Subclinical vascular inflammation in subjects with normal weight obesity and its association with body fat: an 18 F-FDG-PET/CT study

Assessing the Risk of Normal Weight Obesity in Korean Women across Generations: A Study on Body Composition and Physical Fitness

Normal weight obesity (NWO) refers to a condition in which the body mass index falls within the normal range, but the percent of body fat is excessive. Although there are reports of a high prevalence of cardiovascular and metabolic diseases in NWO, analyses regarding physical fitness have been lacking. Therefore, the purpose of this study was to analyze the age-related prevalence of NWO and to examine physical fitness across generations. Our study utilized a dataset comprising 119,835 participants for analysis. The prevalence of NWO across ages was examined using cross-tabulation analysis. For body composition and physical fitness, medians and group differences were assessed by generation through Kruskal-Wallis and Bonferroni post hoc tests. Additionally, univariate logistic regression was adopted to analyze the odds ratio. The prevalence of NWO in Korean women was 18.3%. The fat-free mass of the NWO group was consistently lower than that of both the group with normal body mass indexes (Normal) and obese body mass indexes (Obesity) across all generations. Additionally, the waist circumference and blood pressure were greater in the now group than in the Normal group. When considering maximal strength, muscle endurance, power, balance, and coordination, the NWO group exhibited lower levels compared to the Normal group. The NWO group showed lower muscle mass than both the Normal and Obesity groups, resulting in significantly reduced physical fitness compared to that of the Normal group, similar to the Obesity group. This condition may increase not only the risk of posing a potentially more serious health concern than obesity but also the risk of falls in elderly people. Therefore, based on this study, it is crucial to not only define obesity using BMI criteria but also to diagnose NWO. Public health policies and preventive measures must be implemented accordingly.

Triglyceride-glucose index is capable of identifying metabolically obese, normal-weight older individuals

BACKGROUND

The concept of metabolically obese, normal weight (MONW) has emerged to describe individuals with a normal body mass index (BMI) who are at a relatively high risk of chronic diseases. However, BMI itself is a suboptimal index for the assessment of the health risks associated with visceral fat. The triglyceride-glucose (TyG) index is considered to be a reliable and cost-effective marker of insulin resistance. Therefore, in the present study, we aimed to determine the TyG index cut-off values that could be used to define MONW in older people and to determine the usefulness of these values for the prediction of chronic diseases.

METHODS

A total of 4,721 participants in the Korea National Health and Nutritional Examination Survey who were ≥ 60 years of age and did not have underweight or obesity were included. MONW was defined using the criteria for metabolic syndrome (MS), and the TyG index was calculated on the basis of the fasting plasma triglyceride and glucose concentrations. Chronic diseases, including T2DM, hypertension, and non-alcoholic fatty liver disease (NAFLD), were diagnosed.

RESULTS

The prevalence of MS increased from the lowest to the highest TyG index tertile. The cut-off values of the TyG index for MONW were calculated as 8.88 and 8.80 for males and females, respectively. MONW, defined using these cut-off values, was associated with high odds ratios for NAFLD, T2DM, and hypertension in both males and females.

CONCLUSIONS

The TyG index cut-off values calculated in the present study can be used to discriminate individuals with MONW from other older individuals without obesity and to predict the risk of chronic diseases. These findings show that the TyG index is an effective and cost-efficient method of assessing the risk of chronic diseases in people with MONW.

Association between normal-weight obesity and bone mineral density in older Korean adults: A population-based cross-sectional study

The effects of normal-weight obesity, which is defined as having a high level of body fat despite a normal body mass index, on the health of bones in older adults are poorly understood. This cross-sectional study examined the relationship between normal-weight obesity and bone mineral density in Korean adults aged 50 years or more (2815 men and 2744 women) from the 2008-2011 Korea National Health and Nutrition Examination Surveys. Between the ages of 50 and 69 years, individuals with normal-weight obesity had a higher risk of low bone mineral density (odds ratio = 1.596, 95 % confidence interval = 1.189-2.141, p = 0.002) compared with individuals with normal-weight non-obesity. However, no significant association between normal-weight obesity and bone mineral density was observed among people between the ages of 70 and 89 years. The study findings support the clinical significance of normal-weight obesity as a proxy biomarker to identify in primary care settings people who are at increased risk of developing osteoporosis at an early stage of aging.

Clinical Classification of Obesity and Implications for Metabolic Dysfunction-Associated Fatty Liver Disease and Treatment

Obesity,and metabolic dysfunction-associated fatty liver disease (MAFLD) have reached epidemic proportions globally. Obesity and MAFLD frequently coexist and act synergistically to increase the risk of adverse clinical outcomes (both hepatic and extrahepatic). Type 2 diabetes mellitus (T2DM) is the most important risk factor for rapid progression of steatohepatitis and advanced fibrosis. Conversely, the later stages of MAFLD are associated with an increased risk of T2DM incident. According to the proposed criteria, MAFLD is diagnosed in patients with liver steatosis and in at least one in three: overweight or obese, T2DM, or signs of metabolic dysregulation if they are of normal weight. However, the clinical classification and correlation between obesity and MAFLD is more complex than expected. In addition, treatment for obesity and MAFLD are associated with a reduced risk of T2DM, suggesting that liver-based treatments could reduce the risk of developing T2DM. This review describes the clinical classification of obesity and MAFLD, discusses the clinical features of various types of obesity and MAFLD, emphasizes the role of visceral obesity and insulin resistance (IR) in the development of MAFLD,and summarizes the existing treatments for obesity and MAFLD that reduce the risk of developing T2DM.

Obesity phenotypes and cardiovascular risk: From pathophysiology to clinical management

Obesity epidemic reached the dimensions of a real global health crisis with more than one billion people worldwide living with obesity. Multiple obesity-related mechanisms cause structural, functional, humoral, and hemodynamic alterations with cardiovascular (CV) deleterious effects. A correct assessment of the cardiovascular risk in people with obesity is critical for reducing mortality and preserving quality of life. The correct identification of the obesity status remains difficult as recent evidence suggest that different phenotypes of obesity exist, each one associated with different degrees of CV risk. Diagnosis of obesity cannot depend only on anthropometric parameters but should include a precise assessment of the metabolic status. Recently, the World Heart Federation and World Obesity Federation provided an action plan for management of obesity-related CV risk and mortality, stressing for the instauration of comprehensive structured programs encompassing multidisciplinary teams. In this review we aim at providing an updated summary regarding the different obesity phenotypes, their specific effects on CV risk and differences in clinical management.

The Relationship of Body Fat Ratio to Anthropometric and Metabolic Parameters in Normal Weight and Overweight Women; The Concept of Normal Weight Obesity

Aim: We aimed to underline the importance of “normal weight obesity concept”, prevent the overlooking of Normal Weight Obesity patients, administrate their treatments and explain them the risks regarding their future lives along with making emphasis on the necessity of change in polyclinical practices about the subject. Methods: We selected 200 female patients that were either normal or overweighted for this study. Patients have been divided into 4 groups with respect to their body mass index and body fat percent values. Differences of bioelectrical impedance analysis measurements between the groups, relation of the anthropometric and metabolic parameters and those parameters’ inner correlations have been inspected. Results: Serum levels of fasting plasma glucose, insulin, HOMA-IR, total cholesterol, LDL, triglyceride and TSH were higher in “Normal Weight Obesity” subjects than “Normal Weight Lean” subjects. The mean LDL levels were found to be higher in the Normal Weight Obesity group compared to the other groups and it was found to be statistically significant. Body fat percent was positively correlated to insulin, HOMA-IR, visceral fat rating, waist – hip circumferences, waist to height – hip to height ratios. Conclusion: The importance of measurement of body fat percent and not to overlook the Normal Weight Obesity patients should be emphasized once more. Therefore, in the primary care, during public screening and polyclinical assessment states, patients should be checked for obesity with not only measuring their weights and heights, but also detection of their detailed body composition. Keywords: obesity, body fat distribution, waist to height ratio

Bone mineral density and normal-weight obesity syndrome: beyond body weight and body mass index

INTRODUCTION

This study aimed to evaluate, for the first time, the bone profile of adult women and men with and without normal-weight obesity (NWO) syndrome and its association with bone health-related nutrient intake, anthropometry, and body composition.

