Body fat percentage cutoffs for risk of cardiometabolic abnormalities in the Chinese adult population: a nationwide study

Primary and residual cardiometabolic risk factors among young adults in a Russian city

BACKGROUND

Cardiovascular diseases are a leading cause of mortality and a significant contributor to temporary and permanent disabilities worldwide. This study aimed to investigate the burden of primary and residual cardiometabolic risk factors in a sample of young adults in the Russian city of Kazan.

METHODS

This case-control study used the Cardiometabolic Disease Staging (CMDS) classification system, which has been validated in several countries. The study included 191 individuals aged 25-44 years who met the inclusion criteria but did not meet any exclusion criteria. Data collection involved a patient card with questions from the World Health Organization's STEPS instrument, face-to-face patient interviews, and a physical examination. Anthropometric assessments included height, weight, and waist circumference measurements. Body composition was evaluated using bioelectrical impedance measurements. Patients also underwent in-depth laboratory biochemical analyses.

RESULTS

The study cohort was comprised of 97 females (50.8%) and 94 males (49.2%). The median age of participants was 35.00 years [IQR: 30.00-39.00]. The study cohort showed an increase in all anthropometric parameters, with abdominal obesity and overweight reaching 100% in the CMDS 3. Apart from atherogenic lipids and raised blood pressure, other risk factors that precipitate residual risk and were not part of CMDS, such as insulin levels, insulin resistance, leptin values, and hyperuricemia, increased as CMDS levels increased.

CONCLUSIONS

The prevalence of cardiometabolic risk factors was high in young adults in Kazan. This study highlights the need for the early identification and management of cardiometabolic risk factors in young adults to prevent the development of cardiovascular diseases later in life.

Distribution of daily protein intake and appendicular skeletal muscle mass in healthy free-living Chinese older adults

AIMS

Evidence regarding impact of protein intake distribution on skeletal muscle mass in older adults is limited and inconsistent. This study aims to investigate the relationship of evenness of dietary protein distribution and number of meals exceeding a threshold with appendicular skeletal muscle mass (ASM) in healthy and free-living Chinese older adults.

METHODS

Repeated measured data of 5689 adult participants aged ≥ 60 years from the China Health and Nutrition Survey (CHNS) 2015 and 2018 waves were analyzed. Mixed-effects linear regression model was performed to examine the relationship between coefficient of variance (CV) of protein intake across meals, number of meals ≥ 0.4 g protein/kg BW and ASM, respectively. Analyses were conducted separately for male and female.

RESULTS

The average CV of protein intake in each wave was in the range of 0.34-0.35. More than 40% male and female participants in each wave had no meal reaching 0.4 g protein/kg BW. Female participants in the highest quartile of protein intake CV had significantly lower ASM (β = -0.18, 95%CI = -0.32, -0.04) compared with those in the lowest quartile, after adjustment for multiple confounders. Significant negative trends were observed across dietary protein CV quartiles with ASM both in male (P trend = 0.043) and female (P trend = 0.007). Significant positive association between number of meals exceeding 0.4 g protein /kg BW and relative ASM were observed in females (2 meals vs. 0 meal: β = 0.003, 95%CI = 0.0007,0.006;≥3 meals vs. 0 meal: β = 0.008, 95%CI = 0.003,0.013), after adjusting for multiple covariates.

CONCLUSIONS

A more even-distributed protein intake pattern and more meals reaching protein intake threshold were respectively associated with higher appendicular skeletal muscle mass in healthy and free-living older Chinese adults. Prospective studies and intervention trials are needed to confirm these cross-sectional findings.

Longitudinal relationship between body fat percentage and risk of type 2 diabetes in Chinese adults: Evidence from the China Health and Nutrition Survey

Objective

Body fat percentage (BF%) might be an alternative index of obesity which is the major risk factor for developing type 2 diabetes (T2D). We aim to longitudinally evaluated the relationship between BF% and risk of T2D.

Methods

A sample of 5,595 adults aged 18-65 who participated in two waves of China Health and Nutrition Survey (CHNS 2015 and 2018) was analyzed. Two level mixed-effects modified Poisson regression with robust estimation of variance stratified by sex was used to evaluate the risk ratios (RRs) for T2D according to quintiles of BF%, and the curves of receiver operating characteristic (ROC) were plotted to identify the optimal total and trunk BF% cut-off points for predicting an increased T2D risk.

