Dong-Hui Lou

Neck circumference is an accurate and simple index for evaluating overweight and obesity in Han children

Background: The prevalence of obesity has reached alarming levels in recent years. Neck circumference (NC) has been shown to be an indicator of central adiposity. Aim: The purpose of this study was to analyse whether NC can be used to determine overweight and obesity in Han Chinese children. Subjects and methods: In 2011, anthropometric measurements were gathered in a cross-sectional, population-based study of 2847 Han children aged 7–12 years. Overweight and obesity were defined according to the 2004 Chinese obesity task force definition. Receiver operating characteristic curve analyses were conducted to assess the accuracy of NC as a diagnostic test for elevated body mass index (BMI) (overweight and obesity). Results: The prevalence of overweight and obesity in boys was 18.0% and 26.0%, respectively, and 11.7% and 15.7%, respectively, for girls. The mean NC in boys was significantly greater than in girls (29.2 ± 3.1 cm vs 28.1 ± 2.8 cm, p < 0.001). NC was significantly correlated with age, BMI and waist circumference in both boys and girls (p < 0.001 for all comparisons). NC cut-off values for elevated BMI were between 27.4∼31.3 cm in boys and 26.3∼31.4 cm in girls. The sensitivities were 75.5∼86.7% in boys and 80.0∼92.5% in girls. The specificities were 73.9∼91.7% in boys and 74.7∼93.3% in girls. Conclusion: The present study demonstrates that NC is a simple, inexpensive and accurate measurement that may be used to identify overweight and obesity in Han children.

Glycemic Variability in Abdominally Obese Men With Normal Glucose Tolerance as Assessed by Continuous Glucose Monitoring System

The purpose of this study was to observe both the glycemic variability in abdominally obese men with normal glucose tolerance (NGT) and the relationship between glycemic variability and early atherosclerosis. This case‐control study included 23 abdominally obese men (waist circumference (WC) ≥90 cm) and 23 nonabdominally obese men (WC <90 cm) with NGT who were between 20 and 50 years of age. All subjects were of the Han ethnicity. The cases and controls were age‐matched. A continuous glucose monitoring system (CGMS) was used in this study. With the CGMS, the standard deviation of blood glucose (SDBG) and the mean amplitude of glucose excursion (MAGE) were calculated to estimate glycemic variability. The carotid intima‐media thickness (CIMT) was used as a surrogate marker of early atherosclerosis. Mean blood glucose (MBG) (6.13 ± 0.94 vs. 5.55 ± 0.87 mmol/l), SDBG (0.89 ± 0.34 vs. 0.64 ± 0.24 mmol/l), MAGE (2.05 ± 0.83 vs. 1.57 ± 0.52 mmol/l), and CIMT (0.73 ± 0.12 vs. 0.67 ± 0.05 mm) were significantly higher in the abdominally obese men than in the nonabdominally obese men (P < 0.05). WC positively correlated with MBG (r = 0.302, P = 0.041), SDBG (r = 0.362, P = 0.013), MAGE (r = 0.302, P = 0.041), and CIMT (r = 0.487, P = 0.001). CIMT did not correlate with MBG (r = 0.206, P = 0.169), SDBG (r = 0.114, P = 0.450), and MAGE (r = 0.085, P = 0.574). After multivariate analysis, WC was still significantly associated with MBG (β = 0.025, P = 0.041), SDBG (β = 0.010, P = 0.013), MAGE (β = 0.019, P = 0.042), and CIMT (β = 0.008, P = 0.022). This study demonstrates that glycemic variability is increased in abdominally obese men with NGT. A relationship between glycemic variability and atherosclerosis was not observed in this study and requires further investigation.

A new modified blood pressure-to-height ratio simplifies the screening of hypertension in Han Chinese children.

The present study evaluated the simplicity and accuracy of a new modified blood pressure-to-height ratio (MBPHR3) in identifying hypertension among Han children aged 7–12 years. In 2011, anthropometric measurements were collected as part of a cross-sectional population-based study of 1352 Han children aged 7–12 years. Receiver operating characteristic curve analyses were performed to assess the accuracy of the modified systolic blood pressure-to-height ratio (MSBPHR3) and the modified diastolic blood pressure-to-height ratio (MDBPHR3) as diagnostic tests for the detection of elevated SBP and DBP, respectively. The accuracies of MSBPHR3 and MDBPHR3 (as assessed by the area under the curve) in identifying elevated SBP and DBP were greater than 0.85 (0.974–0.995). When the MBPHR3 was used to identify hypertensive children, the sensitivity was 100% in boys and 100% in girls. The specificity was 93.8% in boys and 97.1% in girls. In conclusion, the MBPHR3 is a simple, accurate and non-age-dependent index for the screening of hypertension in Han children.