MATERIALS AND METHODS

This was a cross-sectional study of adults aged between 20 and 59 years with normal body weight, separated according to body fat (BF) percentage into NWO and non-NWO syndrome groups. BF > 30% and > 19% were considered high for women and men, respectively. Socioeconomic, physical activity, food consumption, anthropometric, and body composition data were evaluated. Student's t-test or Mann-Whitney test and Pearson's χ² or Fisher's exact tests were applied for comparisons. Multiple linear regression models were developed, with bone parameters as the dependent variables and anthropometric, body composition, and food consumption data as the main independent variables.

RESULTS

The sample consisted of 224 adults (69.2% women) with a median (interquartile range) age of 23 (21-25) years, 71% of whom had NWO syndrome. Compared with women, a higher percentage of men had a lower-than-expected spinal bone mineral density (BMD) Z-score for age (10%; p = 0.0214). Bone parameters were similar between groups. Spinal BMD was negatively associated with male sex and positively associated with body weight. The femoral BMD was negatively associated with BF percentage and positively associated with body mass index.

CONCLUSION

The negative association of BMD with BF percentage may suggest a higher risk of bone alterations in individuals with NWO syndrome and should be monitored over time.

Characterization and prevalence of obesity among normal weight college students

Normal weight obesity (NWO) describes individuals who have a normal weight body mass index (BMI), but have an unhealthy amount of body fat. Based on the life-long habits that develop during college, exploring NWO among a college-aged population may be essential in identifying and preventing obesity that develops in early adulthood. This study aimed to characterize NWO among young adults with normal weight BMI. 94 college students (Mean ± SD: Age: 19.6 ± 1.5 yrs; BMI: 21.9 ± 1.8 kg/m²) enrolled during the Fall semester (Aug-Oct) were assessed for body composition by dual energy X-ray absorptiometry to determine body fat percentage, fat mass, lean mass and trunk fat; lifestyle habits were characterized from validated questionnaires. Mean arterial pressure and metabolic biomarkers [total cholesterol, high density lipoproteins, non-high density lipoproteins, and glucose] were evaluated for cardiometabolic health. NWO was defined using data from the National Health and Nutrition Examination Survey (NHANES) for body fat percentage. Data was analyzed by group (NWO vs NWL) and sex. with independent t-tests to investigate continuous data, and chi-square test of independence for categorical data. Rates of NWO for the total sample were 13.8%. Males (n=30) had a higher rate of NWO (26.7%) compared to females (n=64; 7.8%). NWO individuals had higher fat mass (p=0.024), trunk fat (p<0.001), and larger waist to hip ratio (p<0.001) than normal weight lean. NWO also engaged in less vigorous physical activity (p=0.043). The occurrence of NWO among otherwise healthy college students is evident. Identification of these individuals may be an effective component for obesity prevention and treatment. Determining feasible methods to measure body fat in this population is essential, as BMI may mask obesity in a young adult population.

Are Women with Normal-Weight Obesity at Higher Risk for Cardiometabolic Disorders?

OBJECTIVES

This study aimed to evaluate the cardiometabolic abnormalities in women with normal-weight obesity (NWO) in comparison with lean, overweight, and obese women.

METHODS

This cross-sectional study evaluated the assessment of cardiometabolic abnormalities of women with NWO compared to lean, overweight, and obese women. NWO was defined as a BMI < 25 kg.m^-2 and a BFP higher than 30%. Anthropometric variables, cardiometabolic abnormality markers (fasting blood glucose (FBG), blood pressure (BP), lipid profile, insulin resistance, and high-sensitivity C-reactive protein (hs-CRP)), and liver enzymes were also examined.

RESULTS

Significant differences were observed in HDL concentrations between NWO, lean, and obese participants (p < 0.05). There were no significant differences in FBG, insulin resistance, liver enzymes, or cholesterol between groups (p > 0.05). The prevalence of the abnormal metabolic phenotype was higher in NWO compared to the lean group (4.0% and 24.1%, respectively; p < 0.05). Women with type 2 and 3 obesity had abnormal metabolic profiles (60.9% and 73.9%, respectively) compared to NWO participants (p < 0.01). The NWO group had a significantly higher incidence of cardiometabolic abnormalities compared to the lean participants (p < 0.05), while the type 2 and 3 obese individuals had significantly higher incidences compared to the NWO group (p < 0.001 and p < 0.001, respectively).

CONCLUSIONS

Individuals with NWO had a significantly higher incidence of cardiometabolic abnormalities when compared to lean participants. These abnormalities strongly relate to BFP and waist circumferences.

Association of normal weight obesity phenotype with inflammatory markers: A systematic review and meta-analysis

Background

Individuals with normal weight could suffer from obesity based on their body fat percentage (also known as normal weight obesity (NWO)), thus being at risk of significant morbidity and mortality compared to the general population. It seems that inflammatory pathways and chronic inflammation are significant contributors to the pathogenicity of NWO. This study aimed to assess and pool the association of proinflammatory and anti-inflammatory cytokines with NWO.

Methods

In this systematic review and meta-analysis, online international databases (PubMed, Scopus, EMBASE, Web of Science, and Google Scholar) were searched until August 2022. All observational studies with an English full text comparing the mean levels of proinflammatory and anti-inflammatory cytokines (e.g., C-reactive protein (CRP), various types of interleukins (IL) s, tumor necrosis factor-alpha (TNF)) and white blood cell (WBC) count, in subjects with NWO and "normal weight non-obese (NWNO)" were included. Two researchers independently screened, reviewed and assessed the quality of included studies. The remaining articles' data were extracted post-screening. The heterogeneity between studies was assessed using the I² and Cochran's Q tests. A random effect model meta-analysis was used to pool the standardized mean difference (SMD) as an effect size.

Results

From the initial 559 studies, 21 and 19 were included in the qualitative and quantitative synthesis, respectively. In the systematic review, 8 studies reported a significant association between various proinflammatory cytokines (CRP, IL₆, IL_1β, and TNFα) and NWO. According to random-effect meta-analysis, the association between NWO with CRP (SMD: 0.60, 95% CI: 0.30, 0.91) and IL6 (SMD: 0.90, 95%CI: 0.14, 1.66) was statistically significant. Moreover, the mean level of TNF_α in subjects with NWO and NWNO did not differ significantly (SMD: 0.67, 95% CI: -0.36, 1.70).

Conclusion

The findings of this study show that NWO was associated with high levels of CRP and IL6. Therefore, inflammatory pathways may play a role in the pathogenicity of NWO.

Postprandial triglycerides, endothelial function, and inflammatory cytokines as potential candidates for early risk detection in normal-weight obesity

PROBLEM

Normal-weight obesity (NWO) is associated with increased cardiovascular disease (CVD) risk. However, NWO's clinical presentation is often unremarkable based on common risk factors. We examined whether CVD risk factors not routinely measured clinically including postprandial triglycerides, flow-mediated dilation (FMD), and inflammatory cytokines would be abnormal in NWO, consistent with their future risk.