Results

In males, compared with subjects in the first quintile of total BF%, those in the third (RR = 2.03, 95% CI 1.09-3.79), fourth (RR = 2.56, 95%CI 1.46-4.48), and fifth (RR = 2.16, 95%CI 1.22-3.82) quintile had higher risk of T2D after adjusting for all potential confounders (p-trend < 0.001). For females, the RR (95% CI) was 1.92 (1.14, 3.24) in the fifth quintile (p-trend = 0.014). Males and females with a trunk BF% >25.5 and 34.4% (≥ quintile 4), respectively, were at significantly increased risk of T2D (p-trend = 0.001). Besides, the optimal cut-off values of total and trunk BF% were 21.9 and 25.2% for males, and 36.7 and 30.3% for females, respectively.

Conclusions

The incident risk of T2D significantly increased over specific level of total and trunk BF% in both Chinese males and females, and the optimal BF% cut-off values were valuable for clinical application of BF% based on sex difference, which may be a cost-effective implementation for prevention and treatment of T2D in China.

Using noninvasive anthropometric indices to develop and validate a predictive model for metabolic syndrome in Chinese adults: a nationwide study

PURPOSE

Metabolic syndrome (Mets) is a pathological condition that includes many abnormal metabolic components and requires a simple detection method for rapid use in a large population. The aim of the study was to develop a diagnostic model for Mets in a Chinese population with noninvasive anthropometric and demographic predictors.

PATIENTS AND METHODS

Least absolute shrinkage and selection operator (LASSO) regression was used to screen predictors. A large sample from the China National Diabetes and Metabolic Disorders Survey (CNDMDS) was used to develop the model with logistic regression, and internal, internal-external and external validation were conducted to evaluate the model performance. A score calculator was developed to display the final model.

RESULTS

We evaluated the discrimination and calibration of the model by receiver operator characteristic (ROC) curves and calibration curve analysis. The area under the ROC curves (AUCs) and the Brier score of the original model were 0.88 and 0.122, respectively. The mean AUCs and the mean Brier score of 10-fold cross validation were 0.879 and 0.122, respectively. The mean AUCs and the mean Brier score of internal-external validation were 0.878 and 0.121, respectively. The AUCs and Brier score of external validation were 0.862 and 0.133, respectively.

CONCLUSIONS

The model developed in this study has good discrimination and calibration performance. Its stability was proved by internal validation, external validation and internal-external validation. Then, this model has been displayed by a calculator which can exhibit the specific predictive probability for easy use in Chinese population.

Obesity parameters in relation to lung function levels in a large Chinese rural adult population

OBJECTIVES

The association between obesity parameters and lung function indicators in the general Chinese rural adult population remains unclear.

METHODS

In total, 8,284 Chinese adults aged 20 years to 80 years old from Xinxiang were recruited. Obesity-related parameters, including body mass index (BMI), waist circumference (WC), hip circumference (HC), waist-to-hip ratio (WHR), waistto-height ratio (WHtR), body fat percentage (BFP), basal metabolism, and visceral fat index, and lung function parameters such as forced vital capacity and forced expiratory volume in first second were measured.

RESULTS

The total prevalence of obesity defined by BMI, WC, WHR, WHtR, and BFP was 23.2%, 58.2%, 66.7%, 69.2%, and 56.5%, respectively. Spearman correlation analyses showed significant correlations between all obesity-related parameters and lung function. Linear regression analyses further demonstrated that BMI, WHtR, BFP, and general obesity defined using those indicators were negatively associated with lung function, while WC, WHR, and central obesity defined accordingly were positively associated with lung function. The relationship between general obesity and lung function was more evident in women than in men, while the link between central obesity and lung function was more obvious in men than in women.

CONCLUSIONS

Obesity is closely related to lung function in the general Chinese adult population. Weight control and loss are important strategies to improve lung function and respiratory health.

