Body mass index versus waist circumference as predictors of mortality in Canadian adults

Association of waist circumference and BMI with premature death in young and middle-aged population

Introduction

Premature death is a global health indicator, significantly impacted by obesity, especially in young and middle-aged population. Both body mass index (BMI) and waist circumference (WC) assess obesity, with WC specifically indicating central obesity and showing a stronger relationship with mortality. However, despite known associations between BMI and premature death, as well as the well-recognized correlation between WC and adverse health outcomes, the specific relationship between WC and premature death remains unclear. Therefore, focusing on young and middle-aged individuals, this study aimed to reliably estimate independent and combined associations between WC, BMI and premature death, thereby providing causal evidence to support strategies for obesity management.

Methods

This study involved 49,217 subjects aged 18-50 years in the United States from 1999 to 2018 National Health and Nutrition Examination Survey (NHANES). Independent and combined associations between WC and BMI with premature death across sex and age stratum were examined by Cox regression. Survey weighting and inverse probability weighting (IPW) were further considered to control selection and confounding bias. Robustness assessment has been conducted on both NHANES and China Health and Retirement Longitudinal Study (CHARLS) data.

Results

A linear and positive relationship between WC and all-cause premature death was found in both males and females, with adjusted HRs of 1.019 (95%CI = 1.004-1.034) and 1.065 (95%CI = 1.039-1.091), respectively. Nonlinear relationships were found with respect to BMI and all-cause premature death. For females aged 36-50 with a BMI below 28.6 kg/m2, the risk of premature death decreased as BMI increased, indicated by adjusted HRs of 0.856 (95%CI = 0.790-0.927). Joint analysis showed among people living with obesity, a larger WC increased premature death risk (HR = 1.924, 95%CI = 1.444-2.564).

Discussion

WC and BMI exhibited prominent associations with premature death in young and middle-aged population. Maintaining an appropriate WC and BMI bears significant implications for preventing premature death.

Adiposity trajectories and cardiovascular disease risk in women: a population-based cohort study with a focus on menopausal status

Objectives

A single measurement of adiposity indices could predict the incidence of cardiovascular disease (CVD); nonetheless their long-term pattern and its association with incident CVD are rarely studied. This study aimed to determine distinct trajectories of adiposity indices among participants of Tehran Lipid and Glucose Study (TLGS) and their association with incident CVD. Furthermore, this study aimed to investigate whether this association differed among individuals according to their menopausal status.

Method

A total of 6840 women participated in TLGS, aged 20 years and older were included in this study; they were followed for a median of 16 years. Body mass index (BMI), waist circumference (WC), conicity index (CI) and body roundness index (BRI) were included in the analysis as adiposity indices. The cohort outcome panel of medical specialists identified the CVD outcomes. Trajectory analyses were used to identify homogeneous distinct clusters of adiposity indices trajectories. The association between the trajectory group membership and incident CVD were explored by Cox proportional hazard models, with unadjusted and adjusted model for baseline age, physical activity, smoking status, menopause and family history of CVD.

Results

Three BMI trajectory groups of low, medium, and high and two trajectories for WC, BRI and CI were identified. Adjusted cox proportional hazard models revealed significant associations between the hazard of CVD experience and the high trajectory group of the BMI (HR: 2.06, 95% CI: 1.38-3.07), WC (HR: 2.71, 95% CI: 1.98-3.70), CI (HR: 1.87, 95% CI: 1.26-2.77) and BRI (HR: 1.55-95% CI: 1.12-2.15), compared to the low trajectory group. Subgroup analysis based on the menopausal status of participants showed that the HR of CVD incidences for all of trajectories adiposity indices, except BMI, was statistically significant. Adjusted cox proportional hazard models, in those women not reached menopause during study, revealed that the HR (95% CI) of CVD incidences for high trajectory of BMI, WC, CI and BRI were 2.80 (1.86-7.05); 2.09 (1.40-6.16); 1.72 (1.42-5.61), and 3.09 (1.06-9.01), respectively. These values for those were menopause at the initiation of the study were 1.40 (1.11, 2.53); 1.65 (1.04-2.75); 1.69 (1.01-2.87), and 1.61 (0.98-2.65), respectively.

Conclusion

Our findings suggest that adiposity trajectories, particularly central adiposity index of CI, could precisely predict the CVD risk. Consequently, preventive strategies should be tailored accordingly.

Association of Waist Circumference and Body Mass Index Deciles Ratio with All-Cause Mortality: Findings from the National Health and Nutrition Examination Survey

Given the importance and continued interest in finding a simple, accessible, and universal measure which reflects both general and abdominal adiposity, this study tested for an association of the ratio of WC decile to BMI decile (WC-d/BMI-d) with all-cause mortality. Individuals aged 18-79 years who had participated in the National Health and Nutrition Examination Survey (NHANES) during the years 2007 to 2018 were included in the analysis. WC and BMI deciles were defined separately for males and females, while WC-d/BMI-d was calculated for each individual. The association of WC-d/BMI-d with mortality was assessed using logistic models for the total study population, and then again after stratification by sex, ethnicity, morbidity level, and BMI categories. Positive associations between WC-d/BMI-d and mortality were demonstrated for the total study population (adjusted OR = 1.545, 95%CI: 1.369-1.722) and within different sub-groups, including the population with a normal BMI level (adjusted OR = 1.32, 95%CI: 1.13-1.50). WC-d/BMI-d increased with age, with ~40 years representing a critical time point when WC-d surpasses BMI-d, with a sharper incline for males as compared to females. WC-d/BMI-d was significantly associated with all-cause mortality amongst NHANES American adults; thus, measurements of WC and its integration with BMI in this metric should be considered in clinical practice.

Comparative efficacy of exercise training modes on systemic metabolic health in adults with overweight and obesity: a network meta-analysis of randomized controlled trials

Objective

This network meta-analysis (NMA) was conducted to compare and rank the effects of training interventions including aerobic exercise (AE), resistance training (RT), combined aerobic and resistance training (CT), and high-intensity interval training (HIIT) on vital metabolic indicators in adults with overweight and obesity.

Methods

PubMed, Cochrane, Embase, and Web of Science were searched from 1990 to February 2023. Articles were included if they described randomized controlled trials (RCTs) examining the effects of exercise training on anthropometry parameters, lipid profiles, glucose metabolism, blood pressure, and cardiorespiratory fitness in adults with overweight and obesity. Weighted mean difference with 95% CI was calculated.

Results

A total of 28 studies with 1,620 patients were included. Results revealed that AE exerts best effects on weight loss (-2.35 [-4.05, -0.64]) and body mass index (-0.9 [-1.38, -0.42]), while HIIT is the most effective in reducing waist circumference (-5.93 [10.71, -1.15]), percentage body fat (-3.93 [-5.73, -2.12]), serum triglycerides (-20.55 [-37.20, -3.91]), and fasting blood glucose (-14.31 [-22.47, -6.16]) and improving VO2 max (7.41 [4.37, 10.45]). However, no significant benefit was observed in terms of total cholesterol and blood pressure.

Conclusions

AE is the optimal exercise type for reducing body weight and BMI, while HIIT exerts the most beneficial effects on improving body composition, cardiorespiratory fitness, and metabolic abnormalities in adults with overweight and obesity.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023444322, identifier CRD42023444322.

A trend analysis of Black American women with cardiovascular disease and chronic medical conditions, sociodemographic factors from NHANES From 2011 to 2020

BACKGROUND

Significant racial and gender differences exist in the prevalence of CVD in the United States. The goal of this study is to evaluate the prevalence of CVD among Black American women, the relationship between CVD and some medical conditions, and significant sociodemographic factors.

METHODS

The researchers in this study used data from four cycles of the NHANES, carried out by the NCHS. 2011 to 2012, 2013 to 2014, 2015 to 2016, and 2017 to 2020 were the cycles that were chosen. The researchers used the survey package in the R programming language to examine the data.

RESULTS

People with CVD problems 20 years of age and older were included in the analyses. Black American women experienced a considerable prevalence of CVD from 2011 to 2020. These women were more likely to report having completed no more schooling than the ninth grade, being widowed/divorced/separated, and having undergone a hysterectomy, as well as having a history of diabetes, asthma, obesity, arthritis, and depression. Black American women with CVD had a 3.8-fold increased risk of diabetes and a 5.6-fold increased risk of arthritis.

CONCLUSION

This study shows that Black American women with CVD are more likely to have chronic illnesses such as hysterectomy, diabetes, asthma, obesity, arthritis, and depression. Black American women's cardiovascular risk profiles can be updated using the data from this study.

Body Mass Index and Outcomes of Transcatheter Aortic Valve Replacement: A Retrospective Observational Study

The influence of body mass index (BMI) on Transcatheter Aortic Valve Replacement (TAVR) outcomes has been the focus of several previous studies. In this study, we examined the relationship between BMI and various clinical outcomes following TAVR procedures. A comprehensive analysis was conducted using a large cohort of patients who underwent TAVR. In this study, we identified patients who underwent Transcatheter aortic valve replacement (TAVR) in the year 2020. Procedure Classification System (ICD-10-PCS) codes were used to identify TAVR cases. The weighted final study sample included 77319 TAVR hospitalizations. Patients were categorized into 5 groups based on their Body Mass Index (BMI. Our findings revealed that there was no significant difference in in-hospital mortality among different BMI groups when compared to patients with a normal BMI (20 to 24.9). patients with a BMI of 25 or higher demonstrated a statistically significant shorter duration of hospitalization compared to those with a normal BMI. patients with a BMI ranging between 30 and 39.9 exhibited decreased hospitalization costs when compared to patients with a normal BMI. Moreover, our study revealed a decrease in atrial fibrillation, acute heart failure and acute kidney injury complications following TAVR in patients with above-normal BMI. Despite similar in-hospital mortality across BMI groups, having a BMI of 25 or greater is associated with improved immediate outcomes following TAVR. These benefits in overweight and obese patients are consistent with findings described in recent literature. Further studies are warranted to explore the underlying mechanisms and potential implications of these associations, as well as to optimize patient selection and management strategies for TAVR procedures.