METHODS

Individuals were recruited into 3 groups (n = 10/ group): controls (Con), NWO, and metabolic syndrome (MetS). Con was defined as a normal body mass index (BMI), < 25% (M) or < 35% (F) body fat, and < 1 International Diabetes Federation (IDF) criteria. NWO were above this body fat cutoff while maintaining a normal BMI and MetS was defined per the IDF. Participants underwent an abbreviated fat tolerance test (i.e., difference in fasting and 4 h triglycerides following a high-fat meal [9 kcal/kg; 73% fat)] and fasting and postprandial lipid and glucose metrics, as well as FMD were measured. A T cell cytokine bioplex was also performed using fasting serum.

RESULTS

NWO and MetS had similar body fat% and both were higher than Con (p < 0.0001). Despite having similar fasting triglycerides to Con, NWO had 4-hour triglycerides 66% greater than Con, but 46% lower than MetS (p < 0.01). FMD decreased in all groups after the high-fat meal (p < 0.0001). MetS displayed lower fasting FMD than Con, and NWO was similar to both groups (p < 0.05). No group differences were observed with postprandial FMD and the majority of fasting cytokines assessed. However, MetS exhibited higher fasting TNF-α than Con (p < 0.05), and NWO was similar to both groups.

CONCLUSIONS

Overall, NWO was associated with higher postprandial triglycerides than Con, but displayed little evidence of impaired vascular health or inflammation.

Cardiometabolic risk factors in adults with normal weight obesity: A systematic review and meta-analysis

Normal weight obesity (NWO) is a new emerging phenotype of obesity, defined as a normal body mass index with a high body fat percentage. While several studies have described the impact of NWO on cardiometabolic risk factors, the association between them remains uncertain. This meta-analysis systematically evaluated cardiometabolic risk factors in adults with NWO compared to adults with normal weight lean (NWL). A systematic literature search was performed from the inception until September 21, 2021 in order to comprehensively search for all observational studies that had three important variables, including adults (age ≥18 years old), NWO and cardiometabolic risk factors including metabolic syndrome, hypertension, diabetes mellitus, dyslipidaemia or all laboratory findings related to cardiometabolic risk factors. Twenty-four cross-sectional studies with a total of 75 201 subjects are included in the qualitative and quantitative analysis. Overall, older age and female sex are more likely in NWO population. Compared to NWL, NWO is significantly associated with cardiometabolic risk factors, including metabolic syndrome (OR = 2.24 [1.74, 2.89]; p < .001; I²  = 76%, P_{heterogeneity}  < 0.001), hypertension (OR = 1.60[1.36, 1.89]; p < .001; I²  = 76%, P_{heterogeneity}  < 0.001), diabetes mellitus (OR = 1.72[1.54, 1.92]; p < .001; I²  = 47%, P_{heterogeneity}  < 0.001), dyslipidaemia (OR = 1.50 [1.03, 2.18]; p = .03; I²  = 94%, P_{heterogeneity}  < 0.001) and other laboratory findings, except for C-reactive protein in both sexes group; and adiponectin levels in female group. Our meta-analysis showed that NWO was associated with cardiometabolic risk factors. Thus, the traditional definition of obesity using the BMI criteria should be challenged, as those with NWO might still be exposed to a heightened risk of cardiometabolic disorders. Nonetheless, further prospective cohort studies are needed better to understand this syndrome.

Association of waist circumference with muscle and fat mass in adults with a normal body mass index

BACKGROUND/OBJECTIVES

We aimed to investigate the association of waist circumference (WC) with body composition among individuals with a normal body mass index (BMI) to distinguish muscle and fat mass, as both affect health differently.

SUBJECTS/METHODS

We analyzed dual-energy X-ray absorptiometry data (derived from the Korean National Health and Nutrition Survey, which includes information on fat and lean mass) of 7,493 adults with a normal BMI. Subjects were categorized into four groups of increasing WC. The fourth group was defined as being centrally obese. Each number of subjects are as follows: 1,870, 695, 231, and 39 among men and 3,054, 1,100, 406, and 98 among women. We conducted a sex-stratified linear regression analysis of body composition according to WC group after adjustments for covariates.

RESULTS

We observed a positive association of body fat with increasing WC in both men and women (all P for trend: < 0.001). The adjusted mean values for percent body fat with 95% confidence intervals (CIs) according to the four WC groups in ascending order were 17.8 (17.5–18.3), 21.0 (20.6–21.5), 22.1 (21.5–22.8), and 25.1 (24.2–26.1) in men and 29.7 (29.4–30.0), 32.0 (31.6–32.3), 32.9 (32.4–33.4), and 34.7 (33.2–36.1) in women. However, there was an inverted J-shaped association between muscle mass and WC. The fourth group had a higher percent body fat and lower muscle mass than other groups. The adjusted mean values for appendicular skeletal muscle mass index (kg/m²) with 95% CIs according to the four WC groups in ascending order were 7.55 (7.51–7.59), 7.62 (7.56–7.68), 7.65 (7.56–7.74), and 7.22 (7.04–7.41) in men and 5.83 (5.80–5.85), 5.96 (5.92–6.00), 6.03 (5.96–6.10), and 5.88 (5.73–6.03).

CONCLUSIONS

There was a positive association between body fat and WC among individuals with normal BMI; conversely there was an inverted J-shaped association between lean body mass and WC. Our findings support the WC measurement should be included in obesity evaluations for adults with a normal BMI.

Normal weight obesity and unaddressed cardiometabolic health risk-a narrative review

Normal weight obesity (NWO) is defined as having a normal body mass index (BMI), but a high body fat mass. There is growing interest in individuals with NWO, which is an underdiagnosed and understudied group, because of their increased risk for cardiometabolic morbidity and mortality. In this review, we summarized the definition, prevalence, etiology, pathophysiology, and cardiovascular outcomes seen in NWO. We have also summarized the available literature on interventions for NWO. There is a wide variation in the body fat percent cutoffs used to diagnose excess body fat. Hence, the prevalence rates of NWO vary between different populations and studies. It is estimated that about 30 million Americans have NWO and the worldwide prevalence ranges from 4.5% to 22%. Genetics, diet, and physical activity are related to NWO. However, etiological factors are not clear. Changes in body composition, inflammation, oxidative stress are present in NWO in comparison to normal weight lean (NWL) who have a normal BMI and normal body fat amount. Furthermore, cardiometabolic changes are observed and some are subclinical. Thus, screening for NWO will enhance the primary prevention of cardiovascular disease. Due to the use of various body fat percent cutoffs and methods to measure body fat, it is challenging to compare between studies. Researchers working in this field should ideally work towards developing standard body fat percent cutoffs for diagnosing NWO. There are many gaps in the literature on NWO unlike for overt obesity and future studies should explore the etiology, molecular mechanisms, and adipose tissue changes of NWO as well as conduct well planned and executed randomized controlled trials testing dietary, physical, and behavioral interventions for NWO in both males and females of different racial and age groups.

Inflammatory Biomarkers and Components of Metabolic Syndrome in Adolescents: a Systematic Review

Metabolic syndrome (MetS) has been prevalent among adolescents. The association between the concentration of inflammatory markers and the individual components of the metabolic syndrome indicates that inflammation, when there is no recent or ongoing disease, mediated by an inflammatory process, is an event that may precede the development of metabolic disorders in teenagers. The objective of this study is to verify the association of inflammatory biomarkers with the components of metabolic syndrome in adolescents. From a search of 3 databases, 13 articles met the study inclusion criteria. Two investigators independently extracted data from included studies. The evaluated inflammatory biomarkers are related to the components of MetS (insulin resistance, central and visceral obesity, arterial hypertension, dyslipidemia), which may increase the risk of developing the syndrome in adolescents. The results of this review are of clinical relevance, since the evaluation of inflammatory biomarkers in the presence of metabolic alterations can help to identify the risk factors that lead to the progression of MetS in adolescents.

