Neck Circumference Is Independently Associated with Cardiometabolic Risk Factors: Cross-Sectional Analysis from ELSA-Brasil

Neck Circumference Cut-Off Points for Identifying Adiposity: Association with Chronic Metabolic Diseases in Older People

BACKGROUND

The leading cause of death in older people is cardiovascular diseases. Several studies have found that neck circumference (NC) is a simple anthropometric marker associated with adiposity. The aim of this study is to estimate and validate NC cut-off points as adiposity markers and analyze their association with cardiovascular and chronic metabolic diseases in older people.

METHODS

A cross-sectional study in 358 non-disabled, community-dwelling older people (71.7 ± 3.9 years) living in Santiago de Chile and participating in the HTSMayor study was conducted. Measurements of body composition and cardiovascular risks were evaluated. Receiver operating characteristic (ROC) curves and multiple logistic regression models were used to evaluate the association of NC with cardiovascular and chronic metabolic diseases. NC cut-off points were obtained to predict obesity, abdominal obesity, and adiposity.

RESULTS

The best performance values of neck circumference relative to obesity and adiposity were obtained with respect to abdominal obesity (40.6 cm in men and 34.2 cm in women). Higher NC values were associated with a higher area under the curve (AUC) for men and women (men: AUC = 0.84; women: AUC = 0.86). NC was significantly associated with a higher risk for diabetes mellitus (OR = 1.95), hypertension (OR = 2.42), acute myocardial infarction (OR = 4.36), and comorbidities (OR = 2.01), and a lower risk for sarcopenia (OR = 0.35).

CONCLUSIONS

This study shows that NC is a useful tool for detecting abdominal obesity, obesity, and adiposity in older people and that a higher NC increases the risk of chronic diseases.

Anthropometric indexes for predicting high blood pressure in Turkish adults

Purpose

It is controversial which anthropometric indexes are the best in predicting the risk of hypertension and how anthropometric measurements are related to blood pressure (BP). This study aimed to evaluate the relationship between BP and anthropometric indexes and to determine the best predictors for hypertension risk.

Methods

This cross-sectional study was conducted with 415 consecutive participants (161 men, mean age: 33.4 years) aged 18-88 years in Istanbul, Turkey. Weight, height, waist circumference (WC), and neck circumference (NC) and BP were measured by well-trained personnel. Waist-to-height ratio (WHtR) and body mass index (BMI) were calculated. Pearson correlation, linear regression, and multivariate analyses were used to assess the relationship between anthropometric measurements and SBP, DBP, using the Statistical Package for the Social Sciences version 23.0.

Results

The systolic BP (SBP) and diastolic BP (DBP) were related to weight, WC, NC, BMI, and WHtR (P < 0.05). Linear regression analyses showed BMI and WC as independent risk factors for SBP with an increase by 1.11 mmHg in men (P = 0.036) and 1.59 mmHg in women (P = 0.001) in SBP when BMI increased 1 unit, while SBP increases by 0.2 mmHg when WC increases by 1 unit regardless of gender (P = 0.013).

Conclusion

Our results showed that BMI and WC are related to BP and important predictors of hypertension risk. Therefore, the uses of BMI and WC are recommended as screening tools for the prediction of hypertension risk among Turkish adults.

Neck circumference as a predictor of cardiometabolic risk and truncal obesity in people living with HIV

Introduction

Introduction: recent studies have suggested the use of neck circumference as a parameter capable of identifying risks of cardiometabolic complications and the accumulation of truncal fat caused by both antiretroviral therapy and the lifestyle of people with the human immunodeficiency virus (HIV). Objective: to investigate the relationship between neck circumference and anthropometric indicators and to assess cardiometabolic risk and truncal obesity through proposed cut-off points. Methods: cross-sectional study including 233 people with HIV. Demographic, socioeconomic, lifestyle and clinical data were collected using a structured questionnaire. The anthropometric evaluation included: weight, height, body mass index (BMI) measurements; waist (WC), neck (NC), arm and arm muscle circumferences; triceps and subscapular skinfolds and their sum. ROC curves were constructed to determine the accuracy of NC in predicting cardiometabolic risk in people living with HIV. Results: the sample was 57.5 % male, with a mean age of 38.4 years (95 %CI: 37.2-39.7 years). NC showed a positive and significant correlation with all anthropometric variables analyzed (p < 0.05), and a higher correlation strength with WC and BMI. The NC cut-off point selected as a predictor of risk of cardiac metabolic complications and truncal obesity in women was ≥ 32.4 cm, considering both WC and BMI. For men, the NC cut-off points were different when considering WC (≥ 39.6 cm) and BMI (≥ 38.1 cm) as a reference. It is worth noting that NC performed well in ROC curve analysis for men, while in women it was a poor performance. Conclusion: NC proved to be a promising indicator in the assessment of nutrition and health of people living with HIV, especially in men.

