[Show abstract][Hide abstract] ABSTRACT: Background
Diabetes has been defined on the basis of different bio-markers, including fasting plasma glucose (FPG), 2-h plasma glucose in an oral glucose tolerance test (2hOGTT), and HbA1c. We assessed the effect of different diagnostic definitions on both the population prevalence of diabetes and the classification of previously undiagnosed individuals as having diabetes versus not having diabetes in a pooled analysis of data from population-based health examination surveys in different regions.
We used data from 96 population-based health examination surveys that had measured at least two of the bio-markers used for defining diabetes. Diabetes was defined using HbA1c (HbA1c ≥6·5% or history of diabetes diagnosis or using insulin or oral hypoglycemic drugs) compared with either FPG only or FPG-or-2hOGTT definitions (FPG ≥7·0 mmol/L or 2hOGTT ≥11·1 mmol/L or history of diabetes or using insulin or oral hypoglycemic drugs). We calculated diabetes prevalence, taking into account complex survey design and survey sample weights. We compared the prevalences of diabetes using different definitions graphically and by regression analyses. We calculated sensitivity and specificity of diabetes diagnosis based on HbA1c compared with diagnosis based on glucose among previously undiagnosed individuals (i.e., excluding those with history of diabetes or using insulin or oral hypoglycemic drugs). We calculated sensitivity and specificity in each survey, and then pooled results using a random-effects model. We assessed the sources of heterogeneity of sensitivity by meta-regressions for study characteristics selected a priori.
Population prevalence of diabetes based on FPG-or-2hOGTT was correlated with prevalence based on FPG alone (r=0·98), but was higher by 2–6 percentage points at different prevalence levels. Prevalence based on HbA1c was lower than prevalence based on FPG in 42·8% of age–sex–survey groups and higher in another 41·6%; in the other 15·6%, the two definitions provided similar prevalence estimates. The variation across studies in the relation between glucose-based and HbA1c-based prevalences was partly related to participants' age, followed by natural logarithm of per person gross domestic product, the year of survey, mean BMI, and whether the survey population was national, sub-national, or from specific communities. Diabetes defined as HbA1c 6·5% or more had a pooled sensitivity of 52·8% (95% CI 51·3–54·3%) and a pooled specificity of 99·74% (99·71–99·78%) compared with FPG 7·0 mmol/L or more for diagnosing previously undiagnosed participants; sensitivity compared with diabetes defined based on FPG-or-2hOGTT was 30·5% (28·7–32·3%). None of the preselected study-level characteristics explained the heterogeneity in the sensitivity of HbA1c versus FPG.
Different biomarkers and definitions for diabetes can provide different estimates of population prevalence of diabetes, and differentially identify people without previous diagnosis as having diabetes. Using an HbA1c-based definition alone in health surveys will not identify a substantial proportion of previously undiagnosed people who would be considered as having diabetes using a glucose-based test.
[Show abstract][Hide abstract] ABSTRACT: The aim of this study was to assess sustained hypertension in children and its impact on cardiovascular target organ damage (TOD). Blood pressure (BP) was measured in children in Beijing in 2009. Primary hypertension was diagnosed based on three separate visits. Hypertensive children and normotensive children were followed up in 2011. According to these evaluations, three groups were defined: sustained hypertension, non-sustained hypertension and normotensive. Cardiovascular TOD and metabolic disorders were evaluated using pulse-wave velocity (PWV), carotid intima-media thickness (cIMT), and assessments of left ventricular structure and kidney function. A total of 3032 children aged 9-15 years participated in this survey, of whom 128 were diagnosed with hypertension after three separate BP measurements. Eighty out of 128 (62.5%) hypertensive and 158 normotensive children were available for follow-up in 2011. Forty-eight children were defined as having sustained hypertension, 38 as non-sustained hypertension and 152 as normotensive. Mean levels of brachial-ankle PWV (baPWV), left ventricular mass, left ventricular mass index (LVMI) and cIMT were significantly different between the three groups (p < 0.01). Compared to normotensives, the odds ratios and 95% confidence intervals for elevated LVM and cIMT were 5.27 (1.57-17.66) and 2.88 (1.03-8.09) in the non-sustained hypertensive group, and 3.28 (1.00-10.74) and 7.25 (2.69-19.58) in the sustained hypertensive group. The children with sustained hypertension have the highest risk of developing arterial stiffness, left ventricular hypertrophy and early blood vessel endothelium damage. The indices of cIMT, LVMI and PWV were useful to identify children at high risk of cardiovascular TOD.
