Validation of the measurement of intra-abdominal fat between ultrasound and CT scan in women with obesity and infertility

Influence of Adipose Tissue on Early Metabolic Programming: Conditioning Factors and Early Screening

BACKGROUND

Obesity and being overweight have become one of the world's most severe health issues, not only because of the pathology but also because of the development of related comorbidities. Even when children reach adulthood, the mother's environment during pregnancy has been found to have a significant impact on obesity prevention in children. Thus, both maternal dietary habits and other factors such as gestational diabetes mellitus, excessive weight gain during pregnancy, smoking, or endocrine factors, among others, could influence newborn growth, adiposity, and body composition at birth, in childhood and adolescence, hence programming health in adulthood.

METHODS

The aim of this review is to analyze the most recent human studies on the programming of fetal adipose tissue to determine which modifiable factors may influence adiposity and thus prevent specific disorders later in life by means of a bibliographic review of articles related to the subject over the last ten years.

CONCLUSIONS

The importance of a healthy diet and lifestyle not only during pregnancy and the first months of life but also throughout childhood, especially during the first two years of life as this is a period of great plasticity, where the foundations for optimal health in later life will be laid, preventing the emergence of noncommunicable diseases including obesity, diabetes mellitus type 2, hypertension, being overweight, and any other pathology linked to metabolic syndrome, which is so prevalent today, through health programs beginning at a young age.

Ultrasound estimated subcutaneous and visceral adipose tissue thicknesses and risk of pre-eclampsia

Early identification of high-risk pregnancies enables identification of those who would benefit from aspirin prophylaxis and increased surveillance for pre-eclampsia. A high body mass index (BMI) is a well-known predictor for pre-eclampsia. However, if abdominal adipose tissue distribution is associated with pre-eclampsia is limited investigated. Subcutaneous adipose tissue (SAT) thickness and visceral adipose tissue (VAT) thickness were measured by ultrasound on 3777 women at around 18 gestational weeks. SAT thickness was measured from the skin to linea alba and VAT from linea alba to the anterior aortic wall. The risk of developing pre-eclampsia (de novo hypertension at ≥ 20 gestational weeks in combination with proteinuria) was evaluated by logistic regression and expressed as odds ratio (OR) with 95% confidence intervals (CI). The risk of pre-eclampsia increased by 79% for every cm in SAT thickness (OR 1.79; 95% CI 1.48-2.17) and by 23% for every cm VAT thickness (OR 1.23; 95% CI 1.11-1.35). After adjustment for maternal age, parity, BMI, smoking and country of birth, the association between SAT thickness and pre-eclampsia remained (AOR 1.35; 95% CI 1.02-1.79). Greater SAT thickness measured with second trimester ultrasound is associated with increased risk of developing pre-eclampsia. The measurement may improve prediction models for pre-eclampsia.

Hepatic Steatosis in Patients With Single Ventricle and a Fontan Circulation

Background

Hepatic steatosis, caused by nonalcoholic fatty liver disease, is a leading cause of chronic liver disease. The interplay between hepatic steatosis and the development of liver disease following the Fontan procedure is not well understood. This study examined the prevalence and associations of hepatic steatosis in patients with a Fontan circulation.

Methods and Results

This was a single‐center retrospective study of 95 patients with a Fontan circulation with liver magnetic resonance imaging performed between 2012 and 2019. The average age at magnetic resonance imaging was 21.5±8.5 years. The percent liver fat signal was determined using magnetic resonance chemical shift‐encoded proton density fat fraction imaging. Hepatic steatosis was defined as liver fat ≥5% and was present in 10.5% of the cohort. The presence of hepatic steatosis was associated with higher body mass index (29±4 versus 24±6 kg/m², P=0.006), a higher frequency of obesity (50% versus 12%, P=0.015), lower high‐density lipoprotein cholesterol (35±9 versus 43±14 mg/dL, P=0.050), and greater subcutaneous fat thickness (2.6±0.7 versus 1.8±1.0 cm, P=0.043). There was no association between hepatic steatosis and cardiovascular imaging or hemodynamic variables from cardiac catheterization.