Evaluating Neck Circumference as an Independent Predictor of Metabolic Syndrome and Its Components Among Adults: A Population-Based Study

Background Metabolic syndrome (MetS), a public health problem worldwide, represents a high-risk condition for cardiovascular disease and diabetes. The reserve of subcutaneous fat in the upper torso is an important factor in the development of MetS and its risk factors. As neck circumference (NC) is a simple and reliable index that indicates upper-body subcutaneous fat accumulation, this study was conducted to investigate the association between NC with MetS and its components in a large population-based sample of Iranian adults. Methods The present cross-sectional study was conducted among 2094 individuals aged 20-70 years from Yazd Health Study (YaHS). MetS was defined based on the National Cholesterol Education Program Adult Treatment Panel III (ATP III) criteria. NC more than 40.25 cm for men and more than 35.75 cm for women was considered a high-risk NC. Logistic regression analysis was applied to obtain the associations of NC with MetS and its component. Results After adjusting for age, BMI, energy intake, physical activity, and smoking in those whose NC was higher than normal, the risk of the MetS (odds ratio {OR}: 2.32; 95%CI: 1.55-3.46, P<0.001 in men and OR: 2.56; 95%CI: 1.76-3.74, P<0.001 in women), abdominal obesity (OR: 4.39; 95%CI: 2.67-7.23, P<0.001 in men and OR: 1.92; 95%CI: 1.27-2.90, P=0.002 in women), high blood pressure (OR: 1.54; 95%CI: 1.07-2.21, P=0.02 in men and OR: 1.51; 95%CI: 1.06-2.14, P=0.02 in women), low high-density lipoprotein cholesterol (HDL-C) (OR: 1.47; 95%CI: 1.01-2.15, P=0.04 in men and OR: 1.69; 95%CI: 1.23-2.32, P=0.001 in women), and hypertriglyceridemia (OR: 1.41; 95%CI: 1.03-1.99, P=0.04 in men and OR: 1.68; 95%CI: 1.17-2.41, P=0.005 in women) were higher. There was no significant difference in the risk of hyperglycemia between the two NC groups in both sexes. The Pearson's correlation coefficients of NC with waist circumference, hip circumference, body mass index, and waist-to-height ratio were 0.52, 0.43, 0.41, and 0.31, respectively (P<0.001). Moreover, NC had a considerable correlation with serum triglyceride, high-density lipoprotein, systolic blood pressure, and diastolic blood pressure (0.27, -0.30, 0.29, 0.25, P<0.001), respectively. Conclusion Increased NC was significantly associated with higher odds of MetS and its components. Since NC measurement is simple, inexpensive, reliable, and less invasive, it can be used as a complementary tool in the screening and diagnosis of MetS and its risk factors in clinical and community programs especially in developing countries.

RELATIONSHIP BETWEEN SELENIUM NUTRITIONAL STATUS AND MARKERS OF LOW-GRADE CHRONIC INFLAMMATION IN OBESE WOMEN

Low-grade chronic inflammation is one of the main disorders that characterize adipose tissue dysfunction in obesity and is an important element in the pathogenesis of several comorbidities. In this context, selenium is an essential micronutrient that exerts important anti-inflammatory functions, and the role of selenium in controlling inflammation associated with obesity is not well defined. Thus, this study aimed to evaluate the relationship between markers of the nutritional status of selenium and low-grade chronic inflammation in obese women. This cross-sectional study included 81 women aged between 18 and 50 years, who were divided into two groups according to body mass index (BMI): the obesity group (n = 38) and normal weight group (n = 43). Selenium intake was assessed by 3-day diet records. The plasma, erythrocyte, and urinary selenium concentrations were determined using inductively coupled plasma optical emission spectrometry. The analysis of serum cytokines interleukin (IL)-8, IL-1β, IL-6, IL-10, and tumor necrosis factor alpha (TNFα) was performed using flow cytometry. The results of this study revealed that the obese women had higher dietary intake of selenium than eutrophic women. However, obese participants showed decreased selenium concentrations in plasma and erythrocytes, in parallel with increased concentrations of selenium in the urine. Regarding the inflammatory parameters, obese women exhibited higher concentrations of IL-6 and lower concentrations of the cytokines IL-8, IL-1β, and TNFα than eutrophic women. In the binary logistic regression analysis, erythrocyte selenium was considered an independent predictor of the serum concentrations of cytokine IL-8 in obese women, reflecting the anti-inflammatory action of this micronutrient.