Cardiometabolic risk and health behaviours in adolescents with normal-weight obesity: a systematic review

OBJECTIVE

To analyse the presence of cardiometabolic risk factors in adolescents with normal-weight obesity (NWO), as well as to investigate health behaviours related to the phenotype.

DESIGN

The study was conducted according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines and the bibliographic search was carried out in the PubMed, Scielo and ScienceDirect databases.

SETTING

School, university and population.

PARTICIPANTS

Adolescents between 10 and 19 years old.

RESULTS

A total of eight papers were included. Most studies have found a relationship between NWO and the presence of cardiometabolic risk factors, such as high waist circumference, unfavourable lipid and glycid profile. As for health behaviours, three of the eight studies included evaluated eating habits; however, the results were not conclusive. In addition, four studies analysed the practice of physical activity or physical fitness, which was lower in NWO.

CONCLUSIONS

The available evidence indicates that NWO is related to the early development of cardiometabolic changes, physical inactivity and less physical fitness in adolescents. The results also reveal the importance of early detection of the phenotype, as well as the need for further research on the associated factors to prevent future diseases. Registration (PROSPERO: CRD42020161204).

Prevalence of normal weight obesity and its associated cardio-metabolic risk factors - Results from the baseline data of the Kerala Diabetes Prevention Program (KDPP)

Background

Cardiometabolic disorders are frequently observed among those who have obesity as measured by body mass index (BMI). However, there is limited data available on the cardiometabolic profile of those who are non-obese by BMI but with a high body fat percentage (BFP), a phenotype frequently observed in the Indian population. We examined the prevalence of individuals with normal weight obesity (NWO) and the cardiometabolic profile of NWO individuals at high risk for type 2 diabetes(T2D) in a south Asian population.

Material and methods

In the Kerala Diabetes Prevention Program, individuals aged between 30 to 60 years were screened using the Indian Diabetes Risk Score(IDRS) in 60 rural communities in the Indian state of Kerala. We used data from the baseline survey of this trial for this analysis which included 1147 eligible high diabetes risk individuals(IDRS >60). NWO was defined as BMI within the normal range and a high BFP (as per Asia-pacific ethnicity based cut-off); Non-obese (NO) as normal BMI and BFP and overtly obese (OB) as BMI ≥25 kg/m² irrespective of the BFP. Data on demographic, clinical and biochemical characteristics were collected using standardized questionnaires and protocols. Body fat percentage was assessed using TANITA body composition analyser (model SC330), based on bioelectrical impedance.

Results

The mean age of participants was 47.3 ± 7.5 years and 46% were women. The proportion with NWO was 32% (n = 364; 95% CI: 29.1 to 34.5%), NO was 17% (n = 200) and OB was 51% (n = 583). Among those with NWO, 19.7% had T2D, compared to 18.7% of those who were OB (p value = 0.45) and 8% with NO (p value = 0.003). Among those with NWO, mean systolic and diastolic blood pressure were 129 ± 20; 78 ± 12 mmHg, compared to 127 ± 17; 78±11 mmHg among those with OB (p value = 0.12;0.94) and 120 ± 16; 71±10 mmHg among with NO (p value<0.001; 0.001), respectively. A similar pattern of association was observed for LDL cholesterol and triglycerides. After adjusting for other risk factors, the odds of having diabetes (OR:2.72[95% CI:1.46–5.08]) and dyslipidemia (2.37[1.55–3.64]) was significantly more in individuals with NWO as compared to non-obese individuals.

Conclusions

Almost one-third of this South Asian population, at high risk for T2D, had normal weight obesity. The significantly higher cardiometabolic risk associated with increased adiposity even in lower BMI individuals has important implications for recognition in clinical practice.

Development and validation of prediction equations for the assessment of muscle or fat mass using anthropometric measurements, serum creatinine level, and lifestyle factors among Korean adults

BACKGROUND/OBJECTIVES

The measurement of body composition, including muscle and fat mass, remains challenging in large epidemiological studies due to time constraint and cost when using accurate modalities. Therefore, this study aimed to develop and validate prediction equations according to sex to measure lean body mass (LBM), appendicular skeletal muscle mass (ASM), and body fat mass (BFM) using anthropometric measurement, serum creatinine level, and lifestyle factors as independent variables and dual-energy X-ray absorptiometry as the reference method.

SUBJECTS/METHODS

A sample of the Korean general adult population (men: 7,599; women: 10,009) from the Korean National Health and Nutrition Examination Survey 2008–2011 was included in this study. The participants were divided into the derivation and validation groups via a random number generator (with a ratio of 70:30). The prediction equations were developed using a series of multivariable linear regressions and validated using the Bland–Altman plot and intraclass correlation coefficient (ICC).

RESULTS

The initial and practical equations that included age, height, weight, and waist circumference had a different predictive ability for LBM (men: R² = 0.85, standard error of estimate [SEE] = 2.7 kg; women: R² = 0.78, SEE = 2.2 kg), ASM (men: R² = 0.81, SEE = 1.6 kg; women: R² = 0.71, SEE = 1.2 kg), and BFM (men: R² = 0.74, SEE = 2.7 kg; women: R² = 0.83, SEE = 2.2 kg) according to sex. Compared with the first prediction equation, the addition of other factors, including serum creatinine level, physical activity, smoking status, and alcohol use, resulted in an R² that is higher by 0.01 and SEE that is lower by 0.1.

CONCLUSIONS

All equations had low bias, moderate agreement based on the Bland–Altman plot, and high ICC, and this result showed that these equations can be further applied to other epidemiologic studies.

The effect of 12 weeks of euenergetic high-protein diet in regulating appetite and body composition of women with normal-weight obesity: a randomised controlled trial

Normal-weight obesity (NWO) syndrome is associated with metabolic diseases. The present study aimed to investigate the effects of 12 weeks of a high-protein (HP) v. a standard protein (SP) diet on appetite, anthropometry and body composition in NWO women. In this clinical trial, fifty NWO women were randomly allocated to HP (n 25) or SP (n 25) diet groups. Women in the HP and SP groups consumed 25 and 15 % of their total energy intake from protein for 12 weeks. Weight, fat mass (FM), lean body mass (LBM), waist circumference (WC) and appetite were evaluated at baseline and following their 3-month intervention. After 12 weeks, the LBM was higher in HP compared with no significant changes in the SP group (mean between-group difference = 1·5 kg; 95 % CI 3·1, 0·01; effect size (d) = 0·4). Furthermore, the HP group had lower FM (mean between-group difference -1·1 kg; 95 % CI 1, -3·3; d = -0·2), body fat percentage (BFP) (mean between-group difference -2 %; 95 % CI 0·7, -5·2; d = -0·3) and WC (mean between-group difference -1·4 cm; 95 % CI 0·6, -3·6; d = -0·2) at the end of the study in comparison with the SP group. In both groups, weight and appetite were unchanged over time without significant differences between groups. Twelve weeks of euenergetic diets with different dietary protein contents resulted in no significant weight loss in women with NWO. However, an HP diet significantly improved body composition (LBM, FM, BFP and WC) in this population.