BMI category-specific waist circumference thresholds based on cardiovascular disease outcomes and all-cause mortality: Tehran lipid and glucose study (TLGS)

BACKGROUND

Waist circumference (WC), a representative of abdominal visceral fat, is strongly associated with cardiovascular disease (CVD) and its outcomes. We aimed to define body mass index (BMI)-specific WC thresholds as predictors of CVD and all-cause mortality.

METHODS

In this prospective cohort study in the context of the Tehran Lipid and Glucose Study (TLGS), a total of 3344 men and 4068 women were followed up for 18 years. Based on BMI, the participants were categorized into three groups: BMI < 25, 25 < BMI < 30, and BMI > 30. In each BMI category, sex-specific WC thresholds were estimated by the maximum value of Youden's index to predict based on incident CVD events and all-cause mortality prediction.

RESULTS

Overall 667 and 463 CVD events (the incidence rate of 3.1 to 4.5 in men and 1.1 to 2.6 in women per 1,000 person-years within BMI categories) and 438 and 302 mortalities (the incidence rate of 2.1 to 2.7 in men and 1.2 to 1.4 in women per 1,000 person-years within BMI categories) were recorded in men and women, respectively. WC thresholds in the BMI categories of < 25, 25-30, and BMI > 30 kg/m² with regard to CVD events were 82, 95, and 103 cm in men and 82, 89, and 100 cm in women, and regarding all-cause mortality, the respective values were 88, 95, and 103 cm in men and 83, 90, and 99 cm among women.

CONCLUSION

BMI-specific WC thresholds observed here can help to better identify individuals at high risk of developing CVDs.

Travel related changes in performance and physiological markers: the effects of eastward travel on female basketball players

[Purpose] Purpose of this study is to measure the changes in various physiological markers and performance criteria for women basketball players over the course of a travel heavy season. [Participants and Methods] Fifty one Division-II female basketball players and a control group of 54 females joined this study. Measurements began at the beginning of the competitive season and concluded with final measurements at the end of the competitive season. [Results] The female basketball players showed noticeable increases in resting salivary cortisol, visceral trunk fat, resting heart rate, and resting blood pressure. These athletes also showed diminishment in isokinetic force of leg muscles, particularly in knee flexion strength. Vertical jump measurements also indicated a slight diminishment. In contrast, the control group experienced none of the same changes. [Conclusion] Over the course of a grueling flight schedule in combination with a full-length basketball season, the female athletes in this study showed significant declinations in many indicators of overall health. It is concluded that resulting prolonged intermittent stress of a travel-heavy season can lead to significant changes in certain physiological markers with notable decreases in isokinetic force of leg muscle.

The Association of Body Mass Index and Waist Circumference with the Risk of Achilles Tendon Problems: A Nationwide Population-Based Longitudinal Cohort Study

Background

The purpose of this study was to evaluate the association of body mass index (BMI) and waist circumference (WC) with the risk of Achilles tendinopathy (AT) or Achilles tendon rupture (ATR), using data from a nationwide population-based cohort. We hypothesized that higher BMI and WC would be independently associated with the increased risk of AT or ATR. In addition, a higher WC may potentiate the association between BMI and the risk of Achilles tendon problems.

Methods

We used the National Health Insurance database that covers the entire South Korean population to follow up subjects who participated in the National Health Screening Program (NHSP) from January 2009 to December 2010. The NHSP data include subjects' BMI, WC, blood test results, blood pressure, and information about lifestyle. Among the subjects, those who were newly diagnosed as having AT or ATR before December 31, 2017, were selected. To examine the association of the variables with the risk of AT or ATR and determine whether the effect of higher BMI varied according to WC, multivariate Cox proportional hazards regression was used.

Results

Among a total of 16,830,532 subjects, 125,814 and 31,424 developed AT and ATR, respectively. A higher BMI showed a greater association with the increased risk of ATR than AT (adjusted hazard ratio [HR], 3.49 vs. 1.96). A higher WC was associated with the increased risk of AT (adjusted HR, 1.22), but not ATR. In a separate analysis, the association between BMI and the risk of AT was higher when subjects had higher WC as compared to those with lower WC, being most significant in individuals with both higher BMI and higher WC.

Conclusions

Higher BMI was more associated with the increased risk of ATR than AT. Moreover, a high central fat distribution played an independent and potentiating role in the development of AT. This implies the greater importance of a high central fat distribution contributing to the development of AT in obese people.

Weight Loss Versus Glycemic Control as the Primary Treatment Target in Newly Diagnosed Type 2 Diabetes: Why Choose When You Can Have Both?

Weight loss has been associated with significant improvements in glycemic control, quality of life, and comorbidities in people with type 2 diabetes. Furthermore, achieving diabetes remission can reduce the risk of microvascular complications and mitigate the burden of diabetes on healthcare systems. However, preventing weight regain is challenging in the long term. Strict glycemic control, particularly in the early stages of the disease, can reduce the subsequent risk of microvascular complications and specific macrovascular endpoints in the long run; however, its impact on cardiovascular and all-cause mortality remains controversial. New classes of antidiabetic agents, namely glucagon-like peptide 1 receptor agonists and sodium-glucose cotransporter 2 inhibitors, have been shown to reduce cardiorenal risk and induce weight loss, in addition to effectively lowering blood glucose with a minimal risk of hypoglycemia. Recently, it has been debated whether weight loss or glycemic control should be the first priority in people with a recent diagnosis of type 2 diabetes. This article aims to discuss the debate from a clinical perspective, evaluate the advantages and disadvantages of each therapeutic strategy, and assess the impact of both approaches on the future risk of diabetic complications, based on the latest evidence. Given that both goals are equally important, the authors suggest that merging the two strategies, with the early and aggressive use of combination therapies consisting of glucagon-like peptide 1 receptor agonists and sodium-glucose cotransporter 2 inhibitors, will confer maximum benefits in terms of weight loss and glycemic control, and will reduce the future risk of complications from diabetes. A personalized approach that takes into account specific patient characteristics, including age, sex, race, frailty, and cognitive status, among others, can lead to more effective diabetes care.

Influence of Waist Circumference Measurement Site on Visceral Fat and Metabolic Risk in Youth

Although the rate of childhood obesity seems to have plateaued in recent years, the prevalence of obesity among children and adolescents remains high. Childhood obesity is a major public health concern as overweight and obese youth suffer from many co-morbid conditions once considered exclusive to adults. It is now well demonstrated that abdominal obesity as measured by waist circumference (WC) is an independent risk factor for cardiovascular disease and metabolic dysfunction in youth. Despite the strong associations between WC and cardiometabolic risk factors, there is no consensus regarding the optimal WC measurement sites to assess abdominal obesity and obesity-related health risk in children and adolescents. Currently, the WC measurement site that provides the best reflections of visceral fat and the best correlations with cardiometabolic risk factors is unclear. The purpose of this review is to explore whether WC measurement sites influence the relationships between WC, visceral fat, and cardiometabolic risk factors in children and adolescents.

Association of anthropometric indices with the development of multimorbidity in middle-aged and older adults: A retrospective cohort study

BACKGROUND

Previous studies have explored the relationship between body mass index (BMI) and multimorbidity. However, the relationship between other obesity indicators and their dynamic changes and multimorbidity has not been systematically estimated. Therefore, we aimed to investigate the association of BMI and other obesity indicators, including waist circumference (WC), waist-to-height ratio (WHtR), waist divided by height0.5 (WHT.5R), and body roundness index (BRI) and their changes and the risk of multimorbidity in middle-aged and older adults through a retrospective cohort study.

METHODS

Data collected from annual health examination dataset in the Jinshui during 2017 and 2021. Cox regression models were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) to evaluate the effect of baseline and dynamic changes in the anthropometric indices on the risk of multimorbidity.

RESULTS

A total of 75,028 individuals were included in the study, and 5,886 participants developed multimorbidity during the follow-up. Multivariate Cox regression analysis revealed a progressive increase in the risk of multimorbidity with increasing anthropometric indicators (BMI, WC, WHtR, WHT.5R, and BRI) (all P<0.001). Regardless of general obesity status at baseline, increased WC was associated with a high risk of multimorbidity. Compared to the subjects with baseline BMI<24 kg/m2 and WC<90 (men)/80 (women), the HRs (95% CI) of the baseline BMI<24 kg/m2 and WC≥90 (men)/80 (women) group and BMI≥24 kg/m2 and WC≥90 (men)/80 (women) group were 1.31 (1.08, 1.61) and 1.82 (1.68, 1.97), respectively. In addition, the dynamics of WC could reflect the risk of multimorbidity. When subjects with baseline WC<90 (men)/80 (women) progressed to WC≥90 (men)/80 (women) during follow-up, the risk of multimorbidity significantly increased (HR = 1.78; 95% CI, 1.64, 1.95), while the risk of multimorbidity tended to decrease when people with abnormal WC at baseline reversed to normal at follow-up (HR = 1.40; 95% CI, 1.26, 1.54) compared to those who still exhibited abnormal WC at follow-up (HR = 2.00; 95% CI, 1.82, 2.18).

CONCLUSIONS

Central obesity is an independent and alterable risk factor for the occurrence of multimorbidity in middle-aged and elderly populations. In addition to the clinical measurement of BMI, the measurement of the central obesity index WC may provide additional benefits for the identification of multimorbidity in the Chinese middle-aged and elderly populations.