Towards Development of Specular Reflection Vascular Imaging

Specular reflection from tissue is typically considered as undesirable, and managed through device design. However, we believe that specular reflection is an untapped light-tissue interaction, which can be used for imaging subcutaneous blood flow. To illustrate the concept of subcutaneous blood flow visualization using specular reflection from the skin, we have developed a ray tracing for the neck and identified conditions under which useful data can be collected. Based on our model, we have developed a prototype Specular Reflection Vascular Imaging (SRVI) device and demonstrated its feasibility by imaging major neck vessels in a case study. The system consists of a video camera that captures a video from a target area illuminated by a rectangular LED source. We extracted the SRVI signal from 5 × 5 pixels areas (local SRVI signal). The correlations of local SRVIs to the SRVI extracted from all pixels in the target area do not appear to be randomly distributed, but rather form cohesive sub-regions with distinct boundaries. The obtained waveforms were compared with the ECG signal. Based on the time delays with respect to the ECG signal, as well as the waveforms themselves, the sub-regions can be attributed to the jugular vein and carotid artery. The proposed method, SRVI, has the potential to contribute to extraction of the diagnostic information that the jugular venous pulse can provide.

Association between neck circumference and non-alcoholic fatty liver disease: cross-sectional analysis from ELSA-Brasil

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) has become a public health problem worldwide. Neck circumference (NC) is a simple anthropometric adiposity parameter that has been correlated with cardiometabolic disorders like NAFLD.

OBJECTIVES

To investigate the association between NC and NAFLD, considering their obesity-modifying effect, among participants from the Longitudinal Study of Adult Health (ELSA-Brasil) baseline study.

DESIGN AND SETTINGS

Cross-sectional study at the ELSA-Brasil centers of six public research institutions.

METHODS

This analysis was conducted on 5,187 women and 4,270 men of mean age 51.8 (± 9.2) years. Anthropometric indexes (NC, waist circumference [WC] and body mass index [BMI]), biochemical and clinical parameters (diabetes, hypertension and dyslipidemia) and hepatic ultrasound were measured. The association between NC and NAFLD was estimated using multinomial logistic regression, considering potential confounding effects (age, WC, diabetes, hypertension and dyslipidemia). Effect modification was investigated by including the interaction term NC x BMI in the final model.

RESULTS

The frequency of NAFLD and mean value of NC were 33.6% and 33.9 (± 2.5) cm in women, and 45.8% and 39.4 (± 2.8) cm in men, respectively. Even after all adjustments, larger NC was associated with a greater chance of moderate/severe NAFLD (1.16; 95% confidence interval [CI] for women; 1.05, 95% CI for men; P < 0.001). Presence of multiplicative interaction between NC and BMI (P < 0.001) was also observed.

CONCLUSION

NC was positively associated with NAFLD in both sexes, regardless of traditional adiposity indexes such as BMI and WC. The magnitude of the association was more pronounced among women.

Correlation between Neck Circumference and Other Anthropometric Measurements in Eight Latin American Countries. Results from ELANS Study

Neck circumference (NC) is being used to identify the risk of chronic diseases. There is a high prevalence of overweight and obesity in Latin America, and neck circumference is a simple and practical measurement to assess this, especially in primary health centers. We analyzed the correlation between the NC anthropometric indicator and other anthropometric measurements such as BMI and waist circumference (WC) in eight Latin American cities. We applied Pearson's correlation to identify the correlate NC with the other anthropometric variables stratified by sex; the sensitivity (Se) and specificity (Sp) by sex were evaluated according to the cut-off established with the Youden Index. The strongest correlations between NC and WC were found when stratified by sex (women: r = 0.71; men: r = 0.69, respectively) followed by the correlation between NC and BMI (r = 0.65, both sex). NC cut-off points of 39.0 cm in men and 32.9 cm in women identified those individuals with an increased WC and 39.8 and 33.7 cm, respectively, for a substantial increase in WC. For BMI ≥ 25.0 kg/m² for men, the cut-off point was 37.5 cm, and for women, it was 33.1 cm, and for BMI ≥ 30 kg/m², the cut-off points were 39.2 and 34.2 cm, for men and women, respectively. Conclusion: NC proved to be a useful, practical, and inexpensive tool that can be used to identify, evaluate, and monitor overweight and obese individuals.