Normal-Weight Obesity Is Associated with Increased Cardiometabolic Risk in Young Adults

Normal-weight obesity (NWO) has been shown to be associated with cardiometabolic dysfunction. However, little is known regarding this potential relationship in early adulthood. The aim of this study was to investigate the associations between NWO and cardiometabolic risk factors in a large population of Colombian young adults. A cross-sectional study was conducted on 1354 subjects (61% women), aged from 18 to 30. Anthropometric data, including body mass index (BMI) and waist circumference (WC), were estimated, and the percentage of fat mass was measured through bioelectrical impedance analysis (BIA). Muscular fitness was determined by using a handgrip strength test and normalized grip strength (NGS = handgrip (kg)/body mass (kg)). A cardiometabolic risk Z-score was derived by assessing WC, triglycerides, high-density lipoprotein cholesterol (HDL-C) cholesterol, fasting glucose, and systolic blood pressure. NWO was defined by the combination of excess %BF (over 25.5% for men and 38.9% for women) and a BMI < 25 kg/m². The overall prevalence of NWO was 29.1%. Subjects with NWO have an increased risk of cardiometabolic risk compared to the normal-weight lean group (OR = 3.10). Moreover, NWO was associated with an increased risk of presenting low HDL-C (OR = 2.34), high abdominal obesity (OR = 7.27), and low NGS (OR = 3.30), p < 0.001. There is a high prevalence of NWO in American Latin young adults and this condition is associated with an increased cardiovascular risk, high blood pressure, low HDL-C, high abdominal obesity, and low muscular strength early in life. Screening for adiposity in subjects with a normal BMI could help to identify young adults at a high risk of cardiometabolic abnormalities.

Why primary obesity is a disease?

Obesity must be considered a real pathology. In the world wide, obesity represent one of the major public health issue associated with increased morbidity and mortality. Overweight or obesity, in fact, significantly increases the risk of contracting diseases, such as: arterial hypertension, dyslipidemia, type 2 diabetes mellitus, coronary heart disease, cerebral vasculopathy, gallbladder lithiasis, arthropathy, ovarian polycytosis, sleep apnea syndrome, and some neoplasms. Despite numerous informative campaigns, unfortunately, the fight against obesity does not seem to work: in the last years, the prevalence continued to increase. The progressive and rapid increase in the incidence of obesity, which has characterized most of the economically advanced countries in the last decade, has been the main stimulus for the research of the mechanisms underlying this pathology and the related disorders. The aims of this review is to provide a revision of the literature in order to define obesity as diseases, secondly to highlight the limits and the inaccuracy of common tools used for the diagnosis of obesity, and as a third thing to strengthen the concept of the complexity of obesity as a disease among political health care providers. Obesity may be viewed as a multifactorial pathology and chronic low-grade inflammatory disease. In fact, people affected by obesity have greater risk of developing comorbility and morbility, respect to healthy. Hence, the absolute therapeutic benefit is directly proportional to the basic risk. So, internationally interest on early diagnosis of obesity is growing to avoid under- and overdiagnosis consequences. Therefore, the consequences are an aggravation of the disease and an increase in obesity related pathology like diabetes, cardiovascular disease, and cancer. The most widely used parameter for diagnosis, body mass index (BMI) is not suitable for assessing the body fat. In fact, several studies demonstrate that BMI alone cannot define obesity, which consists not so much in weight gain as in excess fat mass. The use of suitable tools for the assessment of fat mass percentage combined with clinical and genetic analysis allowed to identify different phenotypes of obesity, which explain the various paradoxes of obesity. It is essential to adopt all possible strategies to be able to combat obesity, ameliorate the suffering of patients, and reduce the social and treatment costs of obesity.

Adjustment of vascular 2-deoxy-2-[18F]fluoro-D-glucose uptake values over time through a modeling approach

To develop and test a model predicting 2-deoxy-2-[18F]fluoro-D-glucose ([18F]FDG) standardized uptake value (SUV) changes over time in the aorta and the superior vena cava (SVC). Maximum aortic SUV and mean SVC SUV were determined at two time points (T1 and T2) in the ascending (ASC), descending (DSC), abdominal (ABD) aorta, aortic arch (ARC) and SVC of patients who have undergone [18F]FDG PET/CT for clinical purposes. For SUV prediction at T2, linear and non-linear models of SUV difference for a given time change were developed in a derivation group. The results were tested in an independent validation group, whilst model reproducibility was tested in patients of the validation group who have undergone a second clinically indicated scan. Applying the linear model in the derivation group, there were no statistically significant differences in measurements obtained in the examined segments: mean differences ranged from 0 ± 0.10 in SVC to 0.01 ± 0.13 in ARC between measured and predicted SUV. In contrast, in the non-linear model, there were statistically significant differences in measurements, except in ARC, with mean differences ranging from 0.04 ± 0.14 in ARC to 0.28 ± 0.13 in ABD. In the validation group using the linear model, there were no statistically significant differences, with mean differences ranging from - 0.01 ± 0.08 in ASC to - 0.03 ± 0.11 in ABD. Regarding reproducibility, mean differences were no statistically significant, ranging from 0.004 ± 0.06 in ASC to - 0.02 ± 0.16 in ABD. We have developed a linear model allowing accurate and reproducible prediction of SUV changes over time in the aorta and SVC.

Position Paper Computational Cardiology

Computational cardiology is the scientific field devoted to the development of methodologies that enhance our mechanistic understanding, diagnosis and treatment of cardiovascular disease. In this regard, the field embraces the extraordinary pace of discovery in imaging, computational modeling, and cardiovascular informatics at the intersection of atherogenesis and vascular biology. This paper highlights existing methods, practices, and computational models and proposes new strategies to support a multidisciplinary effort in this space. We focus on the means by that to leverage and coalesce these multiple disciplines to advance translational science and computational cardiology. Analyzing the scientific trends and understanding the current needs we present our perspective for the future of cardiovascular treatment.

Prevalence and cardiometabolic risks of normal weight obesity in Chinese population: A nationwide study

BACKGROUND AND AIMS

Several studies have reported increased cardiovascular risks in normal weight obesity (NWO) populations. We aimed to investigate the prevalence of NWO and its relationships with cardiometabolic risks in Chinese patients.

METHODS AND RESULTS

The data were from the 2007-2008 China National Diabetes and Metabolic Disorders Study. The body fat (BF) was measured using the biological impedance method. NWO was defined as a normal BMI (18.5-23.9 kg/m²) but with excess BF% (BF% ≥ 24% for men and ≥33% for women). 23,748 people (9633 males and 14,115 females) were enrolled and the prevalence of NWO was 9.5% for men, 6.06% for women. The prevalence risks of diabetes (odds ratio [OR]1.519, 95% confidence interval [CI] 1.262-1.828), Framingham risk score (FRS) ≥10% (OR 1.973, 95% CI 1.596-2.439), hypertension (OR 1.525, 95% CI 1.333-1.745), and metabolic syndrome Mets (OR 2.175, 95% CI 1.920-2.463) significantly increased in the NWO group compared with the normal group. Subgroup analyses showed that, after ruling out participants with abnormal waist circumference, the male group had similar findings to the overall population; but in the female group, the prevalence risks of FRS ≥10%, hypertension, and Mets increased, although the risk of diabetes did not.

CONCLUSION

NWO is in a relatively high prevalence in Chinese population, and the prevalence of NWO is higher in Chinese men compared to Chinese women. Cardiometabolic risks significantly increase in an NWO population, and such risks persist after excluding the effect of abdominal obesity.

Association between abdominal adiposity and 20-year subsequent aortic stiffness in an initially healthy population-based cohort

BACKGROUND

Aortic stiffness is a feature of arterial aging and is associated with dismal cardiovascular prognosis. We examined whether central and general adiposity is an independent predictor of accelerated aortic stiffening 20 years later in initially healthy midlife individuals.

METHODS

Participants from the STANISLAS cohort study (826 initially healthy participants aged 30-60 from the Lorraine region in France) underwent clinical and biological measurements at baseline (1994-1995) and after ≈20 years (2011-2016). Adiposity measurements included waist circumference/BMI ratio, BMI, waist circumference, and 'body shape index' [waist circumference/(BMI height)]. Real carotid-femoral pulse wave velocity (cfPWV) was measured at end of follow-up. Our primary analysis was to test the association between waist circumference/BMI ratio and cfPWV.