Conclusions

Risk factors for hepatic steatosis in patients with Fontan circulation include obesity and dyslipidemia, similar to what is seen in the general population. Fontan hemodynamics were not associated with hepatic steatosis.

Relation of visceral fat and haemodynamics in adults with Fontan circulation

Being overweight is associated with reduced functional capacity in Fontan patients. Increased adiposity leads to accumulation of epicardial and intra-abdominal visceral fat, which produce proinflammatory cytokines and may affect endothelial function. This retrospective study to evaluate the association between visceral fat and Fontan haemodynamics included 23 Fontan patients >18 years old with MRI and catheterization data available. Epicardial fat volume indexed to body surface area was measured by cardiac MRI, and intra-abdominal visceral fat thickness and subcutaneous fat thickness were derived from abdominal MRI. Stepwise regression models were used to determine univariable and multivariable associations between fat measures and haemodynamics. Mean age was 28.2 ± 9.5 years and body mass index was 26 ± 4 kg/m2. Mean central venous pressure was 13 ± 3 mmHg and pulmonary vascular resistance index was 1.23WU·m2 (interquartile range: 0.95-1.56). Epicardial fat volume was associated with age (r2 = 0.37, p = 0.002), weight (r2 = 0.26, p = 0.013), body mass index (r2 = 0.27, p = 0.011), and intra-abdominal visceral fat (r2 = 0.30, p = 0.018). Subcutaneous fat thickness did not relate to these measures. There was modest correlation between epicardial fat volume and pulmonary vascular resistance (r2 = 0.27, p = 0.02) and a trend towards significant correlation between intra-abdominal fat thickness and pulmonary vascular resistance (r2 = 0.21, p = 0.06). Subcutaneous fat thickness was not associated with Fontan haemodynamics. In multivariable analysis, including age and visceral fat measures, epicardial fat was independently correlated with pulmonary vascular resistance (point estimate 0.13 ± 0.05 per 10 ml/m2 increase, p = 0.03). In conclusion, in adults with Fontan circulation, increased visceral fat is associated with higher pulmonary vascular resistance. Excess visceral fat may represent a therapeutic target to improve Fontan haemodynamics.

Intra-Abdominal Adipose Tissue Quantification by Alternative Versus Reference Methods: A Systematic Review and Meta-Analysis

OBJECTIVE

This meta-analysis aimed to assess the agreement between intra-abdominal adipose tissue (IAAT) quantified by alternative methods and the reference standards, computed tomography (CT) and magnetic resonance imaging (MRI).

METHODS

MEDLINE and EMBASE electronic databases were systematically searched to identify studies that quantified IAAT thickness, area, or volume by a comparator method and CT or MRI. Using an inverse variance weighted approach (random-effects model), the mean differences and 95% limits of agreement (LoA) were pooled between methods.

RESULTS

The meta-analysis included 24 studies using four comparator methods. The pooled mean differences were -0.3 cm (95% LoA: -3.4 to 3.2 cm; P = 0.400) for ultrasound and -11.6 cm² (95% LoA: -43.1 to 19.9 cm² ; P = 0.004) for bioelectrical impedance analysis. Dual-energy x-ray absorptiometry (DXA) quantified both IAAT area and volume with mean differences of 8.1 cm² (95% LoA: -98.9 to 115.1 cm² ; P = 0.061) and 10 cm³ (95% LoA: -280 to 300 cm³ ; P = 0.808), respectively.

CONCLUSIONS

Ultrasound and DXA measure IAAT with minimal bias from CT or MRI, while bioelectrical impedance analysis systematically underestimates IAAT. However, with the exception of DXA for IAAT volume, the wide LoA caution against clinical or research use of the comparator methods and emphasize the need to optimize alternatives to the reference standards.