Neck circumference as a marker of body adiposity in young to middle-aged adults

OBJECTIVE

Neck circumference (NC) is a straightforward method for quantifying upper body adiposity without the limitations that other indices can have. Thus, this study aimed to analyze the relationship between NC, overall (body mass index [BMI]) and central obesity (waist circumference [WC]), and percentage of body fat (BF%) in men and women.

METHODS

The associations with NC quartiles (first quartile: reference group), BMI ≥30 kg/m², WC (>102 cm for men and >88 cm for women), and high BF% (≥21 for men and ≥29 for women) were compared and analyzed by logistic regression models adjusted for demographic characteristics, cardiovascular risk factors, and lean mass.

RESULTS

In 4283 adults (mean age: 44 y, 71.8% of men), the mean NC was higher in men (40.5 cm, range: 32-55 cm) than women (34.5 cm, range: 28.5-46 cm). Among men, the fourth quartile of NC (42.5-55 cm) was positively associated with obesity (multivariable odds ratio [OR]: 2.28, 95% confidence interval [CI]: 1.1-4.48). Among women, the fourth quartile of NC (36.5-46 cm) was associated with increased WC (multivariable OR: 2.98; 95% CI: 1.59-5.60). Progressive increases in the ORs were noticed across the associations between NC quartiles (second to fourth) and high BF% in men and women. The highest ORs were observed for the associations between high BF% and the fourth quartiles of NC in men (multivariable OR: 2.42; 95% CI: 1.49-3.93) and in women (multivariable OR: 29.19; 95% CI: 14.01-60.84).

CONCLUSIONS

The utility of NC as a measurement of obesity in clinical practice was demonstrated in this large sample of young to middle-aged adults. The highest NC values were positively associated with overall obesity in men and central obesity in women. Moreover, NC was closely associated with high BF% in both sexes, particularly in women.

Use of neck circumference as a predictor of cardiovascular risk in chronic kidney patients undergoing haemodialysis who are candidates for transplantation

INTRODUCTION

Patients undergoing haemodialysis are at great cardiovascular risk. Neck circumference (NC) is a simple and low-cost measure for estimating this risk precociously. The present study aimed to evaluate whether the cardiovascular risk obtained by NC is associated with the main cardiometabolic risk factors in patients on haemodialysis treatment who are on a waiting list for transplantation.

METHODS

A cross-sectional study was conducted including 96 patients in a single transplantation centre. Socio-demographic, clinical-laboratory and anthropometric data were collected. NC was considered as a dependent variable and the independent variables were body mass index (BMI), fasting glycaemia and lipid profile, triglyceride and high-density lipoprotein-cholesterol (TGL/HDL-C) ratio, and triglyceride and glycaemia (TyG) index. For the comparison of averages, we used Mann-Whitney and Student's t tests, as well as one-way analysis of variance and Kruskal-Wallis tests. Bivariate and multivariate logistic regression was performed for the association between NC and cardiometabolic risk factors. p < 0.05 was considered statistically significant.

RESULTS

There were higher BMI averages, blood glucose, triglycerides (TGL), TGL/HDL-C ratio and TyG index in the tertile 3 of the NC, whereas the HDL-C decreased as the tertile increased. There was a statistically significant risk of cardiovascular disease that was asscoiated, according to NC, with being overweight, high levels of TGL, TGL/HDL-C, TyG index and low HDL-C.

CONCLUSIONS

NC is shown to be associated with cardiometabolic risk factors in kidney patients undergoing haemodialysis who are on a transplant waiting list.