Anthropometric Indicators as a Tool for Diagnosis of Obesity and Other Health Risk Factors: A Literature Review

Obesity is characterized by the accumulation of an excessive amount of fat mass (FM) in the adipose tissue, subcutaneous, or inside certain organs. The risk does not lie so much in the amount of fat accumulated as in its distribution. Abdominal obesity (central or visceral) is an important risk factor for cardiovascular diseases, diabetes, and cancer, having an important role in the so-called metabolic syndrome. Therefore, it is necessary to prevent, detect, and appropriately treat obesity. The diagnosis is based on anthropometric indices that have been associated with adiposity and its distribution. Indices themselves, or a combination of some of them, conform to a big picture with different values to establish risk. Anthropometric indices can be used for risk identification, intervention, or impact evaluation on nutritional status or health; therefore, they will be called anthropometric health indicators (AHIs). We have found 17 AHIs that can be obtained or estimated from 3D human shapes, being a noninvasive alternative compared to X-ray-based systems, and more accessible than high-cost equipment. A literature review has been conducted to analyze the following information for each indicator: definition; main calculation or obtaining methods used; health aspects associated with the indicator (among others, obesity, metabolic syndrome, or diabetes); criteria to classify the population by means of percentiles or cutoff points, and based on variables such as sex, age, ethnicity, or geographic area, and limitations.

Trunk fat volume can be a predictor of postoperative complications after gastrectomy: a retrospective cohort study

Background

Obesity can affect postoperative outcomes of gastrectomy. Visceral fat area is superior to body mass index in predicting postoperative complications. However, visceral fat area measurement is time-consuming and is not optimum for clinical use. Meanwhile, trunk fat volume (TFV) can be easily measured via bioelectrical impedance analysis. Hence, the current study aimed to determine the ability of TFV to predict the occurrence of complications after gastrectomy.

Methods

We retrospectively reviewed patients who underwent curative gastrectomy for gastric cancer between November 2016 and November 2019. The trunk fat volume-to-the ideal amount (%TFV) ratio was obtained using InBody 770 before surgery. The patients were classified into the obese and nonobese groups according to %TFV (TFV-H group, ≥ 150%; TFV-L group, < 150%) and body mass index (BMI-H group, ≥ 25 kg/m²; BMI-L group, < 25 kg/m²). We compared the short-term postoperative outcomes (e.g., operative time, blood loss volume, number of resected lymph nodes, and duration of hospital stay) between the obese and nonobese patients. Risk factors for complications were assessed using logistic regression analysis.

Results

In total, 232 patients were included in this study. The TFV-H and BMI-H groups had a significantly longer operative time than the TFV-L (p = 0.022) and BMI-L groups (p = 0.006). Moreover, the TFV-H group had a significantly higher complication rate (p = 0.004) and a lower number of resected lymph nodes (p < 0.001) than the TFV-L group. In the univariate analysis, %TFV ≥ 150, total or proximal gastrectomy, and open gastrectomy were found to be potentially associated with higher complication rates (p < 0.1 for all). Moreover, the multivariate analysis revealed that %TFV ≥ 150 (OR: 2.73; 95% CI: 1.37–5.46; p = 0.005) and total or proximal gastrectomy (OR: 3.57; 95% CI: 1.79–7.12; p < 0.001) were independently correlated with postoperative morbidity.

Conclusions

%TFV independently affected postoperative complications. Hence, it may be a useful parameter for the evaluation of obesity and a predictor of complications after gastrectomy.

Normal weight obesity and the risk of diabetes in Chinese people: a 9-year population-based cohort study

We evaluated the risk of developing diabetes in Chinese individuals with normal weight obesity (NWO). This 9-year population-based cohort study was based on the China National Diabetes and Metabolic Disorders Survey. A total of 1128 subjects without diabetes were included. Body fat percentage (BF%) was assessed by electrical bioimpedance. NWO was defined as subjects with a normal BMI (< 24 kg/m²) and an excess BF% (≥ 24% in men; ≥ 33% in women). Of 1128 individuals, 528 individuals were normal weight non-obese (NWNO), 118 (10.5%) were normal weight obese (NWO), 63 were overweight non-obese (OWNO), and 419 were overweight obese (OWO). During a follow-up of 9.0 years (interquartile range: 8.9–9.3), 113 (10.0%) individuals developed diabetes. The incidence rates of diabetes in NWNO, NWO, OWNO and OWO people were 5.69 (27 cases), 11.30 (12 cases), 3.53 (2 cases) and 19.09 (72 cases) per 1000 person-years, respectively. Cox regression analyses indicated multivariate-adjusted hazard ratios of diabetes in NWO, OWNO and OWO people were 2.110 (95% CI 1.026–4.337, p = 0.025), 0.441 (95% CI 0.101–1.928, p = 0.232) and 3.465 (95% CI 2.163–5.551, p < 0.001), respectively, relative to NWNO people. Chinese people with NWO are at increased risk of developing diabetes. We strongly suggest the incorporation of BF% measurement into the regular physical examination in Chinese medical practice.