Prevalence of impaired fasting glucose and analysis of risk factors in Han adolescents

OBJECTIVE To evaluate the prevalence of impaired fasting glucose (IFG) and its relationship with cardiovascular risk factors in Han adolescents aged 13 to 18 years. METHODS Step 1: A cross-sectional study was conducted on 3937 Han adolescents. IFG was defined as a fasting glucose of 5.6 to 7.0 mmol/l. Measurements included anthropometric measurements, fasting plasma glucose (FPG), and serum lipids. Step 2: We identified 60 adolescents with IFG from the IFG group using a random number table, and 60 adolescents with normal fasting glucose (NFG) were matched for age and gender with the random IFG sample. Serum true insulin (TI) was further measured. RESULTS (1) The prevalence of IFG was 3.5% and was similar in boys and girls (3.9% vs. 3.1%, P=.177). The prevalence of IFG in adolescents with a family history of type 2 diabetes (FHD) was higher than in adolescents without FHD (6.3% vs. 2.5%, P=.000). (2) In logistic regression, the clustering of cardiovascular risk factors among adolescents with IFG was 1.889 (95% CI: 1.125-3.171, P=.016) times compared with adolescents with NFG adjusted by age and gender. (3) Multiple linear regression analysis using FPG as the dependent variable showed that waist circumference (beta=0.003, P=.000) was a significant independent predictor. (4) In Step 2, the IFG group showed significantly higher levels of lnTI and lnHOMA-IR than the NFG group (P<.01). FPG was a significant independent predictor for lnTI (beta=0.478, P=.000) and lnHOMA-IR (beta=0.671, P=.000). CONCLUSION We found a high prevalence of IFG in Han adolescents. Genetic susceptibility and abdominal obesity were the main factors causing adolescent IFG. Adolescents with IFG increased the clustering of cardiovascular risk factors.

Value of dual-energy X-ray absorptiometry derived parameters vs anthropometric obesity indices in the assessment of early atherosclerosis in abdominally obese men

SUMMARY OBJECTIVE The purpose of this study was to evaluate the value of dual-energy X-ray absorptiometry (DEXA) derived parameters vs anthropometric obesity indices in the assessment of early atherosclerosis in abdominally obese men. METHODS This case-control study included 44 abdominally obese men (waist circumference ≥ 90 cm) and 30 non-abdominally obese men (waist circumference < 90 cm) who were between 20 and 50 years of age. All subjects were of the Han ethnicity. The carotid intima-media thickness (CIMT) was used as a surrogate marker of early atherosclerosis. In the first multiple linear regression model, body fat distribution was assessed by anthropometric obesity indices, while in the second one it was quantified by DEXA-derived parameters. RESULTS CIMT (0.74 ± 0.11 vs 0.67 ± 0.04 mm) were significantly higher in the abdominally obese men than in the non-abdominally obese men (P < 0.01). CIMT was positively correlated with anthropometric obesity indices (r: 0.352-0.488, P < 0.01) and the indices from DEXA(r: 0.244-0.482, P < 0.05). The correlation coefficients of anthropometric obesity indices and the indices from DEXA were highest for waist to height ratio and trunk fat mass, respectively. In model 1, 23.8% of the total variance of CIMT was due to waist to height ratio. In model 2, trunk fat mass explained 23.2% of the total variance of CIMT. CONCLUSIONS The present study demonstrates the importance of characterizing body fat distribution in identifying early atherosclerosis. Body fat distribution evaluated by dualenergy X-ray absorptiometry was associated with CIMT, but was not superior to anthropometric measurements.

The relationship between the waist-to-height ratio and glucose and lipid metabolism in Han adolescents

ObjectiveTo evaluate the relationship between waist-to-height ratio (WHtR) and glucose and lipid metabolism in Han adolescents aged 13–15 years.MethodsA study was conducted on 1665 Han adolescents aged 13–15 years. Measurements included height, weight, waist circumference, fasting plasma glucose(FPG), triglyceride and high-density lipoprotein cholesterol. The subjects were divided into two groups according to WHtR.ResultsCompared with the control group (n=1340,WHtR<0.46), the abdominal obesity group(n=325,WHtRe”0.46) had significantly higher levels of body mass index (BMI) (26.3±3.6 vs 18.9±2.3), WHtR (0.51±0.04 vs 0.40±0.03), FPG (4.99±0.48 vs 4.86±0.46), and triglyceride (1.21±0.62 vs 0.87±0.41), and a lower level of high-density lipoprotein cholesterol (1.26±0.27 vs 1.46±0.30) (P<0.01). Logistic regression analysis showed that after controlling for age, sex and BMI, the elevated FPG and dyslipidemia risk odds ratios of the abdominal obesity group were 1.954 (95% CI:1.250∼3.054) and 2.012 (95% CI:1.204∼3.362) (P<0.01) respectively. When clustered, the odds ratio of elevated FPG and dyslipidemia was 6.659 (95% CI: 1.337∼33.159) (P<0.01).ConclusionThe waist-to-height ratio is an appropriate measure to assess dyslipidemic-diabetic adolescents and should be used to guide early intervention with the aim of future prevention of these linked diseases.