Comparison of anthropometric indices for predicting the risk of metabolic syndrome in older adults

Background. The prevalence of obesity and metabolic syndrome (MetS) is increasing, worldwide. Using a simple, efficient and reliable tool for predicting MetS is an essential approach in preventive health programs. The aim of this study was to compare the different anthropometric indices in predicting metabolic syndrome in older adults.Methods. This cross-sectional study is a part of the Amirkola Health and Ageing cohort Project (2011-2016). Of total, 1,488 older people aged 60-92 years were entered to the study. Medical and personal information of participants were collected by a questionnaire. After measuring the height, weight, waist circumference, hip circumference and neck circumference, body mass index, waist to hip ratio, waist to height ratio, abdominal volume index and conicity index were calculated. Independent t-test, chi-square and ROC curve were used to analyze the data.Results. Based on ATPIII-2005 diagnostic criteria, the prevalence of metabolic syndrome was 71.57%.The prevalence in female was higher than male. All of examined anthropometric indices, except neck circumference (p = 0.10), showed a significant difference in people with MetS compared to the individuals without metabolic syndrome (p<0.001). Waist to height ratio showed the largest area under the curve for predicting MetS (0.786; 95% CI: 0.76-0.81) followed by BMI (0.746; 95% CI: 0.71-0.77), AVI (0.745; 95% CI: 0.71-0.77), and waist circumference (0.743; 95% CI: 0.71-0.77).Conclusion. Waist to height ratio was the best predictor of MetS in older adults.

Neck Circumference and 10-Year Cardiovascular Risk at the Baseline of the ELSA-Brasil Study: Difference by Sex

Fundamento:

A circunferência do pescoço (CP) é uma medida indireta do tecido adiposo subcutâneo da parte superior do corpo, apontada como um preditor independente de doenças cardiometabólicas.

Objetivos:

Verificar a associação entre a CP e o risco cardiovascular em 10 anos (risco de doença cardiovascular [DCV] em 10 anos) em homens e mulheres separadamente.

Métodos:

Análise seccional com inclusão de 13.920 participantes da linha de base do Estudo Longitudinal da Saúde do Adulto (ELSA-Brasil). A associação entre a CP (utilizada como variável contínua e agregada em quartis) e o risco de DCV em 10 anos, estimado pelo Framingham Global Risk Score (FGRS), foi investigada por meio de modelos lineares generalizados após ajustes por características sociodemográficas, comportamentos em saúde, índice de massa corporal e circunferência da cintura. O nível de significância estatístico adotado foi de 5%.

Resultados:

A média da CP foi de 39,5 cm (desvio-padrão [DP] de ± 3,6) nos homens e 34,0 cm (DP de ±2,9) nas mulheres. Após ajustes, o aumento de 1 cm na CP foi associado ao incremento de 3% (IC 95%: 1,02 a 1,03) e 5% (IC 95%: 1,04 a 1,06) na média aritmética do risco de DCV em homens e mulheres, respectivamente. No último quartil da CP, homens e mulheres apresentaram um incremento de 18% (IC 95%: 1,13 a 1,24) e 35% (IC 95%: 1,28 a 1,43), respectivamente, na média aritmética do risco de DCV após ajustes.

Conclusões:

Verificamos associação positiva e independente entre a CP e o risco de DCV em 10 anos. Resultados sugerem que a CP pode contribuir para a predição de risco cardiovascular além daquele observado pelas medidas antropométricas clássicas.

Neck and waist circumference values according to sex, age, and body-mass index: Brazilian Longitudinal Study of Adult Health (ELSA-Brasil)

Body fat distribution predicts cardiovascular events better than body-mass index (BMI). Waist circumference (WC) and neck circumference (NC) are inexpensive anthropometric measurements. We aimed to present the conditional distribution of WC and NC values according to BMI, stratified by age and sex, from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) baseline data. We analyzed 15,085 ELSA-Brasil participants with complete data. We used spline quantile regression models, stratified by sex and age, to estimate the NC and WC quantiles according to BMI. To test a putative association between age and median NC or WC values, we built sex-specific median regression models using both BMI and age as explanatory variables. We present estimated 25th, 50th, 75th, and 90th percentiles for NC and WC values, according to BMI, age, and sex. Predicted interquartile intervals for NC values varied from 1.6 to 3.8 cm and, for WC values, from 5.1 to 10.3 cm. Median NC was not associated with age in men (P=0.11) nor in women (P=0.79). However, median WC increased with advancing age in both sexes (P<0.001 for both). There was significant dispersion in WC and NC values for a given BMI and age strata for both men and women. WC, but not NC values, were associated with increasing age. The smaller influence of advancing age on the relationship between BMI and NC (compared to WC) values may be useful in longitudinal studies.

Association of Neck Circumference with Anthropometric Indicators and Body Composition Measured by DXA in Young Spanish Adults

BACKGROUND

Due to a clinical and public health interest of neck circumference (NC), a better understanding of this simple anthropometric measurement, as a valid marker of body composition is necessary.