Optimal cut-off values for anthropometric measures of obesity in screening for cardiometabolic disorders in adults

Excessive accumulation of body fat (BF) promotes obesity, whilst posing a significant health hazard. There being no agreed, optimal quantifying methods, application of BF variable in clinical practice is not deemed an effective assessment option. The study, involving 4,735 patients (33.6% men), aged 45-64, aimed to identify optimal cut-off values for anthropometric indicators of obesity to evaluate cardiometabolic risk. A minimum P-value approach was applied to calculate the cut-offs for BF%. Threshold values for body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR), and waist-to-height (WHTR) ratio, facilitating optimal differentiation of cardiometabolic risk, were based on BF%, expressed as a binary classifier. The newly estimated cut-off values for predicting cardiometabolic risk, based on BMI, were lower than the referential obesity thresholds, whereas the threshold values of WC, WHR, and WHTR were higher. Apart from dyslipidemia, the odds of cardiometabolic disorders were higher, when the anthropometric indicators under study exceeded the cut-off points in both sexes. The proposed cut-offs proved instrumental in predicting cardiometabolic risk, whilst highlighting diagnostic and clinical potential of BF%, whereas BMI boasted the highest predictive potential. Cardiometabolic risk also proved significantly higher even in the overweight patients.

Usefulness of relative fat mass in estimating body adiposity in Korean adult population

Various indicators have been suggested as replacements of body mass index (BMI) for estimating body fat percentage, including the recently introduced relative fat mass (RFM). However, RFM has not been assessed in different ethnicities; therefore, we evaluated whether RFM can be used to estimate body fat percentage in Korean adults and whether RFM is a useful indicator of obesity. Based on the Korea National Health and Nutrition Examination Survey (KNHANES) 2008-2011, we analyzed a total of 18,706 individuals (7,970 men, 10,643 women) aged ≥20 years who underwent dual-energy X-ray absorptiometry. We compared obesity (body fat ≥25% for men, 35% for women) misclassification rate of RFM (≥25 for men, 35 for women) and BMI (≥25 kg/m²). Diagnostic accuracy and optimal cut-offs of BMI and RFM were verified by comparing area under the receiver operating characteristic curve (AUC). RFM and BMI misclassification rates were similar obesity diagnosis based on body fat percentage (27.9% vs. 27.8%) among men. RFM misclassification rate was lower than that of BMI (22% vs. 45%) in women. AUC of RFM was higher in men (AUC: 0.79 vs. 0.78; p = 0.004) and lower in women (AUC: 0.80 vs. 0.83) than those of BMI (p < 0.001). In this study, RFM showed diagnostic accuracy for detecting excess body fat percentage, comparable to that of BMI. Using RFM with BMI could be beneficial in improving the diagnostic accuracy of obesity assessment in women.

Fasting triglycerides and glucose index is more suitable for the identification of metabolically unhealthy individuals in the Chinese adult population: A nationwide study

AIMS/INTRODUCTION

Metabolic unhealth can be defined by the components of metabolic syndrome, which is closely connected to insulin resistance. We aimed to determine a simple index to identify metabolic unhealth in the Chinese adult population.

MATERIALS AND METHODS

A total of 30,291 individuals were screened from the China National Diabetes and Metabolic Disorders Study carried out from June 2007 to May 2008. Metabolic unhealth was defined using components of metabolic syndrome, except waist circumference. We compared the three surrogate indices of insulin resistance: the product of fasting triglycerides and glucose (TyG), triglycerides divided by high-density lipoprotein cholesterol and the metabolic score for insulin resistance for the evaluation of metabolic status.

RESULTS

All indices had high sensitivity and specificity for the identification of metabolic unhealth, especially the TyG index with an area under the curve of 0.863 for men and 0.867 for women. Participants were divided into subgroups for further analysis. The TyG index also showed high diagnostic values, especially for younger individuals and men with normal waist circumference. Sex-specific cut-offs for three indices were also used to define metabolic unhealth. The TyG index showed the highest agreement with κ values of 0.603 and 0.605 for men and women between the components of metabolic syndrome and three indices.

CONCLUSIONS

We propose that the TyG index, just read in one blood laboratory test report, is simpler and more suitable for the identification of metabolically unhealthy individuals as well as who have high risk of cardiometabolic diseases of the Chinese adult population.

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.