Multidisciplinary Progress in Obesity Research

Obesity is a chronic disease that endangers human health. In recent years, the phenomenon of obesity has become more and more common, and it has become a global epidemic. Obesity is closely associated with many adverse metabolic changes and diseases, such as insulin resistance, type 2 diabetes mellitus, coronary heart disease, nervous system diseases and some malignant tumors, which have caused a huge burden on the country's medical finance. In most countries of the world, the incidence of cancer caused by obesity is increasing year on year. Diabetes associated with obesity can lead to secondary neuropathy. How to treat obesity and its secondary diseases has become an urgent problem for patients, doctors and society. This article will summarize the multidisciplinary research on obesity and its complications.

Elevated levels of body mass index and waist circumference, but not high variability, are associated with an increased risk of atrial fibrillation

BACKGROUND

Although obesity has been associated with risk of atrial fibrillation (AF), the associations of variability of obesity measures with AF risk are uncertain, and longitudinal studies among Chinese population are still lacking. We aimed to evaluate the impacts of obesity and variability of body mass index (BMI) and waist circumference (WC) on the risk of atrial fibrillation (AF) in a large Chinese cohort study.

METHODS

A total of 44,135 participants of the Kailuan Study who were free of cancer and cardiovascular disease and underwent three consecutive surveys from 2006 to 2010 were followed for incident AF until 2020. Average BMI and WC over time and variability were calculated. Cox proportional hazards regression models were used to assess hazard ratios (HRs) and 95% confidence intervals (CIs) for the associations of obesity and variability in BMI and WC with AF risk.

RESULTS

During a mean follow-up of 9.68 years, there were 410 cases of incident AF. In multivariable-adjusted models, compared with normal BMI/WC, individuals with general obesity and abdominal obesity had increased risk of AF, with corresponding HRs of 1.73 (95% CI: 1.31-2.30) and 1.38 (95% CI: 1.11-1.60), respectively. The short-term elevation in AF risk persisted for the obese even after adjustment for updated biologic intermediaries and weight. Variability in BMI and WC were not associated with the risk of AF. The restricted cubic spline models indicated significant linear relationships between levels of WC and BMI and risk of AF.

CONCLUSIONS

Elevated levels of BMI and WC were associated with an increased risk of AF, whereas variability in BMI and WC were not. Therefore, achieving optimal levels of BMI and WC could be valuable in AF prevention.

Effects of exercise training on obesity-related parameters in people with intellectual disabilities: systematic review and meta-analysis

BACKGROUND

Efforts to synthesise existing knowledge concerning the effects of exercise interventions on obesity (i.e. changes in body weight and composition) have been made, but scientific evidence in this matter is still limited. This systematic review and meta-analysis aims to identify and critically analyse the best available evidence regarding the use of physical exercise as a strategy to attenuate obesity through its effects on adiposity-related anthropometric parameters in people with intellectual disability (ID).

METHODS

Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, a literature search was performed using PubMed, Scopus, SPORTDiscus, CINAHL and the Cochrane Library through specific keywords up to July 2020. The search adhered to the population, intervention, comparison and outcome strategy. Randomised controlled trials addressing the effects of the exercise intervention on adiposity-related anthropometric parameters (body mass index, waist circumference, waist-hip ratio, fat percentage or body weight) in children, adolescents and adults with ID were included. The methodological quality of the studies found was evaluated through the PEDro scale.

RESULTS

A total of nine investigations with children and/or adolescents (10-19 years) and 10 investigations with adults (18-70 years) were selected, mostly experiencing mild and moderate ID. Methodological quality was fair in 13 of these publications, good in five and excellent in one. Seventeen trials reported comparable baseline and post-intervention data for the intervention and control groups and were included in the meta-analysis. In nine studies, the intervention group performed a cardiovascular training programme. Five papers described a combined training programme. Two trials executed whole-body vibration training programmes, and one publication proposed balance training as the primary intervention. According to the meta-analysis results, the reviewed studies proposed exercise modalities that, in comparison with the activities performed by the participants' in the respective control groups, did not have a greater impact on the variables assessed.

CONCLUSIONS

While physical exercise can contribute to adiposity-related anthropometric parameters in people with mild and moderate ID, these findings show that exercise alone is not sufficient to manage obesity in this population. Multicomponent interventions appear to be the best choice when they incorporate dietary deficit, physical activity increase and behaviour change strategies. Finding the most effective modality of physical exercise can only aid weight loss interventions. Future research would benefit from comparing the effects of different exercise modalities within the framework of a multicomponent weight management intervention.

The role of body height as a co-factor of excess weight in Switzerland

Object

Excess weight (Body Mass Index [BMI] ≥25.0 kg/m²) is a major health issue worldwide, including in Switzerland. For high‐income countries, little attention has been paid to body height in context of excess weight. The aim of this study is to assess the importance of body height as a co‐factor for excess weight in multiple large nationwide data sets.

Data and methods

In this comparative study, we included the largest nationwide and population‐based studies in the fields of public health, nutrition and economics for Switzerland, as well as data of the medical examination during conscription for the Swiss Armed Forces, which contained information on BMI and, if possible, waist‐to‐height‐ratio (WHtR) and waist‐to‐hip‐ratio (WHR).

Results

The multinomial logistic regressions show that the probability of belonging to the excess weight category (BMI ≥25.0 kg/m²) decreased with increasing height in both sexes inall contemporary data sets. This negative association was shown to be constant, only among conscripts measured in the 1870s the association was positive, when increasing height was associated with a higher BMI. The negative association not only emerge in BMI, but also in WHtR and WHR.

Conclusion

Our results emphasize the importance of body height as a co‐factor of excess weight, suggesting a clear negative association between height and BMI, WHtR and WHR. Evidence indicates that both early‐life environmental exposures and alleles associated with height may contribute to these associations. This knowledge could serve as further starting points for prevention programs in the field of public health.

Waist circumference and mortality or cardiovascular events in a general Korean population

Background

Obesity is associated with cardiovascular diseases and is a risk factor for all-cause mortality. Until now, the associations between abdominal obesity and mortality or cardiovascular disease (CVD) incidence have not been conclusive. We aimed to evaluate the associations between waist circumference (WC) and mortality or CVD incidence in a general Korean population.

Methods

We analyzed a total of 204,068 adults older than 40 years of age who had undergone a national health examination at least once from 2009 to 2018 in the Korean National Health Insurance Service Cohort. WC was divided into five categories (< 80, 80–84.9, 85–89.9, 90–94.9, ≥ 95 cm). Hazard ratios for death and CVD incidence were calculated using Cox proportional hazards models.

Results

In men, WC and overall mortality showed a reverse J-shaped association. In women, the association between WC and overall mortality was not significant. For both men and women, WC was not associated with the risk of cardiovascular mortality. Contrary to the mortality trend, CVD incidence was positively associated with WC in both men and women, and the risk of the CVD incidence was the lowest in subjects with a WC < 80 cm.

Conclusions

WC exhibited a significant J-shaped association with overall mortality in men, where subjects who had central obesity showed a lower rate of mortality than those in the lowest or highest WC group. The risk of incident CVD showed a positive association with central obesity, where the lowest risk was observed for subjects in the lowest WC group in a general Korean population.

Maternal pregnancy weight or gestational weight gain and offspring's blood pressure: A systematic review

AIMS

An increasing number of studies suggest that maternal weight parameters in pregnancy are associated with offspring's blood pressure (BP). The aim of this systematic review - following the updated Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) Statement - was to assess and judge the evidence for an association between maternal pregnancy weight/body mass index (BMI) or gestational weight gain (GWG) with offspring's BP in later life.

DATA SYNTHESIS

MEDLINE, EMBASE, Cochrane Library, CINAHL and Web of Science were searched without limits. Risk of bias was assessed using the "US National Heart, Lung and Blood Institute"-tool, and an evidence grade was allocated following the "World Cancer Research Fund" criteria. Of 7,124 publications retrieved, 16 studies (all cohort studies) were included in the systematic review. Overall data from 52,606 participants (0 years [newborns] to 32 years) were enclosed. Association between maternal pregnancy BMI and offspring's BP were analyzed in 2 (both "good-quality" rated) studies, without consistent results. GWG and offspring's BP was analyzed in 14 studies (2 "good-quality", 9 "fair-quality", 3 "poor-quality" rated). Of these, 3 "fair-quality" studies described significant positive results for systolic BP and significant results, but partly with varying directions of effect estimates for diastolic BP. Mean arterial pressure (MAP) was analyzed in 1 "poor-quality" congress paper. Overall, based on the small number of "good-quality"-rated studies and the inconsistency of effect direction, no firm conclusion can be drawn.

CONCLUSION

Evidence for an association of maternal pregnancy weight determinants with offspring's BP was overall graded as "limited - no conclusion".

The Effect of Exercise on Cardiometabolic Risk Factors in Women with Polycystic Ovary Syndrome: A Systematic Review and Meta-Analysis

Background: Polycystic Ovary Syndrome (PCOS), a common endocrine disorder in women of reproductive age, increases the risk for cardiometabolic morbidity. While regular exercise is effective in reducing cardiometabolic risk, women with PCOS may experience condition-specific barriers to exercise thereby limiting its efficacy. Aim: To determine the effect of exercise on cardiometabolic risk factors in women with PCOS. Methods: Five databases (Cochrane, EMBASE, Medline, Scopus and SPORTDiscus) were searched up to December of 2021. Eligible studies included: a randomised controlled design; participants with a diagnosis of PCOS; aerobic and/or resistance exercise intervention lasting ≥4 weeks; cardiometabolic outcomes. Meta-analyses were performed to determine the effect of exercise versus non-exercising control on cardiometabolic outcomes. Results: Of the 4517 studies screened, 18 studies were analysed involving 593 participants. When compared with control, exercise significantly improved cardiorespiratory fitness (weighted mean difference {WMD} = 4.00 mL/kg/min, 95% CI: 2.61 to 5.40, p < 0.001) and waist circumference (WMD = −1.48 cm, 95% CI: −2.35 to −0.62, p = 0.001). Systolic blood pressure, fasting blood glucose, insulin resistance, and lipid profiles remained unchanged. Conclusions: Regular exercise may improve cardiorespiratory fitness and waist circumference in women with PCOS. Further large-scale studies are required to determine whether exercise interventions improve various biochemical and anthropometric parameters in women with PCOS and more severe cardiometabolic abnormalities.