METHODS

A total of 119 young healthy adults participated in this study. NC was measured over the thyroid cartilage and perpendicular to the longitudinal axis of the neck. Body weight, height, waist circumference (WC), and hip circumference were measured. A Dual X-ray absorptiometry (DXA) scan was used to determine fat mass, lean mass, and visceral adipose tissue (VAT). Additionally, body mass index (BMI) and triponderal mass index (TMI), the waist to hip and waist to height ratios, and the fat mass and lean mass indexes (FMI and LMI, respectively) were calculated.

RESULTS

NC was positively associated in women (W) and men (M), with BMI (rW = 0.70 and rM = 0.84, respectively), TMI (rW = 0.63 and rM = 0.80, respectively), WC (rW = 0.75 and rM = 0.86, respectively), VAT (rW = 0.74 and rM = 0.82, respectively), Waist/hip (rW = 0.51 and rM = 0.67, respectively), Waist/height (rW = 0.68 and rM = 0.83, respectively) and FMI (rW = 0.61 and rM = 0.81, respectively). The association between NC and indicators of body composition was however weaker than that observed by BMI, TMI, WC and Waist/height in both women and men. It is of note that in women, NC was associated with FMI, VAT and LMI independently of BMI. In men, adding NC to anthropometric variables did not improve the prediction of body composition, while slight improvements were observed in women.

CONCLUSIONS

Taken together, the present study provides no indication for NC as a useful proxy of body composition parameters in young adults, yet future studies should explore its usefulness as a measure to use in combination with BMI, especially in women.

Association of moderate-to-vigorous physical activity with neck circumference in eight Latin American countries

BACKGROUND

Physical activity is a cornerstone in the prevention and treatment of obesity. There are relatively few studies that explore the effect of accelerometer-determined moderate-to-vigorous physical activity (MVPA) on neck circumference (NC), most of them confined to single high-income countries. The present study investigated the association of accelerometer-determined MVPA with NC in adolescents and adults from eight Latin American countries, which are mostly upper-middle income countries.

METHODS

The sample consisted of 2370 participants (47.8% male) from the Latin American Study of Nutrition and Health, a multicenter cross-sectional nutrition and health surveillance study of a nationally representative sample from eight Latin American countries (Argentina, Brazil, Chile, Colombia, Costa Rica, Ecuador, Peru, and Venezuela). Times (min/day) in MVPA (defined as time accumulated at ≥1952 activity counts/min) was assessed by ActiGraph GT3X+ accelerometer over 7 days. NC for adolescent was categorized as abnormal if circumference was > 34.5 cm for boys and > 31.25 for girls, whereas for adults the cut-off points for abnormal were > 39 cm for men and > 35 cm women. Multilevel logistic models, including country and region as random effects and adjusted for sex, age, socioeconomic level, and educational level, were used to study the association between MVPA and NC.

RESULTS

The average time of MVPA was 34.88 min/day, ranging from 31.16 in Venezuela to 40.27 in Chile. Concerning NC, 37.0% of the sample was classified as having elevated NC. Chile was the country with the highest percentage of people with elevated NC (56.9%), and Colombia had the lowest percentage (24.8%). Overall, the MVPA (min/day) was associated with elevated NC (OR = 0.994, CI95% = 0.990-0.998). In Costa Rica and Peru, there were significant associations between MVPA and NC when analyzed by country.

CONCLUSIONS

The present study provided evidence of significant associations between MVPA and NC in adolescents and adults from Latin America, independent of sex, age, socioeconomic level, and educational level. This analysis of accelerometry data and NC represents the first examination of these associations in eight Latin America countries. Further research is required to understand the differences between countries in the observed associations.

TRIAL REGISTRATION

ClinicalTrials.Gov NCT02226627 . Retrospectively registered on August 27, 2014.