RESULTS

In a multiple linear regression model adjusted for sex, age and mean arterial pressure, waist circumference -to-BMI ratio was positively associated (for 1SD increase) with higher cfPWV [regression coefficient β = 0.32, 95% confidence interval (CI) 0.19-0.45, P < 0.001]. The cfPWV was less strongly associated with body shape index (β = 0.17, 95% CI 0.022-0.32, P < 0.05) and negatively associated with BMI (-0.20, 95% CI -0.31 to -0.093, P < 0.001) and waist circumference (-0.14, 95% CI -0.28 to 0.00, P < 0.05). Sensitivity analyses demonstrated that the risk of cfPWV associated with waist circumference-to-BMI ratio remained significant after adjustment for heart rate, metabolic risk factors and inflammatory markers.

CONCLUSION

Central adiposity (and more specifically waist circumference-to-BMI ratio) is an independent predictor of 20-year subsequent aortic stiffness in initially healthy midlife subjects.

Poor Skeletal Robustness on Lower Extremities and Weak Lean Mass Development on Upper Arm and Calf: Normal Weight Obesity in Middle-School-Aged Children (9 to 12)

Background: Normal weight obesity in children has been associated with excessive body fat, lower bone density and decreased total lean mass. However, no studies have been done into whether normal weight obese children differ in skeletal robustness or lean mass development on the extremities from normal weight non-obese, overweight, and obese peers although these are important indicators of healthy development of children. Methods: Body height, body weight, BMI, four skinfolds, and two limb circumferences were assessed. We calculated total body fat using Slaughter's equations, the Frame index for skeletal robustness and muscle area for the upper arm and calf using Rolland-Cachera equations. Using national references of BMI and measured skinfolds, three subgroups of participants (9-12 years) consisting of 210 middle-school-aged children (M-age = 11.01 ± 1.05)-110 girls and 100 boys-were selected: (A) overweight obese (OWOB) (n = 72); (B) normal weight obese (NWO) (n = 69); and, (C) normal weight non-obese (NWNO) (n = 69). All values, were converted to Z-scores to take account of participant's sex and age. Results: NWO children had significantly poorer skeletal robustness on lower extremities and poorer muscle area on the upper arm and calf compared to NWNO counterparts with significantly higher evidence in boys-skeletal robustness NWO boys: Z-score = -0.85; NWO girls: Z-score = -0.43; lean mass on the calf: NWO boys Z-score = -1.34; NWO girls: Z-score = -0.85. The highest skeletal robustness-but not muscle area on the calf-was detected in OWOB children. Conclusions: Further research should focus on whether this poor skeletal and lean mass development: (1) is a consequence of insufficient physical activity regimes; (2) affects physical fitness of NWO children and could contribute to a higher prevalence of health problems in them. We have highlighted the importance of the development of a simple identification of NWO children to be used by pediatricians.

Association of body composition and eating behavior in the normal weight obese syndrome

AIM

Our aim was to identify psychological and behavioral characteristics of women affected by normal weight obese (NWO) syndrome.

METHODS

Anthropometric, body composition, eating behavior and physical activity were evaluated in 79 women.

RESULTS

48.10 % of the subjects were found to be normalweight obese (NWO), 22.79 % normalweight lean (NWL), and 29.11 % pre-obese-obese (PreOB/OB) according to BMI and body composition. Significant differences (p < 0.001) among the groups were identified on analysis of the subscales of the Eating Disorder Inventory-2 (EDI-2), suggesting progressively increased presence of psychopathology relative to body composition. In a further analysis, results of the subscales of the EDI-2 were compared with body composition parameters, revealing that BMI co-varied with body composition variables and psychological responses. %TBFat co-varied exclusively with body composition variables (height, weight, BMI, KgTBFat, and a decrease of KgTBLean (R (2) = 0.96; Q (2) = 0.94). The NWO was discriminated from PreOB/OB group (compared to BMI) only on the basis of body composition variables (R (2) = 0.68; Q (2) = 0.60).

CONCLUSION

NWO women appeared to find themselves at a cognitive crossroads, attaining intermediate scores on the EDI-2 between normal weight lean women and pre-obese or obese women, in particular in terms of drive for thinness and body dissatisfaction. The NWO syndrome not only conveys an increased risk of cardiovascular and metabolic disease, but may also significantly overlap with other eating disorders in terms of psychological symptomatology, the correct identification of which may be the key in the successful management of these patients.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01890070.

Type 2 diabetes enhances arterial uptake of choline in atherosclerotic mice: an imaging study with positron emission tomography tracer ¹⁸F-fluoromethylcholine

Background

Diabetes is a risk factor for atherosclerosis associated with oxidative stress, inflammation and cell proliferation. The purpose of this study was to evaluate arterial choline uptake and its relationship to atherosclerotic inflammation in diabetic and non-diabetic hypercholesterolemic mice.

Methods

Low-density lipoprotein-receptor deficient mice expressing only apolipoprotein B100, with or without type 2 diabetes caused by pancreatic overexpression of insulin-like growth factor II (IGF-II/LDLR^−/−ApoB^100/100 and LDLR^−/−ApoB^100/100) were studied. Distribution kinetics of choline analogue ¹⁸F-fluoromethylcholine (¹⁸F-FMCH) was assessed in vivo by positron emission tomography (PET) imaging. Then, aortic uptakes of ¹⁸F-FMCH and glucose analogue ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG), were assessed ex vivo by gamma counting and autoradiography of tissue sections. The ¹⁸F-FMCH uptake in atherosclerotic plaques was further compared with macrophage infiltration and the plasma levels of cytokines and metabolic markers.

Results

The aortas of all hypercholesterolemic mice showed large, macrophage-rich atherosclerotic plaques. The plaque burden and densities of macrophage subtypes were similar in diabetic and non-diabetic animals. The blood clearance of ¹⁸F-FMCH was rapid. Both the absolute ¹⁸F-FMCH uptake in the aorta and the aorta-to-blood uptake ratio were higher in diabetic than in non-diabetic mice. In autoradiography, the highest ¹⁸F-FMCH uptake co-localized with macrophage-rich atherosclerotic plaques. ¹⁸F-FMCH uptake in plaques correlated with levels of total cholesterol, insulin, C-peptide and leptin. In comparison with ¹⁸F-FDG, ¹⁸F-FMCH provided similar or higher plaque-to-background ratios in diabetic mice.

Conclusions

Type 2 diabetes enhances the uptake of choline that reflects inflammation in atherosclerotic plaques in mice. PET tracer ¹⁸F-FMCH is a potential tool to study vascular inflammation associated with diabetes.

Electronic supplementary material

The online version of this article (doi:10.1186/s12933-016-0340-6) contains supplementary material, which is available to authorized users.

New obesity classification criteria as a tool for bariatric surgery indication

Obesity plays relevant pathophysiological role in the development of health problems, arising as result of complex interaction of genetic, nutritional, and metabolic factors. Due to the role of adipose tissue in lipid and glucose metabolism, and low grade inflammation, it is necessary to classify obesity on the basis of body fat composition and distribution, rather than the simply increase of body weight, and the Body Mass Index. The new term of adiposopathy (‘‘sick fat’’) clearly defines the pathogenic role of adipose tissue. Four phenotypes of obese individuals have been described: (1) normal weight obese (NWO); (2) metabolically obese normal weight; (3) metabolically healthy obese; and (4) metabolically unhealthy obese or “at risk” obese. Moreover, sarcopenic obesity has been related to all the phenotypes. The category of normal weight lean, represented by metabolically healthy normal weight has been classified to distinguish from NWO. It is crucial to recommend a bariatric surgery taking into account adiposopathy and sick fat that occurs with the expansion of fat mass, changing the inflammatory and metabolic profile of the patient. Body fat percentage and genetic polymorphism have to be evaluated to personalize the best bariatric surgery intervention.