Mendelian randomization analysis of the causal impact of body mass index and waist-hip ratio on rates of hospital admission

We analyze how measures of adiposity - body mass index (BMI) and waist hip ratio (WHR) - causally influence rates of hospital admission. Conventional analyses of this relationship are susceptible to omitted variable bias from variables that jointly influence both hospital admission and adipose status. We implement a novel quasi-Poisson instrumental variable model in a Mendelian randomization framework, identifying causal effects from random perturbations to germline genetic variation. We estimate the individual and joint effects of BMI, WHR, and WHR adjusted for BMI. We also implement multivariable instrumental variable methods in which the causal effect of one exposure is estimated conditionally on the causal effect of another exposure. Data on 310,471 participants and over 550,000 inpatient admissions in the UK Biobank were used to perform one-sample and two-sample Mendelian randomization analyses. The results supported a causal role of adiposity on hospital admissions, with consistency across all estimates and sensitivity analyses. Point estimates were generally larger than estimates from comparable observational specifications. We observed an attenuation of the BMI effect when adjusting for WHR in the multivariable Mendelian randomization analyses, suggesting that an adverse fat distribution, rather than a higher BMI itself, may drive the relationship between adiposity and risk of hospital admission.

Differences in the choroid plexus volume and microstructure are associated with body adiposity

The choroid plexus (CP) is a cerebral structure located in the ventricles that functions in producing most of the brain's cerebrospinal fluid (CSF) and transporting proteins and immune cells. Alterations in CP structure and function has been implicated in several pathologies including aging, multiple sclerosis, Alzheimer's disease, and stroke. However, identification of changes in the CP remains poorly characterized in obesity, one of the main risk factors of neurodegeneration, including in the absence of frank central nervous system alterations. Our goal here was to characterize the association between obesity, measured by the body mass index (BMI) or waist circumference (WC) metrics, and CP microstructure and volume, assessed using advanced magnetic resonance imaging (MRI) methodology. This cross-sectional study was performed in the clinical unit of the National Institute on Aging and included a participant population of 123 cognitively unimpaired individuals spanning the age range of 22 - 94 years. Automated segmentation methods from FreeSurfer were used to identify the CP structure. Our analysis included volumetric measurements, quantitative relaxometry measures (T ₁ and T ₂), and the diffusion tensor imaging (DTI) measure of mean diffusivity (MD). Strong positive associations were observed between WC and all MRI metrics, as well as CP volume. When comparing groups based on the established cutoff point by the National Institutes of Health for WC, a modest difference in MD and a significant difference in T ₁ values were observed between obese and lean individuals. We also found differences in T1 and MD between obese and overweight individuals as defined using the BMI cutoff. We conjecture that these observations in CP volume and microstructure are due to obesity-induced inflammation, diet, or, very likely, dysregulations in leptin binding and transport. These findings demonstrate that obesity is strongly associated with a decline in CP microstructural integrity. We expect that this work will lay the foundation for further investigations on obesity-induced alterations in CP structure and function.

Waist-to-height ratio has a stronger association with cardiovascular risks than waist circumference, waist-hip ratio and body mass index in type 2 diabetes

AIMS

To compare the associations between four anthropometric indices including waist-to-height ratio (WHtR), waist circumference (WC), waist-hip-ratio (WHR) and body mass index (BMI) and cardio-cerebrovascular events (CCBVEs) in Chinese T2DM patients.

METHODS

The associations of four anthropometric measures with CCBVEs and metabolic syndrome (MetS) were compared by multiple regression model in 3108 T2DM patients. CCBVEs was defined as a history of myocardial infarction, angina, angioplasty, coronary artery bypass surgery, transient ischemic attack, ischemic or hemorrhagic stroke.

RESULTS

After controlling for age, sex and diabetes duration, the prevalence of CCBVEs and MetS significantly increased across the WHtR, WC, WHR and BMI quartiles in T2DM patients, respectively. However, when controlling for these four anthropometric measurements together, although four anthropometric measures were closely associated with MetS prevalence, only WHtR quartile was significantly associated with CCBVEs prevalence (6.5%, 13.8%, 16.9% and 21.3%, p < 0.001 for trend). After adjusting for multiple confounders including four anthropometric parameters, a regression analysis revealed that only WHtR was independently and positively associated with the presence of CCBVEs (p = 0.029).

CONCLUSIONS

Compared with WC, WHR and BMI, WHtR have a stronger association with CCBVEs in T2DM subjects. WHtR maybe a better indicator than other anthropometric measurements for evaluating cardiovascular risks in T2DM.

Influence of Obesity on Heart Rate Variability in Nurses with Age and Shift Type as Moderators

Obesity is a risk factor of cardiovascular disease-related mortality and may be associated with changes in the autonomic nerve activity. Nurses working shifts and caring for patients are under great mental and physical pressure, and research has proven that these can negatively affect the body. The objective of this study was to examine the influence of obesity in nurses on their heart rate variability (HRV) and determine whether age or shift type moderates this influence. A questionnaire survey and HRV measurements were conducted on nurses at a hospital in Taiwan during a routine employee health checkup. HRV analysis was conducted using a noninvasive HRV monitor for five minutes. A total of 242 nurses with a mean age of 28.98 ± 6.56 years were enrolled in this study. An overly large waist circumference (WC) had a negative impact on high frequency (HF), low frequency (LF), and standard deviation of normal-to-normal interval (SDNN), while an overly high body mass index (BMI) had a negative impact on very low frequency (VLF) and SDNN. The interaction term “overly large WC × age” had a negative impact on HF (β = −0.21, p = 0.010) and LF (β = −0.18, p = 0.030), whereas the interaction term “overly high BMI×age” had a negative impact on HF (β = −0.27, p = 0.001), LF (β = −0.19, p = 0.023), and VLF (β = −0.17, p = 0.045). The interaction terms “overly large WC × shift type” and “overly high BMI × shift type” did not influence any HRV parameters. As age increased, so did the degree to which the HF and LF of nurses with an overly large WC were lower than normal, and so did the degree to which the HF, LF, and VLF of nurses with an overly high BMI were lower than normal.

Dynapenic abdominal obesity and the effect on long-term gait speed and falls in older adults

BACKGROUND

Although both dynapenia and abdominal obesity have negative impact on physical function and health, few prospective studies evaluate the association of dynapenic abdominal obesity (D/AO) with gait speed and falls. Our aim was to examine the combined effect of low muscle strength and abdominal obesity on long-term gait speed and falls in older adults.

METHODS

We used longitudinal data from the English Longitudinal Study of Ageing (ELSA), including 4987 individuals aged 60 years and over. Grip strength and waist circumference were measured at baseline. Gait speed and fall events (falls, recurrent falls, and fall-related injury) were evaluated during a 14-year follow-up. The study population were divided into nondynapenic nonabdominal obesity (ND/NAO), nondynapenic abdominal obesity (ND/AO), dynapenic nonabdominal obesity (D/NAO), and D/AO, according to the sex-specific grip strength (<16 kg for women and <26 kg for men) and waist circumference (>88 cm for women and >102 cm for men). We used generalized estimating equation (GEE) model with gait speed as the outcome and cox proportional hazards models with fall events as the outcome.

RESULTS

GEE model showed that gait speed decreased during the 14-year follow-up in all groups (all P_time < 0.001). Participants with ND/AO, D/NAO, and D/AO at baseline exhibited a worse gait speed than those with ND/NAO (all P_group < 0.001). No significant difference in the rate of gait speed decline between four groups was found (P_group×time = 0.062). Cox regression analysis showed that D/NAO and D/AO highly predicted falls, and the hazard ratio (HR) was 1.181 (95% CI: 1.002, 1.392) for D/NAO and 1.195 (95% CI: 1.006, 1.421) for D/AO. D/AO was the unique condition associated with recurrent falls and fall-related injury, and the HRs were 1.276 (95% CI: 1.018, 1.599) and 1.348 (95% CI: 1.066, 1.704), respectively.

CONCLUSION

Dynapenia abdominal obesity, determined by low grip strength and high waist circumference, exhibits worse gait speed and increases the risk of fall events in older adults. Effort to maintain the mobility should focus on improving muscle strength and reducing excess body fat.

Supplemental nutrition assistance program 2009 expansion and cardiometabolic markers among low-income adults

A 2009 Supplemental Nutrition Assistance Program (SNAP) policy change that expanded eligibility and increased benefit amounts has been associated with reduced food insecurity. This study tests the hypothesis that the SNAP policy change corresponds with improved stress- and nutrition-sensitive cardiometabolic markers. This study included non-pregnant participants aged 18-59 with annual family incomes ≤185% of the federal poverty guideline from the repeated cross-sectional NHANES study. Those living in SNAP eligible households (income ≤130% of the poverty guideline) were compared to those who were likely non-eligible (income 131%-≤185%). Difference-in-differences analyses compared hemoglobin A1c (%), CRP (mg/dL), total cholesterol (mg/dL), LDL (mg/dL) and waist circumference (cm) across groups before (2007-2008) and after (2009-2010) the SNAP policy change. Sampling weights were applied. Adjusting for demographic, socioeconomic, household and health factors, there were statistically significant difference-in-differences estimates for hemoglobin A1c (p = 0.003, n = 3723) and total cholesterol (p = 0.028, n = 3710). SNAP eligible adults had no difference in hemoglobin A1c after the policy change and, among those less than 40 years of age, 5 mg/dL lower total cholesterol levels whereas likely non-SNAP eligible adults had 0.14% higher hemoglobin A1c and no difference in total cholesterol after the policy change. The 2009 SNAP expansion was associated with improved nutrition-sensitive cardiometabolic markers in SNAP-eligible adults. This study found less of an upward trend in hemoglobin A1c levels for young and middle aged adults and decreased total cholesterol for young adults. These results highlight the potential role of SNAP to prevent costly chronic conditions among low-income U.S. adults.

