartment, was associated with increased odds of AAC in African ancestry men. These results highlight the potential importance of both quantity and location of adiposity accumulation throughout the body.
Assuntos
Adiposidade/etnologia , Aorta Abdominal , Doenças da Aorta/fisiopatologia , População Negra , Doença da Artéria Coronariana/fisiopatologia , Artéria Ilíaca , Gordura Intra-Abdominal/fisiopatologia , Fígado/fisiopatologia , Músculo Esquelético/fisiopatologia , Calcificação Vascular/fisiopatologia , Absorciometria de Fóton , Adulto , Idoso , Aorta Abdominal/diagnóstico por imagem , Doenças da Aorta/diagnóstico por imagem , Doenças da Aorta/etnologia , Aortografia/métodos , Distribuição de Qui-Quadrado , Angiografia por Tomografia Computadorizada , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/etnologia , Humanos , Artéria Ilíaca/diagnóstico por imagem , Gordura Intra-Abdominal/diagnóstico por imagem , Fígado/diagnóstico por imagem , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/diagnóstico por imagem , Razão de Chances , Estudos Prospectivos , Fatores de Risco , Trinidad e Tobago/epidemiologia , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/etnologiaAssuntos
Doenças Cardiovasculares/diagnóstico por imagem , Doenças Cardiovasculares/epidemiologia , Gordura Intra-Abdominal/diagnóstico por imagem , Adulto , Idoso , Brasil/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Ultrassonografia , Adulto JovemRESUMO
Overall excess of fat, usually defined by the body mass index, is associated with metabolic (e.g. glucose intolerance, type 2 diabetes mellitus (T2DM), dyslipidemia) and non-metabolic disorders (e.g. neoplasias, polycystic ovary syndrome, non-alcoholic fat liver disease, glomerulopathy, bone fragility etc.). However, more than its total amount, the distribution of adipose tissue throughout the body is a better predictor of the risk to the development of those disorders. Fat accumulation in the abdominal area and in non-adipose tissue (ectopic fat), for example, is associated with increased risk to develop metabolic and non-metabolic derangements. On the other hand, observations suggest that individuals who present peripheral adiposity, characterized by large hip and thigh circumferences, have better glucose tolerance, reduced incidence of T2DM and of metabolic syndrome. Insulin resistance (IR) is one of the main culprits in the association between obesity, particularly visceral, and metabolic as well as non-metabolic diseases. In this review we will highlight the current pathophysiological and molecular mechanisms possibly involved in the link between increased VAT, ectopic fat, IR and comorbidities. We will also provide some insights in the identification of these abnormalities. Arq Bras Endocrinol Metab. 2014;58(6):600-9.
Excesso de gordura, geralmente definido pelo índice de massa corporal, está associado a distúrbios metabólicos (p. ex., intolerância à glicose, diabetes melito tipo 2 (DM2), dislipidemia) e não metabólicos (p. ex., neoplasias, síndrome dos ovários policísticos, esteatose hepática não alcoólica, glomerulopatia, fragilidade óssea etc.). No entanto, mais do que sua quantidade total, a forma da distribuição corporal de tecido adiposo constitui-se em um melhor indicador de risco para o desenvolvimento de tais doenças. O acúmulo de gordura na região abdominal e em tecido não adiposo (gordura ectópica), por exemplo, está associado ao aumento de risco para distúrbios metabólicos e não metabólicos. Por outro lado, observações sugerem que os indivíduos que apresentam adiposidade periférica, caracterizada por aumento das circunferências dos quadris e da coxas, têm melhor tolerância à glicose, redução das incidências de DM2 e da síndrome metabólica. Uma das alterações subjacentes na relação entre a obesidade, particularmente a visceral, e os distúrbios citados é a resistência à insulina. Nesta revisão, enfatizaremos os mecanismos fisiopatológicos e moleculares possivelmente implicados na ligação entre o aumento das gorduras visceral e ectópica, IR e comorbidades. Também mencionaremos os métodos diagnósticos mais frequentemente usados na identificação dessas anormalidades. Arq Bras Endocrinol Metab. 2014;58(6):600-9.