Visceral adiposity is associated with altered myocardial glucose uptake measured by (18)FDG-PET in 346 subjects with normal glucose tolerance, prediabetes, and type 2 diabetes

Background

The heart requires constant sources of energy mostly from free fatty acids (FFA) and glucose. The alteration in myocardial substrate metabolism occurs in the heart of diabetic patients, but its specific association with other metabolic variables remains unclear. We aimed to evaluate glucose uptake in hearts of subjects with normal glucose tolerance (NGT), prediabetes, and type 2 diabetes mellitus (T2DM) using [¹⁸F]-fluorodeoxyglucose-positron emission tomography (¹⁸FDG-PET) in association with visceral and subcutaneous adiposity, and metabolic laboratory parameters.

Methods

A total of 346 individuals (NGT, n = 76; prediabetes, n = 208; T2DM, n = 62) in a health promotion center of a tertiary hospital were enrolled. The fasting myocardial glucose uptake, and visceral and subcutaneous fat areas were evaluated using ¹⁸FDG-PET and abdominal computed tomography, respectively.

Results

Myocardial glucose uptake was significantly decreased in subjects with T2DM compared to the NGT or prediabetes groups (p for trend = 0.001). Multivariate linear regression analyses revealed that visceral fat area (β = −0.22, p = 0.018), fasting FFA (β = −0.39, p < 0.001), and uric acid levels (β = −0.21, p = 0.007) were independent determinants of myocardial glucose uptake. Multiple logistic analyses demonstrated that decreased myocardial glucose uptake (OR 2.32; 95 % CI 1.02–5.29, p = 0.045) and visceral fat area (OR 1.02, 95 % CI 1.01–1.03, p = 0.018) were associated with T2DM.

Conclusions

Our findings indicate visceral adiposity is strongly associated with the alteration of myocardial glucose uptake evaluated by ¹⁸FDG-PET, and its association further relates to T2DM.

The association among peri-aortic root adipose tissue, metabolic derangements and burden of atherosclerosis in asymptomatic population

AIM

To describe the relationship between a novel measurement of peri-arotic root fat and ultrasound measures of carotid artery remodeling.

MATERIALS AND METHODS

We studied 1492 consecutive subjects (mean age: 51.04 ± 8.97 years, 27% females) who underwent an annual cardiovascular risk survey in Taiwan. Peri-aortic root fat (PARF) was assessed by cardiac CT using three-dimensional (3D) volume assessment. Carotid artery morphology and remodeling were assessed by ultrasound. We explored the relationships between PARF volumes, cardiometabolic risk profiles and carotid morphology and remodeling.

RESULTS

Mean PARF volume in current study was 20.8 ± 10.6 ml. PARF was positively correlated with measures of general adiposity, systemic inflammation, and several traditional cardiometabolic risk profiles (all p < 0.001) and successfully predicted metabolic syndrome (MetS) (AUROC: 0.75, 95%, confidence interval: 0.72-0.77). Higher PARF was independently associated with increased carotid artery intima-media thickness (IMT) (β-coef.: 0.08) and diameter (β-coef.: 0.08, both p < 0.05) after accounting for age, sex, BMI and other cardiovascular risk factors. The addition of PARF beyond metabolic syndrome components significantly provided incremental prediction value for abnormal IMT (ΔAUROC: 0.053, p = 0.0021).

CONCLUSION

Peri-aortic root fat is associated with carotid IMT, even after adjustment for cardiometabolic risks, age and coronary atherosclerosis. Further research studies are warranted to identify the mediators of downstream pathophysiologic effects on carotid arteries by PARF and understand the mechanisms related to this correlation.

Normal-weight obesity is associated with increased risk of subclinical atherosclerosis

BACKGROUND

Subjects with normal body mass index (BMI) but elevated amounts of body fat (normal-weight obesity; NWO) show cardiometabolic dysregulation compared to subjects with normal BMI and normal amounts of body fat (normal-weight lean; NWL). In this study, we aimed to evaluate whether NWO individuals have higher rates of subclinical atherosclerosis compared to NWL subjects.

METHODS

From a large-scale health checkup system, we identified 2078 normal weight (18.5 ≤ BMI < 25 kg/m(2)) subjects with no previous history of coronary artery disease who underwent analysis of atherosclerosis using coronary computed tomography angiography (CCTA) and pulse wave velocity (PWV). NWO was defined as normal BMI and highest tertile of body fat percentage by sex (men ≥ 25. 4 % and women ≥ 31.4 %). CCTA was performed using a 64-detector row CT. A plaque was defined as a structure >1 mm(2) within and/or adjacent to the vessel lumen and classified according to the presence/proportion of intraplaque calcification.

RESULTS

NWO subjects (n = 283) demonstrated metabolic dysregulation compared to NWL individuals (n = 1795). After adjusting for age, sex, and smoking, NWO individuals showed higher PWV values than NWL individuals (1474.0 ± 275.4 vs. 1380.7 ± 234.3 cm/s, p = 0.006 by ANCOVA). Compared with NWL subjects, NWO subjects had a higher prevalence of soft plaques even after age, sex, and smoking adjustment (21.6% vs. 14.5%, p = 0.039 by ANCOVA). The PWV value and the log{(number of segments with plaque) + 1} showed a positive correlation with numerous parameters such as age, systolic blood pressure, visceral fat, fasting glucose level, serum triglyceride level, and C-reactive protein (CRP) in contrast to the negative correlation with high-density lipoprotein-cholesterol level. The visceral fat was an independent determinant of log{(number of segments with plaque) + 1} (ß = 0.027, SE = 0.011, p = 0.016) even after adjustment for other significant factors. Most importantly, NWO was an independent risk factor for the presence of soft plaques (odds ratio 1.460, 95 % confidence interval 1.027-2.074, p = 0.035) even after further adjustment for multiple factors associated with atherosclerosis (blood pressure, blood glucose, lipid level, CRP, medication, smoking status, physical activity).

CONCLUSIONS

NWO individuals carry a higher incidence of subclinical atherosclerosis compared with NWL individuals, regardless of other clinical risk factors for atherosclerosis.

Sex influenced association of directly measured insulin sensitivity and serum transaminase levels: Why alanine aminotransferase only predicts cardiovascular risk in men?

Background

Non alcoholic fatty liver disease (NAFLD) is an independent cardiovascular (CV) risk factor which is closely associated with insulin resistance measured by both direct or indirect methods. Gender specific findings in the relationship between alanine aminotransferase (ALT) and CV disease, the prevalence of NAFLD and type 2 diabetes (T2DM) have been published recently.

The aim of the present study was to explore the gender aspects of the association between insulin sensitivity, liver markers and other metabolic biomarkers in order to elucidate the background behind the sex influenced difference in both NAFLD, T2DM and their association with CV risk.

Patients and methods

158 female (47 normal and 111 impaired glucose intolerant) and 148 male (74 normal and 74 impaired glucose tolerant) subjects were included (mean age: 46.5 ± 8.31 vs. 41.6 ± 11.3, average Hba1c < 6.1 %, i.e. prediabetic population, drug naive at the time of the study). Subjects underwent a hyperinsulinemic normoglycemic clamp to determine muscle glucose uptake (M₃), besides liver function tests and other fasting metabolic and anthropometric parameters were determined.