Waist-to-height ratio, waist circumference, body mass index, waist divided by height0.5 and the risk of cardiometabolic multimorbidity: A national longitudinal cohort study

BACKGROUND AND AIMS

Cardiometabolic multimorbidity (CM) is an increasing public health burden. This study aimed to evaluate the association of waist-to-height ratio (WHtR), waist circumference (WC), waist divided by height^0.5 (WHT.5R) and body mass index (BMI) with the risk of CM.

METHODS AND RESULTS

We used data from the China Health and Retirement Longitudinal Study (CHARLS). A total of 10,521 participants aged 45 years and over were recruited, including 8807 individuals with 0 cardiometabolic diseases at baseline (stage I) and 1714 individuals with 1 cardiometabolic disease at baseline (stage II). CM was defined as self-reporting of two or more of the following conditions: stroke, diabetes and heart disease. Logistic regression was conducted to estimate the odds ratios (ORs) and 95% confidence intervals (CIs). The net reclassification index (NRI) and integrated discrimination improvement (IDI) were used to evaluate the incremental predictive value beyond conventional factors. In stage I, an increased risk of CM was observed among participants with WHtR ≥0.5 (OR: 1.76, 95% CI: 1.05-2.97), WC ≥ 90 cm (men) + WC ≥ 80 cm (women) (OR: 2.06, 95% CI: 1.29-3.27), WHT.5R ≥ 6.54 cm^0.5 (OR: 1.81, 95% CI: 1.16-2.83) or BMI ≥24 kg/m² (OR: 1.48, 95% CI: 0.98-2.24). Furthermore, the NRI and IDI of WHtR, WC and WHT.5R were all higher than those of BMI. In stage II, the adjusted ORs (95% CIs) of WHtR, WC, WHT.5R and BMI were 2.04 (1.24-3.35), 1.89 (1.29-2.77), 1.86 (1.24-2.78) and 1.47 (1.06-2.04), respectively. In addition, WC exhibited the highest NRI and IDI.

CONCLUSION

WHtR, WC, WHT.5R and BMI are independent predictors of CM in the middle-aged and older Chinese population. WHtR, WC and WHT.5R show better abilities in predicting CM than BMI.

Change in waist circumference over 2 years and the odds of left ventricular hypertrophy among Chinese children

BACKGROUND AND AIMS

High waist circumference (WC) is associated with left ventricular mass index (LVMI) in childhood. However, no studies have assessed the association between WC change and left ventricular hypertrophy (LVH) in childhood. This study aimed to investigate the association between change in WC status over 2 years on LVH among Chinese children.

METHODS AND RESULTS

Data were from a population-based prospective cohort study in China. Children without LVH at baseline (n = 1067) were assigned to four WC status change groups (persistent normal WC, WC loss, WC gain, and persistent abdominal obesity). Over a 2-year follow-up, 103 (out of 1067) children had LVH. LVMI levels were the highest among the persistent abdominal obesity group (31.5 ± 3.8 g/m ^2.7), lower in the WC gain group (31.0 ± 3.6 g/m ^2.7) and the WC loss group (29.8 ± 3.7 g/m ^2.7), and lowest in the persistent normal WC group (29.1 ± 3.7 g/m ^2.7). Compared with children in the persistent normal WC group, the odds of LVH was highest in the persistent abdominal obesity group [odds ratio (OR) = 3.57, 95% confidence interval (CI): 2.18-5.83], followed by the WC gain group (OR = 2.85, 95% CI: 1.50-5.41). In contrast, the odds of LVH was not increased in the WC loss group (OR = 0.93, 95% CI: 0.21-4.07).

CONCLUSION

Although these findings highlight the importance of maintaining normal WC in childhood to reduce the odds of developing LVH, our data suggest the increased odds associated with abdominal obesity can be reversed by WC loss.

The Direct Effect of Body Mass Index on Cardiovascular Outcomes among Participants Without Central Obesity by Targeted Maximum Likelihood Estimation

BACKGROUND

Body mass index (BMI) is the most commonly used index to categorize a person as obese or non-obese, which is subject to important limitations.

OBJECTIVE

To evaluate the direct effect of BMI on cardiovascular outcomes among participants without central obesity.

METHODS

This analysis included 14,983 males and females aged 45-75 years from the Atherosclerosis Risk in Communities Study (ARIC). BMI was measured as general obesity, and waist circumference (WC), waist-to-hip ratio (WHR) and hip circumference as central obesity. Targeted maximum likelihood estimation (TMLE) was used to estimate the total effects (TEs) and the controlled direct effects (CDEs). The proportion of TE that would be eliminated if all participants were non-obese regarding central obesity was computed using the proportion eliminated (PE) index. P <0.05 was considered statistically significant. Analyses were performed in the TMLE R package.

RESULTS

The risk of cardiovascular outcomes attributed to BMI was significantly reversed by eliminating WHR obesity (p<0.001). The proportion eliminated of BMI effects was more tangible for non-obese participants regarding WC (PE=127%; 95%CI (126,128)) and WHR (PE=97%; 95%CI (96,98)) for coronary heart disease (CHD), and WHR (PE=92%; 95%CI (91,94)) for stroke, respectively. With respect to sex, the proportion eliminated of BMI effects was more tangible for non-obese participants regarding WHR (PE=428%; 95%CI (408,439)) for CHD in males, and WC (PE=99%; 95%CI (89,111)) for stroke in females, respectively.

CONCLUSION

These results indicate different potential effects of eliminating central obesity on the association between BMI and cardiovascular outcomes for males and females. (Arq Bras Cardiol. 2021; 116(5):879-886).

Joint Associations Between Body Mass Index and Waist Circumference With Atrial Fibrillation in Men and Women

Background Associations between adiposity and atrial fibrillation (AF) might differ between sexes. We aimed to determine precise estimates of the risk of AF by body mass index (BMI) and waist circumference (WC) in men and women. Methods and Results Between 2008 and 2013, over 3.2 million adults attended commercial screening clinics. Participants completed health questionnaires and underwent physical examination along with cardiovascular investigations, including an ECG. We excluded those with cardiovascular and cardiac disease. We used multivariable logistic regression and determined joint associations of BMI and WC and the risk of AF in men and women by comparing likelihood ratio χ2 statistics. Among 2.1 million included participants 12 067 (0.6%) had AF. A positive association between BMI per 5 kg/m2 increment and AF was observed, with an odds ratio of 1.65 (95% CI, 1.57-1.73) for men and 1.36 (95% CI, 1.30-1.42) for women among those with a BMI above 20 kg/m2. We found a positive association between AF and WC per 10 cm increment, with an odds ratio of 1.47 (95% CI, 1.36-1.60) for men and 1.37 (95% CI, 1.26-1.49) for women. Improvement of likelihood ratio χ2 was equal after adding BMI and WC to models with all participants. In men, WC showed stronger improvement of likelihood ratio χ2 than BMI (30% versus 23%). In women, BMI showed stronger improvement of likelihood ratio χ2 than WC (23% versus 12%). Conclusions We found a positive association between BMI (above 20 kg/m2) and AF and between WC and AF in both men and women. BMI seems a more informative measure about risk of AF in women and WC seems more informative in men.

Evidence of association between obesity and lower cerebral myelin content in cognitively unimpaired adults

BACKGROUND

Myelin loss is a central feature of several neurodegenerative diseases, including Alzheimer's disease (AD). In animal studies, a link has been established between obesity and impairment of oligodendrocyte maturation, the cells that produce and maintain myelin. Although clinical magnetic resonance imaging (MRI) studies have revealed microstructural alterations of cerebral white matter tissue in subjects with obesity, no specific myelin vs. obesity correlation studies have been performed in humans using a direct myelin content metric.

OBJECTIVES

To assess the association between obesity and myelin integrity in cerebral white matter using advanced MRI methodology for myelin content imaging.

METHODS

Studies were performed in the clinical unit of the National Institute on Aging on a cohort of 119 cognitively unimpaired adults. Using advanced MRI methodology, we measured whole-brain myelin water fraction (MWF), a marker of myelin content. Automated brain mapping algorithms and statistical models were used to evaluate the relationships between MWF and obesity, measured using the body mass index (BMI) or waist circumference (WC), in various white matter brain regions.

RESULTS

MWF was negatively associated with BMI or WC in all brain regions evaluated. These associations, adjusted for sex, ethnicity, and age, were statistically significant in most brain regions examined (p < 0.05), with higher BMI or WC corresponding to lower myelin content. Finally, in agreement with previous work, MWF exhibited a quadratic, inverted U-shaped, association with age; this is attributed to the process of myelination from youth through middle age, followed by demyelination afterward.

CONCLUSIONS

These findings suggest that obesity was significantly associated with white matter integrity, and in particular myelin content. We expect that this work will lay the foundation for further investigations to clarify the nature of myelin damage in neurodegeneration, including AD, and the effect of lifestyle factors such as diet and physical activity on myelination.