Neck Circumference as an Anthropometric Indicator of Central Obesity in Patients with Prediabetes: A Cross-Sectional Study

Measurement of waist circumference has substantial variability and some limitations, while neck circumference is a simple and reliable anthropometric measure. This study aimed to assess the association between neck circumference and waist circumference and to identify the best cutoff of neck circumference that could predict central obesity in prediabetic patients. This cross-sectional study included adult patients with prediabetes, defined as having fasting plasma glucose levels ranging from 100 to 125 mg/dL or HbA1c ranging from 5.7 to 6.49%, who visited the outpatient clinic of Family Medicine Department, Ramathibodi Hospital, Thailand, during October 2014 and March 2016. Neck circumference was measured from the level just below the laryngeal prominence perpendicular to the long axis of the neck. Central obesity was defined as having waist circumference measurements greater than 90 and 80 cm for males and females, respectively. The correlation between neck circumference and waist circumference was explored by applying pairwise correlation coefficient. Receiver operating characteristic (ROC) curve analysis was performed and Youden index equal to "sensitivity - (1-specificity)" was calculated. Neck circumference that yielded the maximum Youden index was determined as the optimal cutoff point for prediction of central obesity. There were 1,534 patients eligible for this study. After adjusting for covariables, neck circumference was found to be significantly associated with waist circumference in both females and males, with β-coefficients of 1.01 (95% CI: 0.83, 1.20) and 0.65 (95% CI: 0.46, 0.85), respectively. After applying the ROC analysis, neck circumferences ≥ 32 cm in females and ≥ 38 cm in males were determined as the best cutoff values to predict central obesity. Neck circumference is strongly correlated with waist circumference in prediabetics and should be considered as an alternative to the waist circumference measurement in screening for central obesity.

Bone metabolism markers are associated with neck circumference in adult Arab women

The study aimed to determine whether neck circumference is associated with bone metabolism markers among adult Arab women and found modest but significant associations with bone resorption markers, suggesting that neck circumference, a surrogate measure of upper subcutaneous fat, influences bone turnover expression among adult females.

INTRODUCTION

Body fat distribution is associated with decreased bone resorption and neck circumference (NC), a surrogate measure for upper body fat, has never been tested as a marker that can reflect bone turnover. This is the first study aimed to analyze the associations between NC and several bone biomarkers among adult Saudi women.

METHODS

This cross-sectional study included a total of 265 middle-aged Saudi women [86 non-obese (mean age 52.7 ± 8.1; mean BMI 26.9 ± 2.3) and 179 obese (mean age 50.6 ± 7.5; mean BMI 35.7 ± 4.5)] recruited from primary care centers in Riyadh, Saudi Arabia. Anthropometrics included BMI, NC, waist and hip circumferences, total body fat percentage (%), and blood pressure. Biochemical parameters included glucose and lipid profile which were measured routinely. Serum levels of 25(OH) D, parathyroid hormone, RANKl, sclerostin, C-terminal telopeptide of collagen I (CTX-I), Dkk1, IL1β, osteoprotegerin, osteopontin, and osteocalcin were measured using commercially available assays.

RESULTS

In all groups, NC was inversely associated with PTH (R = - 0.22; p < 0.05) and positively associated with osteoprotegerin (R = 0.20; p < 0.05) even after adjustments for age and BMI. Using all anthropometric indices as independent variables showed that only NC explained the variance perceived in CTX-I (p = 0.049). In the non-obese, waist-hip ratio (WHR) was significantly associated with sclerostin (R = 0.40; p < 0.05) and body fat was significantly associated with osteopontin (R = 0.42; p < 0.05).

CONCLUSION

NC is modestly but significantly associated with bone biomarkers, particularly the bone resorption markers, among adult Arab women. The present findings highlight the importance of NC as measure of upper body subcutaneous fat in influencing bone biomarker expression in adult females.

Neck circumference in relation to glycemic parameters: a systematic review and meta-analysis of observational studies

BACKGROUND

Recent studies have suggested that neck circumference (NC) is a supplemental screening measure for diagnosing metabolic complications and might be associated with glycemic parameters. The aim of the present study was to to evaluate the association between NC and glycemic parameters.

METHODS

We systematically searched the electronic databases (including MEDLINE, Scopus, EMBASE, and Google scholar) up to April 2018. Observational studies that reported correlation coefficient between NC and glycemic parameters were included in the analysis. A random effects model was used to estimate overall Fisher's Z and 95% confidence interval of glycemic parameters including fasting plasma glucose (FBG), serum fasting insulin level, homeostasis model assessment-estimated insulin resistance (HOMA-IR) and glycated hemoglobin (HbA1c).