Ultrasonography Technique in Abdominal Subcutaneous Adipose Tissue Measurement: A Systematic Review

There are currently several reported techniques of sonographic subcutaneous adipose tissue (SAT) measurement described in the literature. This systematic review aims to report techniques of SAT measurement using ultrasonography. A systematic literature search was performed and identified 39 relevant articles using ultrasonography to quantify abdominal SAT. The following parameters were collected: type of measurement, ultrasound machine make/model, transducer frequency, external/internal landmarks, pressure applied on probe, special techniques and inter-/intraobserver reliability. Literature findings related to the above parameters were summarized. A summary of the most common techniques and parameters is provided, serving as a reference for a necessary standardized approach.

Objective Quantification of Liposuction Results

Currently, no reliable gold standard exists for the objective outcome measurement following liposuction. The purpose of this systematic review was to summarize reported methods of monitoring liposuction results by objectively measuring subcutaneous adipose tissue. A systematic literature search was performed to identify relevant articles that described techniques for objectively quantifying adipose tissue following traditional liposuction. The search included published articles in three electronic databases—Ovid MEDLINE, Embase, and PubMed. Subcutaneous adipose tissue was estimated using the following techniques: ultrasound, dual-energy X-ray absorptiometry, magnetic resonance imaging, computed tomography, and three-dimensional imaging volumetric analysis. Reported benefits of liposuction objective measurements included providing patients with a quantitative assessment of the liposuction results pre- and postoperatively, detecting significant changes in body fat deposits, and following patterns of fat redistribution. This review provides a summary of various techniques for quantification of liposuction results. More studies are needed to study the clinical relevancy and impact of the various imaging modalities reviewed as well as to develop automated volumetric measurement technology with improved accuracy, efficacy, and reproducibility.

Diagnostic imaging in the management of patients with metabolic syndrome

Metabolic syndrome (MetS) is the constellation of metabolic risk factors that might foster development of type 2 diabetes and cardiovascular disease. Abdominal obesity and insulin resistance play a prominent role among all metabolic traits of MetS. Because intervention including weight loss can reduce these morbidity and mortality in MetS, early detection of the severity and complications of MetS could be useful. Recent advances in imaging modalities have provided significant insight into the development and progression of abdominal obesity and insulin resistance, as well as target organ injuries. The purpose of this review is to summarize advances in diagnostic imaging modalities in MetS that can be applied for evaluating each components and target organs. This may help in early detection, monitoring target organ injury, and in turn developing novel therapeutic target to alleviate and avert them.

Women, their Offspring and iMproving lifestyle for Better cardiovascular health of both (WOMB project): a protocol of the follow-up of a multicentre randomised controlled trial

INTRODUCTION

Women, their Offspring and iMproving lifestyle for Better cardiovascular health of both (WOMB) project is the follow-up of the LIFEstyle study, a randomised controlled trial in obese infertile women, and investigates the effects of a preconception lifestyle intervention on later health of women (WOMB women) and their children (WOMB kids).

METHODS AND ANALYSIS

Obese infertile women, aged between 18 and 39 years, were recruited in 23 Dutch fertility clinics between June 2009 and June 2012. The 284 women allocated to the intervention group received a 6-month structured lifestyle programme. The 280 women in the control group received infertility care as usual. 4 to 7 years after inclusion in the trial, all women (n=564) and children conceived during the trial (24 months after randomisation) (n=305 singletons and age 3-5 years) will be approached to participate in this follow-up study (starting in 2015). The main focus of outcome will be cardiovascular health, but the dataset comprises a wide range of physical and mental health measures, diet and physical activity measures, child growth and development measures, biological samples and genetic and epigenetic information. The follow-up assessment consists of three stages that take place between 2016 and 2018, and includes (online) questionnaires, accelerometry and physical and behavioural measurements in a mobile research vehicle. A subsample of 100 women and 100 children are planned for cardiac ultrasound measurements.

ETHICS AND DISSEMINATION

The protocol of this follow-up study is approved by the local medical ethics committee (University Medical Centre Groningen). Study findings of the WOMB project will be widely disseminated to the scientific community, healthcare professionals, policy makers, future parents and general public.

TRIAL REGISTRATION NUMBER

The original LIFEstyle study is registered at The Netherlands Trial Registry (number 1530).