Effect modification of general and central obesity by sex and age on cardiovascular outcomes: Targeted maximum likelihood estimation in the atherosclerosis risk in communities study

BACKGROUND AND AIMS

To elucidate the effect modification of general and central obesity by sex and age on the risk of cardiovascular events.

METHODS

The analysis included 14,983 males and females aged 45-75 years from the Atherosclerosis Risk in Communities study. Obesity was defined with body mass index (BMI), waist-to-hip ratio (WHR) and body shape index (BSI) which categorized the participants as obese and non-obese. Targeted maximum likelihood estimation was used to estimate the risk ratio (RR) with the tmle package in R software.

RESULTS

After adjustment, the strongest effect of BMI on CHD was in females (RR (95%CI): 1.26 (1.11, 1.42)) and in age>54 (RR (95%CI): 1.16 (1.06, 1.27)) and for HF it was in age>54 (RR (95%CI): 1.18 (1.10, 1.26)) and in females (RR (95%CI): 1.17 (1.08, 1.28)). Regarding central obesity, WHR (RR (95%CI): 1.19 (1.05, 1.34)) had the strongest effects on CHD for males and BSI (RR (95%CI): 1.140 (1.02, 1.26)) for age ≤ 54, and for HF the WHR (RR (95%CI): 1.22 (1.10, 1.36)) and BSI (RR (95%CI): 1.18 (1.07, 1.30)) had the strongest effects for age≤54, respectively.

CONCLUSION

Among males and age≤54, WHR index was associated with a higher risk of CHD and HF while BMI was so for females and age>54.

Quantification of abdominal fat from computed tomography using deep learning and its association with electronic health records in an academic biobank

OBJECTIVE

The objective was to develop a fully automated algorithm for abdominal fat segmentation and to deploy this method at scale in an academic biobank.

MATERIALS AND METHODS

We built a fully automated image curation and labeling technique using deep learning and distributive computing to identify subcutaneous and visceral abdominal fat compartments from 52,844 computed tomography scans in 13,502 patients in the Penn Medicine Biobank (PMBB). A classification network identified the inferior and superior borders of the abdomen, and a segmentation network differentiated visceral and subcutaneous fat. Following technical evaluation of our method, we conducted studies to validate known relationships with visceral and subcutaneous fat.

RESULTS

When compared with 100 manually annotated cases, the classification network was on average within one 5-mm slice for both the superior (0.4 ± 1.1 slice) and inferior (0.4 ± 0.6 slice) borders. The segmentation network also demonstrated excellent performance with intraclass correlation coefficients of 1.00 (P < 2 × 10-16) for subcutaneous and 1.00 (P < 2 × 10-16) for visceral fat on 100 testing cases. We performed integrative analyses of abdominal fat with the phenome extracted from the electronic health record and found highly significant associations with diabetes mellitus, hypertension, and renal failure, among other phenotypes.

CONCLUSIONS

This work presents a fully automated and highly accurate method for the quantification of abdominal fat that can be applied to routine clinical imaging studies to fuel translational scientific discovery.

What exercise prescription is optimal to improve body composition and cardiorespiratory fitness in adults living with obesity? A network meta-analysis

Current international guidelines recommend people living with obesity should be prescribed a minimum of 300 min of moderately intense activity per week for weight loss. However, the most efficacious exercise prescription to improve anthropometry, cardiorespiratory fitness (CRF) and metabolic health in this population remains unknown. Thus, this network meta-analysis was conducted to assess and rank comparative efficacy of different exercise interventions on anthropometry, CRF and other metabolic risk factors. Five electronic databases were searched for randomized controlled trials (RCTs) that compared different exercise modalities to improve anthropometry, CRF and/or metabolic health in adults living with obesity. RCTs were evaluated using the Cochrane risk of bias tool. A random effects network meta-analysis was performed within a frequentist framework. Of the 6663 articles retrieved, 45 studies with a total 3566 participants were included. Results reveal that while any type of exercise intervention is more effective than control, weight loss induced is modest. Interventions that combine high-intensity aerobic and high-load resistance training exert beneficial effects that are superior to any other exercise modality at decreasing abdominal adiposity, improving lean body mass and increasing CRF. Clinicians should consider this evidence when prescribing exercise for adults living with obesity, to ensure optimal effectiveness.

Physical Activity and Mortality Across Levels of Adiposity: A Prospective Cohort Study From the UK Biobank

OBJECTIVE

To examine the combined and stratified associations of physical activity and adiposity measures, modelled as body mass index (BMI), abdominal adiposity (waist circumference), and body fat percentage (BF) with all-cause mortality.

PATIENTS AND METHODS

Using the UK Biobank cohort, we extracted quintiles of self-reported weekly physical activity. Categories of measured BMI, waist circumference, and BF were generated. Joint associations between physical activity-adiposity categories and mortality were examined using Cox proportional hazards models adjusted for demographic, behavioral, and clinical covariates. Physical activity-mortality associations were also examined within adiposity strata. Participants were followed from baseline (2006 to 2010) through January 31, 2018.

RESULTS

A total of 295,917 participants (median follow-up, 8.9 years, during which 6684 deaths occurred) were included. High physical activity was associated with lower risk of premature mortality in all strata of adiposity except for those with BMI ≥35 kg/m². Highest risk (HR, 1.54; 95% CI; 1.33 to 1.79) was observed in individuals with low physical activity and high BF as compared with the high physical activity-low BF referent. High physical activity attenuated the risk of high adiposity when using BF (HR, 1.24; 95% CI; 1.04 to 1.49), but the association was weaker with BMI (HR, 1.45; 95% CI; 1.21 to 1.73). Physical activity also attenuated the association between mortality and high waist circumference.

CONCLUSION

Low physical activity and adiposity were both associated with a higher risk of premature mortality, but high physical activity attenuated the increased risk with adiposity irrespective of adiposity metric, except in those with a BMI ≥35 kg/m².

Cumulative Cardiovascular Disease Risk and Triglycerides Differentially Relate to Subdomains of Executive Function in Bipolar Disorder; preliminary findings

OBJECTIVES

Cardiovascular disease is disproportionally prevalent in bipolar disorder (BD) and has been linked to cognition in preliminary studies. Herein we evaluate the association between known risk factors for cardiovascular disease and executive function in BD patients compared to healthy controls.

METHODS

In a sample of n=57 individuals (n=23 BD, n=34 controls) we assessed two subdomains of executive function; cognitive flexibility (using the Trail Making Test - Part B) and cognitive inhibition (using the Stroop Colour Word Interference Task). Cardiovascular risk was assessed by means of serum triglyceride levels, body mass index (BMI) and waist circumference, as well as dietary saturated fat intake and a sex-specific cumulative cardiovascular risk score calculated using the Framingham Heart Study method.

RESULTS

Patients with BD had higher BMI and waist circumference, with more BD patients categorized as having central obesity than controls. In the BD group only, higher triglyceride levels were associated with worse cognitive flexibility, and elevated cumulative cardiovascular disease risk was associated with worse cognitive inhibition. No correlations between cardiovascular risk factors and executive function were evident in the control group.

LIMITATIONS

The study was limited by the small sample size and should be considered hypothesis-generating CONCLUSIONS: The associations between triglyceride levels, cumulative cardiovascular disease risk and executive functioning evident in BD in this study preliminarily indicate the potential for mechanistic overlap of physical health and cognitive function in the disorder.

Prognostic factors for steroid-free remission in patients with idiopathic inflammatory myopathies: importance of anthropometric measurements

Background:

Several studies have been conducted on factors associated with mortality in idiopathic inflammatory myopathies (IIMs), but few studies have assessed prognostic factors for steroid-free remission in IIM. We investigated the various clinical factors, including body measurements, that affect IIM treatment outcomes.

Methods:

Patients who were newly diagnosed with IIM between 2000 and 2018 were included. Steroid-free remission was defined as at least 3 months of normalisation of muscle enzymes and no detectable clinical disease activity. The factors associated with steroid-free remission were evaluated by a Cox regression analysis.

Results:

Of the 106 IIM patients, 35 displayed steroid-free remission during follow-up periods. In the multivariable Cox regression analyses, immunosuppressants’ early use within 1 month after diagnosis [hazard ratio (HR) 6.21, 95% confidence interval (CI) 2.61–14.74, p < 0.001] and sex-specific height quartiles (second and third quartiles versus first quartile, HR 3.65, 95% CI 1.40–9.51, p = 0.008 and HR 2.88, 95% CI 1.13–7.32, p = 0.027, respectively) were positively associated with steroid-free remission. Polymyositis versus dermatomyositis (HR 0.21, 95% CI 0.09–0.53, p = 0.001), presence of dysphagia (HR 0.15, CI 0.05–0.50, p = 0.002) and highest versus lowest quartile of waist circumference (WC; HR 0.24, 95% CI 0.07–0.85, p = 0.027) were negatively associated with steroid-free remission.

Conclusion:

The early initiation of immunosuppressant therapy, type of myositis and presence of dysphagia are strong predictors of steroid-free remission in IIM; moreover, height and WC measurements at baseline may provide additional important prognostic value.

The risk of cardiometabolic disorders in lean non-alcoholic fatty liver disease: A longitudinal study

Background

Recent studies suggest that non-alcoholic fatty liver disease (NAFLD) in lean (BMI<25 ​kg/m²) individuals presents a distinct phenotype. We sought to determine the cardiometabolic consequences of lean NAFLD in a population cohort of relatively young asymptomatic individuals who participated in a voluntary routine health promotion evaluation in Brazil.

Methods

We analyzed data in our population collected from 2004 to 2016. Medical and demographic history, anthropometric measures, and fasting blood samples were obtained. Participants had ultrasonography to assess for fatty liver. We defined NAFLD as fatty liver in individuals scoring below 8 on the alcohol use disorders identification test (AUDIT). We included data from 9137 individuals who had complete data at baseline and at follow-up.