RESULTS

A total of 21 studies (44,031 participants) were eligible for including in the systematic review and meta-analysis. Significant correlations were found between NC and FBG (Fisher's Z = 0.18; 95% CI 0.16, 0.21), serum fasting insulin level (Fisher's Z = 0.34; 95% CI 0.26, 0.41), HOMA-IR (Fisher's Z = 0.36; 95% CI 0.29, 0.43) and HbA1c (Fisher's Z = 0.14; 95% CI 0.09, 0.20). Meta-regression analysis showed that NC were marginally associated with FBG in a linear manner (β = 0.008, P = 0.09); but not related to serum fasting insulin level, HOMA-IR, and HbA1c.

CONCLUSIONS

This meta-analysis of cross-sectional studies showed that NC was positively correlated with glycemic parameters including FBG, serum fasting insulin level, HOMA-IR, and HbA1c. Further investigations with prospective design are required to confirm these findings.

The association of neck circumference with risk of metabolic syndrome and its components in adults: A systematic review and meta-analysis

BACKGROUND & AIMS

Several prior studies suggested that neck circumference (NC) is a reliable diagnostic tool for risk of metabolic syndrome (MetS) and its features. However, not all studies support this view. Therefore, we aimed to perform a meta-analysis to summarize the association between NC with MetS and its components in adult populations.

METHODS AND RESULTS

PubMed/Medline, Web of Knowledge, and Scopus electronic databases were searched until May 31, 2017 to find relevant English-language papers. We included studies that examined the association of NC with risk of MetS, or at minimum, one of its components as outcomes. Of 2628 publications identified, 19 papers met selection criteria. We found no association between NC and MetS (odd ratio (OR): 0.73; 95% CI: 0.003, 1.47). However, there was a positive association between NC and waist circumference (WC) (r = 0.85; 95%: 0.75, 0.95; I²: 98.2%; p = 0.0001), BMI: (r:0.88; 95% CI: 0.74, 0.91, I²:97.3%), triglycerides (TG) (OR: 1.87; 95% CI: 1.60, 2.19; I²:58.4%; p = 0.03), TC (r:0.14; 95%CI: 0.05, 0.23, I²:94.1%), LDL-C (r: 0.18; 95%CI: 0.07, 0.29, I²:94.3%), hypertension (OR: 1.94; 95% CI:1.43, 2.64, I²:87.3%), systolic (r: 0.21, 95%CI: 0.19, 0.23; I²:67.1%) and diastolic blood pressures (r: 0.20, 95%CI: 0.16, 0.23; I²:79.7%), low HDL-C (r:-0.21; 95% CI: -0.26, -0.15, I² = 92.5%), as well as fasting blood sugar (FBS) concentrations (r: 0.20, 95%CI: 0.16, 0.24; I²:88.1%).

CONCLUSION

Subjects with higher NC were at approximately two-fold higher risk for hypertriglyceridemia compared to those with lower NC. We found positive associations between NC, WC, BMI, hypertension, FBS, TC, LDL-C, SBP, DBP, and low HDL-C concentrations. However, heterogeneity was considerably high. Therefore, the findings should be taken with caution. Future studies using longitudinal designs are needed to further understand the association between NC and features of MetS.

Cutoffs and cardiovascular risk factors associated with neck circumference among community-dwelling elderly adults: a cross-sectional study

CONTEXT AND OBJECTIVE:

In elderly people, measurement of several anthropometric parameters may present complications. Although neck circumference measurements seem to avoid these issues, the cutoffs and cardiovascular risk factors associated with this parameter among elderly people remain unknown. This study was developed to identify the cutoff values and cardiovascular risk factors associated with neck circumference measurements among elderly people.

DESIGN AND SETTING:

Cross-sectional study conducted in two community centers for elderly people.

METHODS:

435 elderly adults (371 women and 64 men) were recruited. These volunteers underwent morphological evaluations (body mass index and waist, hip, and neck circumferences) and hemodynamic evaluations (blood pressure values and heart rate). Receiver operating characteristic curve analyses were used to determine the predictive validity of cutoff values for neck circumference, for identifying overweight/obesity. Multivariate analysis was used to identify cardiovascular risk factors associated with large neck circumference.

RESULTS:

Cutoff values for neck circumference (men = 40.5 cm and women = 35.7 cm), for detection of obese older adults according to body mass index, were identified. After a second analysis, large neck circumference was shown to be associated with elevated body mass index in men; and elevated body mass index, blood pressure values, prevalence of type 2 diabetes and hypertension in women.

CONCLUSION:

The data indicate that neck circumference can be used as a screening tool to identify overweight/obesity in older people. Moreover, large neck circumference values may be associated with cardiovascular risk factors.