Randomized Trial of a Lifestyle Program in Obese Infertile Women

BACKGROUND

Small lifestyle-intervention studies suggest that modest weight loss increases the chance of conception and may improve perinatal outcomes, but large randomized, controlled trials are lacking.

METHODS

We randomly assigned infertile women with a body-mass index (the weight in kilograms divided by the square of the height in meters) of 29 or higher to a 6-month lifestyle intervention preceding treatment for infertility or to prompt treatment for infertility. The primary outcome was the vaginal birth of a healthy singleton at term within 24 months after randomization.

RESULTS

We assigned women who did not conceive naturally to one of two treatment strategies: 290 women were assigned to a 6-month lifestyle-intervention program preceding 18 months of infertility treatment (intervention group) and 287 were assigned to prompt infertility treatment for 24 months (control group). A total of 3 women withdrew consent, so 289 women in the intervention group and 285 women in the control group were included in the analysis. The discontinuation rate in the intervention group was 21.8%. In intention-to-treat analyses, the mean weight loss was 4.4 kg in the intervention group and 1.1 kg in the control group (P<0.001). The primary outcome occurred in 27.1% of the women in the intervention group and 35.2% of those in the control group (rate ratio in the intervention group, 0.77; 95% confidence interval, 0.60 to 0.99).

CONCLUSIONS

In obese infertile women, a lifestyle intervention preceding infertility treatment, as compared with prompt infertility treatment, did not result in higher rates of a vaginal birth of a healthy singleton at term within 24 months after randomization. (Funded by the Netherlands Organization for Health Research and Development; Netherlands Trial Register number, NTR1530.).

Waist circumference, visceral abdominal fat thickness and three components of metabolic syndrome

OBJECTIVE

The relationships between the waist circumference (WC), visceral adipose tissue (VAT) thickness and three components of metabolic syndrome (MetS) were explored to verify which of the obesity indices might be superior.

METHODS

A cross-sectional study was conducted of 1256 subjects (840 males and 416 females) aged 26-89 years, who were individuals undergoing intensive health checkup. The three components of MetS examined were high blood pressure, glucose intolerance and dyslipidemia. Receiver-operating characteristic (ROC) curve analysis and multiple logistic regression analysis were used for the analyses.

RESULTS

The mean values of the WC and VAT thickness were significantly higher in the subject group positive for each of the metabolic syndrome components than in the subject group that was negative for all the components (p<0.001). ROC curve analysis showed that the WC showed an advantage over the VAT thickness only for predicting high blood pressure in men. Logistic regression analysis revealed increase of the odds ratios of the WC for glucose intolerance (p<0.001), high blood pressure (p<0.001) and dyslipidemia (p<0.01) in men. In contrast, the odds ratio of the VAT thickness was significantly increased only for dyslipidemia (p<0.01) in men. In women, the odds ratios of the WC for glucose intolerance (p<0.01) and dyslipidemia (p<0.001) were significantly increased, and odds ratio of the VAT thickness for high blood pressure (p<0.01) was significantly increased.

CONCLUSION

This survey presented an advantage of WC over VAT thickness as an obesity index for identifying all the three components of metabolic syndrome, although sex differences in the study outcomes were found.

Imaging methods for analyzing body composition in human obesity and cardiometabolic disease

Advances in the technological qualities of imaging modalities for assessing human body composition have been stimulated by accumulating evidence that individual components of body composition have significant influences on chronic disease onset, disease progression, treatment response, and health outcomes. Importantly, imaging modalities have provided a systematic method for differentiating phenotypes of body composition that diverge from what is considered normal, that is, having low bone mass (osteopenia/osteoporosis), low muscle mass (sarcopenia), high fat mass (obesity), or high fat with low muscle mass (sarcopenic obesity). Moreover, advances over the past three decades in the sensitivity and quality of imaging not just to discern the amount and distribution of adipose and lean tissue but also to differentiate layers or depots within tissues and cells is enhancing our understanding of distinct mechanistic, metabolic, and functional roles of body composition within human phenotypes. In this review, we focus on advances in imaging technologies that show great promise for future investigation of human body composition and how they are being used to address the pandemic of obesity, metabolic syndrome, and diabetes.