Results

The prevalence of lean NAFLD in our cohort was 3.8%. Over the median follow-up period of 2.4 years (range 0.5–9.9 years), lean individuals had 74% (HR: 1.74 (1.39–2.18)) and 67% (1.67 (1.29–2.15)) greater risk of developing elevated BP and elevated glucose, and nearly 3 times the risk of atherogenic dyslipidemia (HR: 2.98 (2.10–4.24)) compared to lean individuals without NAFLD. Lean NAFLD individuals also had higher risk of developing elevated glucose (HR: 1.37 (1.07–1.75)) and atherogenic dyslipidemia (1.46 (1.05–2.01)) compared to non-lean individuals without NAFLD. However, there was no significant difference in the risk of elevated BP, elevated glucose or atherogenic dyslipidemia between lean NAFLD and non-lean individuals with NAFLD in fully adjusted models.

Conclusion

Lean NAFLD is not metabolically benign. Further cardiovascular risk stratification and appropriate preventive measures should be considered in lean individuals who present with NAFLD.

Walking performance is associated with coronary artery calcification in very old adults

BACKGROUND

Coronary artery calcification (CAC) scores have good predictive value for atherosclerosis-related outcomes in the geriatric population. The low availability of cardiac computed tomography is an obstacle to assess CAC in clinical practice. Thus, clinical signs with a good degree of association with CAC can help to estimate cardiovascular risk, particularly in low-income populations.

OBJECTIVES

To assess whether clinical, biochemical and functional measures explain the CAC scores in older individuals.

METHODS

We characterized 89 non-institutionalized older volunteers (≥ 80 years old) by means of a comprehensive biochemical and anthropometric evaluation along with assessments of CAC scores determined by computerized tomography, and tested their association with walking speed test (WS) and handgrip strength (HS) performance.

RESULTS

Analyses of variance showed that body mass index (BMI) and waist circumference (WC) differed significantly (p ≤ 0.01 and p ≤ 0.03; respectively) across quartiles, so that subsequent tests were adjusted for anthropometry. ANCOVA revealed that the two lower quartiles of CAC had better performance in WS compared to the third and fourth quartiles (p ≤ 0.04). Multinomial logistic regression analysis showed that WS scores exhibit enough power (R² = 0.379, p = 0.05) to explain CAC scores. There were no significant differences for HS between quartiles (p = 0.87).

CONCLUSION

WS is associated and explain CAC scores, and may be useful to stratify atherosclerotic burden in apparently healthy very old individuals regardless of body composition.

Central fatness and risk of all cause mortality: systematic review and dose-response meta-analysis of 72 prospective cohort studies

OBJECTIVE

To quantify the association of indices of central obesity, including waist circumference, hip circumference, thigh circumference, waist-to-hip ratio, waist-to-height ratio, waist-to-thigh ratio, body adiposity index, and A body shape index, with the risk of all cause mortality in the general population, and to clarify the shape of the dose-response relations.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

PubMed and Scopus from inception to July 2019, and the reference lists of all related articles and reviews.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Prospective cohort studies reporting the risk estimates of all cause mortality across at least three categories of indices of central fatness. Studies that reported continuous estimation of the associations were also included.

DATA SYNTHESIS

A random effects dose-response meta-analysis was conducted to assess linear trend estimations. A one stage linear mixed effects meta-analysis was used for estimating dose-response curves.

RESULTS

Of 98 745 studies screened, 1950 full texts were fully reviewed for eligibility. The final analyses consisted of 72 prospective cohort studies with 2 528 297 participants. The summary hazard ratios were as follows: waist circumference (10 cm, 3.94 inch increase): 1.11 (95% confidence interval 1.08 to 1.13, I2=88%, n=50); hip circumference (10 cm, 3.94 inch increase): 0.90 (0.81 to 0.99, I2=95%, n=9); thigh circumference (5 cm, 1.97 inch increase): 0.82 (0.75 to 0.89, I2=54%, n=3); waist-to-hip ratio (0.1 unit increase): 1.20 (1.15 to 1.25, I2=90%, n=31); waist-to-height ratio (0.1 unit increase): 1.24 (1.12 to 1.36, I2=94%, n=11); waist-to-thigh ratio (0.1 unit increase): 1.21 (1.03 to 1.39, I2=97%, n=2); body adiposity index (10% increase): 1.17 (1.00 to 1.33, I2=75%, n=4); and A body shape index (0.005 unit increase): 1.15 (1.10 to 1.20, I2=87%, n=9). Positive associations persisted after accounting for body mass index. A nearly J shaped association was found between waist circumference and waist-to-height ratio and the risk of all cause mortality in men and women. A positive monotonic association was observed for waist-to-hip ratio and A body shape index. The association was U shaped for body adiposity index.

CONCLUSIONS

Indices of central fatness including waist circumference, waist-to-hip ratio, waist-to-height ratio, waist-to-thigh ratio, body adiposity index, and A body shape index, independent of overall adiposity, were positively and significantly associated with a higher all cause mortality risk. Larger hip circumference and thigh circumference were associated with a lower risk. The results suggest that measures of central adiposity could be used with body mass index as a supplementary approach to determine the risk of premature death.

Nordic Walking for Overweight and Obese People: A Systematic Review and Meta-Analysis

BACKGROUND

Nordic walking (NW) is a potentially beneficial exercise strategy for overweight and obese people. To date, no reviews have synthesized the existing scientific evidence regarding the effects of NW on this population. This systematic review and meta-analysis aimed to identify the characteristics, methodological quality, and results of the investigations that have studied the effects of NW in overweight and obese individuals.

METHODS

Six electronic databases were searched up to June 2019 for studies that examined the effects of NW on people with a body mass index ≥ 25 kg/m2. The methodological quality of the included randomized controlled trials was retrieved from the physiotherapy evidence database or evaluated using the physiotherapy evidence database scale.

RESULTS

Twelve studies were included in the review. The investigations were mostly good-to-fair methodological quality. NW groups had a significant improvement on parameters such as fasting plasma glucose, abdominal adiposity, and body fat compared with the baseline, but no significant improvements were found when compared with control groups.

CONCLUSIONS

NW can potentially lead to improvements in parameters related to major health outcomes in overweight and obese people. The lack of control for confounding variables in the analyzed studies prevents further elaboration on its potential benefits.

Waist circumference is associated with major adverse cardiovascular events in male but not female patients with type-2 diabetes mellitus

BACKGROUND

Although studies have shown that waist circumference (WC) is positively associated with an increased risk of cardiovascular diseases among the normal population, few studies have investigated WC in patients with type-2 diabetes mellitus (T2DM).

METHODS

This was a post hoc analysis of the Action to Control Cardiovascular Risk in Diabetes (ACCORD) study. The Cox proportional hazards models was used to investigate the relationship between WC and major adverse cardiovascular events (MACEs) in T2DM patients with cardiovascular disease (CVD) or high risk factors of CVD.

RESULTS

A total of 10,251 T2DM patients (6299 men [61.4%], 3952 women [38.6%]) were included in our analysis. The mean age was 64.0 ± 7.53 years. After a mean follow-up at 9.2 ± 2.4 years later, 1804 patients (event rate of 23 per 1000 person-years) had developed MACEs. MACEs rates in men and women were 18.0 and 26.0 events per 1000 person-years, respectively. After multivariable adjustment, each increase in WC of 1 SD increased the risk of MACEs (HR: 1.10, 95% CI 1.04-1.17; P < 0.01) in men, with a non-significant increase in MACEs (HR: 1.04, 95% CI 0.95-1.13; P = 0.40) in women. Compared with those in the first quartile of WC, male patients in the fourth quartile of WC had a hazard ratio (HR) of 1.24 (95% CI 1.05-1.46) for MACEs; female patients in the fourth quartile of WC had an HR of 1.22 (95% CI 0.96-1.56) for MACEs.

CONCLUSIONS

Higher WC is associated with increased risks of MACEs in male but not female T2DM patients. Trial registration URL: http://www.clinicaltrials.gov. Unique identifier: NCT00000620).

Dyslipidaemia prevalence and associated risk factors in the United Arab Emirates: a population-based study

OBJECTIVES

To determine and describe the prevalence and pattern of dyslipidaemia and its associated risk factors among an adult Emirati population.

DESIGN

Population-based, cross-sectional study.

SETTING

Adults living in the Northern Emirates.

PARTICIPANTS

824 adult participants (51.8% men, 48.2% women, mean age 42.8±13.4 years old).

PRIMARY OUTCOME MEASURES

Fasting blood samples were collected, blood pressure and waist circumference were measured.

RESULTS

The overall dyslipidaemia prevalence was 72.5%, with 42.8% of the participants showing high total cholesterol (TC) level, 29% showing high triglyceride (TG) level, 42.5% showing low high-density lipoprotein cholesterol (HDL-C) level, 38.6% showing high low-density lipoprotein cholesterol (LDL-C) level and 72.3% showing high cholesterol ratio. The regression models showed that gender was a significant predictor of a high TG level, low LDL-C level and high cholesterol ratio. Middle-aged individuals (30-59 years old) had a significantly higher risk of having high TC, TG and LDL-C levels than young (<30 years old) and elderly (≥60 years old) individuals. Diabetes mellitus was a significant predictor of low TC, high TG and low HDL-C levels, while central obesity was a significant predictor of a high TG level, low HDL-C level and high cholesterol ratio. Smoking was a significant predictor of a high TG level only in men.

CONCLUSIONS

The prevalence of dyslipidaemia was considerably high among the local adult Emiratis. The identified dyslipidaemia predictors were gender, age, smoking, central obesity and diabetes. Further studies are recommended to assess other important risk factors and aggressive preventive measures in the United Arab Emirates.