Results

Significant bivariate correlations were found between clamp measured M₃ and all three liver enzymes (ALT, aspartate aminotransferase and gamma-glutamyl transferase) in both sexes. When data were adjusted for possible metabolic confounding factors correlations ceased in the male population but stayed significant in the female group. Feature selection analysis showed that ALT is an important attribute for M₃ in the female but not in male group (mean Z: 3.85 vs. 0.107). Multiple regression analysis confirmed that BMI (p < 0.0001) and ALT (p = 0.00991) significantly and independently predicted clamp measured muscle glucose uptake in women (R² = 0.5259), while in men serum fasting insulin (p = 0.0210) and leptin levels (p = 0.0294) but none of the liver enzymes were confirmed as significant independent predictors of M₃ (R² = 0.4989).

Conclusion

There is a gender specific association between insulin sensitivity, metabolic risk factors and liver transaminase levels. This might explain the sex difference in the predictive role of ALT elevation for CV disease. Moreover, ALT may be used as a simple diagnostic tool to identify insulin resistant subjects only in the female population according to our results.

A novel criterion for identifying metabolically obese but normal weight individuals using the product of triglycerides and glucose

OBJECTIVES

Metabolically obese but normal weight (MONW) individuals constitute a subgroup of normal weight individuals that display impaired insulin sensitivity with a higher risk of developing diabetes, cardiovascular disease and mortality. We aimed to propose a novel criterion for defining MONW by examining the usefulness and the cutoff value of the TyG index, a product of the levels of triglycerides and glucose, in identifying MONW individuals. In addition, the performance of this criterion in predicting the future incidence of diabetes was assessed.

SUBJECTS/METHODS

A total of 7541 non-diabetic, normal weight (body mass index ⩾18.5 and <25 kg m(-)(2)) subjects were selected from the Korea National Health and Nutrition Examination Survey conducted in 2009-2010. Another 3185 participants with follow-up studies were selected from a prospective community-based cohort study. The TyG index was calculated as ln(fasting triglycerides (mg dl(-1)) × fasting glucose (mg dl(-1))/2).

RESULTS

The levels of the TyG index paralleled the prevalence of metabolic syndrome and its components. The cutoff value of the TyG index that reflected MONW based on the receiver operating characteristics analysis was 8.82 for men and 8.73 for women, with the area under the curve values being 0.855 and 0.868, respectively. The sensitivity and the specificity were 84.2 and 77.6% in men and 69.1 and 89.4% in women, respectively. Individuals designated as MONW, who have a normal weight and TyG levels higher than cutoff, displayed a metabolically unhealthy phenotype and an approximately twofold higher risk of developing diabetes compared with metabolically healthy normal weight subjects.

CONCLUSIONS

We propose a simple diagnostic criterion of MONW, which might be used to discriminate subjects with a higher risk of metabolic diseases.

Inflammation, Atherosclerosis, and Coronary Artery Disease: PET/CT for the Evaluation of Atherosclerosis and Inflammation

Atherosclerosis is a prevalent cardiovascular disease marked by inflammation and the formation of plaque within arterial walls. As the disease progresses, there is an increased risk of major cardiovascular events. Owing to the nature of atherosclerosis, it is imperative to develop methods to further understand the physiological implications and progression of the disease. The combination of positron emission tomography (PET)/computed tomography (CT) has proven to be promising for the evaluation of atherosclerotic plaques and inflammation within the vessel walls. The utilization of the radiopharmaceutical tracer, 18F-fluorodeoxyglucose (¹⁸F-FDG), with PET/CT is invaluable in understanding the pathophysiological state involved in atherosclerosis. In this review, we will discuss the use of ¹⁸F-FDG-PET/CT imaging for the evaluation of atherosclerosis and inflammation both in preclinical and clinical studies. The potential of more specific novel tracers will be discussed. Finally, we will touch on the potential benefits of using the newly introduced combined PET/magnetic resonance imaging (MRI) for non-invasive imaging of atherosclerosis.

PET imaging of atherosclerosis

ABSTRACT 

Atherosclerosis is a chronic, progressive, multifocal disease of the arterial wall, which is mainly fuelled by local and systemic inflammation, often resulting in acute ischemic events following plaque rupture and vessel occlusion. When assessing the cardiovascular risk of an individual patient, we must consider both global measures of disease activity and local features of plaque vulnerability, in addition to anatomical distribution and degree of established atherosclerosis. These parameters cannot be measured with conventional anatomical imaging techniques alone, which are designed primarily to identify the presence of organic intraluminal obstruction in symptomatic patients. However, molecular imaging with PET, using specifically targeted radiolabeled probes to track active in vivo atherosclerotic mechanisms noninvasively, may potentially provide a method that is better suited for this purpose. Vascular PET imaging can help us to further understand aspects of plaque biology, and current evidence supports a future role as an emerging clinical tool for the quantification of cardiovascular risk in order to guide and monitor responses to antiatherosclerosis treatments and to distinguish high-risk plaques.

Obesity: pathophysiology and intervention

Obesity presents a major health hazard of the 21st century. It promotes co-morbid diseases such as heart disease, type 2 diabetes, obstructive sleep apnea, certain types of cancer, and osteoarthritis. Excessive energy intake, physical inactivity, and genetic susceptibility are main causal factors for obesity, while gene mutations, endocrine disorders, medication, or psychiatric illnesses may be underlying causes in some cases. The development and maintenance of obesity may involve central pathophysiological mechanisms such as impaired brain circuit regulation and neuroendocrine hormone dysfunction. Dieting and physical exercise offer the mainstays of obesity treatment, and anti-obesity drugs may be taken in conjunction to reduce appetite or fat absorption. Bariatric surgeries may be performed in overtly obese patients to lessen stomach volume and nutrient absorption, and induce faster satiety. This review provides a summary of literature on the pathophysiological studies of obesity and discusses relevant therapeutic strategies for managing obesity.

Imaging of atherosclerotic plaques in obesity: excessive fat accumulation, plaque progression and vulnerability

Obesity is becoming a major health issue in the world due to sedentary lifestyles and increasing intake of Western diets. Obesity is associated with metabolic abnormalities and atherosclerotic cardiovascular diseases. Adipose tissue has been increasingly considered to play a critical role in inducing metabolic disturbances and promoting atherogenesis. Arterial wall imaging permits direct visualization of atheroma burden in various vascular beds. In addition, recent advances in imaging technology help characterize components, microstructures and functional features of atherosclerotic plaques. These imaging modalities have contributed to elucidating factors associated with atherosclerosis in obese patients. Also, it provides opportunities to evaluate the effect of novel therapies on plaques in the setting of obesity. The findings of recent imaging studies and the clinical implications will be reviewed.

Individually tailored screening of susceptibility to sarcopenia using p53 codon 72 polymorphism, phenotypes, and conventional risk factors

BACKGROUND AND AIM

p53 activity plays a role in muscle homeostasis and skeletal muscle differentiation; all pathways that lead to sarcopenia are related to p53 activities. We investigate the allelic frequency of the TP53 codon 72 in exon 4 polymorphism in the Italian female population and the association with appendicular skeletal muscle mass index in normal weight (NW), normal weight obese (NWO), and preobese-obese (Preob-Ob) subjects.

METHODS

We evaluated anthropometry, body composition, and p53 polymorphism in 140 women distinguished in NW, NWO, and Preob-Ob.

RESULTS

*Arg/*Arg genotype increases sarcopenia risk up to 20% (*Arg/*Arg genotype OR = 1.20; 95% CI = 0.48-2.9; *proallele carriers OR = 0.83; 95% CI = 0.83-2.06). The risk of being sarcopenic for *Arg/*Arg genotype in NWO and Preob-Ob is 31% higher than NW carriers of *proallele (RR = 0,31, 95% CI = 0,15-0,66, P = 0,0079). We developed a model able to predict sarcopenia risk based on age, body fat, and p53 polymorphism.

CONCLUSION

Our study evidences that genotyping TP53 polymorphism could be a useful new genetic approach, in association with body composition evaluations, to assess sarcopenia risk.