Heterogeneity in Metabolic Responses to Dietary Fructose

Consumption of fructose has dramatically increased in past few decades in children and adults. Increasing evidence indicates that added sugars (particularly fructose) have adverse effects on metabolism and lead to numerous cardiometabolic diseases. Although both fructose and glucose are components of sucrose and high fructose corn syrup, the sugars have different metabolic fates in the human body and the effects of fructose on health are thought to be more adverse than glucose. Studies have also shown that the metabolic effects of fructose differ between individuals based on their genetic background, as individuals with specific SNPs and risk alleles seem to be more susceptible to the adverse metabolic effects of fructose. The current review discusses the metabolic effects of fructose on key complex diseases and discusses the heterogeneity in metabolic responses to dietary fructose in humans.

[Not Available]

Objectif

Étudier le risque de mortalité présenté par l’obésité centrale chez les personnes de poids normal, déterminer une mesure clinique pour aider à dépister ce phénotype et examiner les moyens de réduire ce risque.

Qualité des données

La recherche n’a relevé que des études de cohorte prospectives (niveau II) ayant comparé des participants qui présentaient une obésité centrale et un poids normal à des participants dont l’indice de masse corporelle (IMC) était élevé. Des études de niveau I de bonne qualité ont démontré l’effet des interventions liées à l’alimentation et à l’exercice sur l’obésité centrale et la mortalité.

Message principal

Les participants centralement obèses malgré un IMC normal et qui sont atteints de dyslipidémie athérogène présentent un risque comparable, sinon supérieur, de mortalité que les participants qui sont centralement obèses en plus d’être en surpoids ou obèses selon l’IMC. Le rapport entre le tour de taille et la taille^* serait la mesure clinique la plus pragmatique de l’obésité centrale. Le régime méditerranéen est une intervention efficace pour stopper la prise pondérale tout en réduisant la ceinture abdominale. Un faible niveau d’exercice réduit aussi le tour de taille. La perte pondérale ne doit pas constituer l’objectif.

Conclusion

Un rapport entre le tour de taille et la taille de plus de 0,5 malgré un IMC normal indique un risque élevé de mortalité par atteinte cardiométabolique. Ce risque serait équivalent, voire supérieur, au risque présenté par les patients centralement obèses en plus d’être en surpoids ou obèses. De légères interventions liées à l’alimentation et à l’exercice sont efficaces pour réduire ce risque.

Normal-weight central obesity: Unique hazard of the toxic waist

OBJECTIVE

To examine the mortality risk presented by normal-weight central obesity, to identify a clinical measure to aid in the identification of this phenotype, and to explore the means for mitigation of this risk.

QUALITY OF EVIDENCE

Only prospective cohort studies (level II) comparing participants with central obesity at normal weight with those at higher levels of body mass index (BMI) were found. Good level I studies were available to demonstrate the effect of diet and exercise interventions on central obesity and mortality.

MAIN MESSAGE

Participants with atherogenic dyslipidemia who are centrally obese at normal BMI are at similar, and possibly higher, mortality risk compared with those who are centrally obese and overweight or obese according to their BMI. Waist-to-height ratio might be the most pragmatic clinical measure of central obesity. The Mediterranean diet is an effective intervention to prevent ongoing weight gain while reducing abdominal girth. Low levels of exercise can also reduce waist circumference. Weight loss need not be an objective.

CONCLUSION

A waist-to-height ratio exceeding 0.5 at normal BMI identifies elevated mortality risk for cardiometabolic disease. This risk might equal or exceed that of centrally obese patients who are overweight or obese. Modest dietary and exercise interventions can be effective in mitigation of this risk.

Estimates of the current and future burden of cancer attributable to excess body weight and abdominal adiposity in Canada

The increasing prevalence of obesity among Canadians has important implications for newly diagnosed cases of cancer given that excess body weight and abdominal adiposity are known to increase the risk of several cancers. The purpose of this analysis was to estimate the current attributable and future avoidable burden of cancer related to excess body weight and abdominal adiposity among Canadian adults. We estimated the population attributable risk (PAR) for all cancers associated with excess body weight and abdominal adiposity using contemporary cancer incidence, relative risk and exposure prevalence data for body mass index (BMI), waist circumference and waist-to-hip-ratio. Using the partial impact fraction (PIF), we also estimated the future avoidable burden of cancer from 2015 to 2042 in Canada, and by province, through various hypothetical intervention scenarios. In 2003, approximately half (50.5%) of the Canadian population was estimated to be overweight (BMI 25.0-29.9) or obese (BMI ≥30.0), 56.5% to have excess abdominal adiposity and 56.8% with a high waist-to-hip ratio. In 2015, the estimated PARs of all incident cancers associated with excess body weight, excess abdominal adiposity and high waist-to-hip ratio were 7.2%, 8.9% and 10.0%, respectively. If the population BMI could revert to its 1994 distribution, 72,157 associated cancer cases could be prevented cumulatively by 2042. A reduction in excess body weight and abdominal adiposity has the potential to decrease the future cancer burden in Canada substantially, and hence efforts to reverse increasing trends in obesity should be prioritized.

Impact of Obesity on Postoperative Outcomes following cardiac Surgery (The OPOS study): rationale and design of an investigator-initiated prospective study

INTRODUCTION

Increasing levels of obesity worldwide have led to a rise in the prevalence of obesity-related complications including cardiovascular risk factors such as diabetes, hypertension and dyslipidaemia. Healthcare providers believe that overweight and obese cardiac surgery patients are more likely to experience adverse postoperative outcomes. The body mass index (BMI) is the primary measure of obesity in clinical practice, without accounting for a patient's level of cardiopulmonary fitness or muscle mass. The objective of this study is to determine whether fitness capacity of obese cardiac surgical patients and biomarkers, alone or in combination, will help identify patients at risk for adverse outcomes when undergoing cardiac surgery.

METHODS AND ANALYSIS

Patients between the ages of 18 and 75 years undergoing elective cardiac surgery are consented to participate in this prospective observational study. Patients will be invited to participate in measures of obesity, functional capacity and exercise capacity assessments, quality of life questionnaires, and blood and tissue sampling for biomarker analysis. The endpoints evaluated are measures other than BMI that could be predictive of short-term and long-term postoperative outcomes. Clinical outcomes of interest are prolonged ventilation, hospital length of stay, renal failure and all-cause mortality. Biomarkers of interest will largely focus on metabolism (lipids, amino acids) and inflammation (adipokines, cytokines and chemokines).

ETHICS AND DISSEMINATION

This study has been approved by the institutional review board at the Horizon Health Network. On completion of the study, the results shall be disseminated through conference presentations and publications in peer-reviewed journals. Additionally, the report shall also be diffused more broadly to the general public and the cardiovascular community.

TRIAL REGISTRATION NUMBER

NCT03248921.

Oral Glutamine Supplementation Reduces Obesity, Pro-Inflammatory Markers, and Improves Insulin Sensitivity in DIO Wistar Rats and Reduces Waist Circumference in Overweight and Obese Humans

In the present study, we aimed to investigate whether chronic oral glutamine (Gln) supplementation may alter metabolic parameters and the inflammatory profile in overweight and obese humans as well as whether Gln may modulate molecular pathways in key tissues linked to the insulin action in rats. Thirty-nine overweight/obese volunteers received 30 g of Gln or alanine (Ala-control) for 14 days. Body weight (BW), waist circumference (WC), hormones, and pro-inflammatory markers were evaluated. To investigate molecular mechanisms, Gln or Ala was given to Wistar rats on a high-fat diet (HFD), and metabolic parameters, euglycemic hyperinsulinemic clamp with tracers, and Western blot were done. Gln reduced WC and serum lipopolysaccharide (LPS) in overweight volunteers. In the obese group, Gln diminished WC and serum insulin. There was a positive correlation between the reduction on WC and LPS. In rats on HFD, Gln reduced adiposity, improved insulin action and signaling, and reversed both defects in glucose metabolism in the liver and muscle. Gln supplementation increased muscle glucose uptake and reversed the increased hepatic glucose production, in parallel with a reduced glucose uptake in adipose tissue. This insulin resistance in AT was accompanied by enhanced IRS1 O-linked-glycosamine association in this tissue, but not in the liver and muscle. These data suggest that Gln supplementation leads to insulin resistance specifically in adipose tissue via the hexosamine pathway and reduces adipose mass, which is associated with improvement in the systemic insulin action. Thus, further investigation with Gln supplementation should be performed for longer periods in humans before prescribing as a beneficial therapeutic approach for individuals who are overweight and obese.

Central body fatness is a stronger predictor of cancer risk than overall body size

The importance of body size versus weight distribution for cancer risk is unclear. We investigated associations between measures of body size and shape and the risk of developing cancer. The study population consisted of 26,607 participants from the Alberta’s Tomorrow Project cohort. Two main measures of body shape and size were examined: i) body mass index (BMI) and ii) waist circumference (WC). Incident cancers were identified via linkage to the Alberta Cancer Registry. Cox proportional hazards models were used. Males and females classified as obese (BMI ≥ 30 kg /m⁻²) have a 33% and 22% increased risk of all-cancer, respectively, than their normal weight counterparts. Similar all-cancer risk increases are observed for those above sex-specific WC guidelines. Mutual adjustment for WC attenuates the association between BMI and all-cancer risk, especially among females. Central adiposity appears to be a stronger predictor of all-cancer risk than body size.

Obesity is linked to increased cancer risk but the impact of body size versus weight distribution in determining the increased risk is unclear. Here the authors examined body mass index, waist circumference, and waist to hip ratio in relation to all-cancer incidence and incidence of seven individual cancers in a population of approximately 26,000 individual and conclude that central adiposity appears to be a stronger predictor of all-cancer risk than body size.