[Show abstract][Hide abstract] ABSTRACT: To quantify the prevalence of dyslipidemia among children and adolescents in China.
Chinese Biomedical Database (CBM), Wanfang Databases, China National Knowledge Infrastructrue (CNKI) and PubMed were comprehensively searched. Original reports were selected if data on prevalence estimates of dyslipdemia among children and adolescents in China, was provided under cross-sectional epidemiological studies. Quality of the literature was evaluated through the STROBE statement. The prevalence through Meta was estimated using the Strata 11.0 software. Subgroup analysis was undertaken on gender, age, regions and secular trends issues. Sensitivity analysis was performed to evaluate the impact of quality or standard of diagnosis.
A total of 24 papers were included in this Meta-analysis, with the whole sample size as 129 426. The overall pooled-prevalence of total dsylipidemia was estimated at 25.3% (95% CI: 12.7%-37.8%). Prevalence rates of high TC, LDL-C, TG, low HDL-C and hyperlipemia were 4.1% (95% CI:3.4%-4.9%), 5.3% (95% CI:3.9%-6.7%), 8.5% (95% CI:6.3%-10.7%), 6.8% (95% CI: 3.7%-9.9%), 4.8% (95%CI:0.6%-9.1%), respectively. Girls (3.4%) had lower prevalence of high TG than boys (5.6%), but having higher prevalence of other different types dyslipidemia. Children aged 7-18 years had higher overall prevalence of dyslipidemia (31.6%) when compared to children aged 2-6 years (9.0%). There were no statistically significant differences for subgroups of age, region and period regarding the prevalence rates of high TG, TC and low HDL-C(P > 0.05).
Prevalence of dyslipidemia was high and with increasing trend among children and adolescents in China. Early screening and prevention programs on abnormal serum lipids should be emphasized and promoted.
Zhonghua liu xing bing xue za zhi = Zhonghua liuxingbingxue zazhi 04/2015; 36(1):71-7.
[Show abstract][Hide abstract] ABSTRACT: To assess the cardiovascular structure and function in children with confirmed primary hypertension, and to explore the impact of hypertension and related risk factors on cardiovascular structure and function of children.
Parameters related to cardiac structure, vascular structure and function were measured in 213 hypertensive children, who were confirmed upon repeated measurements on separate occasions. A total of 197 healthy children were recruited as controls.
1) In hypertensive children, left ventricular end-diastolic diameter (LVEDd), left ventricular end-systolic diameter (LVESd), left ventricular mass (LVM), left ventricular mass index (LVMI), left ventricular posterior wall thickness (LVPT) and interventricular septal thickness (IVST) were all significantly higher than their counterparts (P < 0.05). No statistical differences were found in carotid intima-media thickness (cIMT), relative wall thickness (RWT) and brachial ankle pulse wave velocity (ba-PWV). 2) Compared with controls, LVEDd, LVESd, LVM, LVMI were all significantly higher in hypertensive children (P < 0.05), regardless of age group or weight-status. No statistical differences were found in ccIMT and RWT, while ba-PWV was statistically higher in controls among children aged 6-12 years. 3) Data from multiple linear regression analysis noticed that LVMI was associated with age, sex, BMI and hypertension while RWT was associated with age and BMI.
In children with primary hypertension, changes of vascular structure and function were not shown but left ventricular remodeling and early changes of function had been developed in children under 12 years old.
Zhonghua liu xing bing xue za zhi = Zhonghua liuxingbingxue zazhi 04/2015; 36(4):332-6.
[Show abstract][Hide abstract] ABSTRACT: Objective An obesity-related gene, Fas apoptotic inhibitory molecule 2 (FAIM2), is regulated by nutritional state and the methylation levels of the FAIM2 promoter are significantly associated with obesity. Lifestyle factors, such as sedentary behaviour and physical activity, might modify epigenetic patterns that have been related to obesity. Whether the molecular mechanisms by which FAIM2 affects obesity are involved in lifestyle is unclear. This study investigates the potential differences of the FAIM2 promoter methylation with sedentary behaviour and physical activity in obese and lean children.
Design Cohort study.
Setting Institute of Pediatrics in China.
Participants 59 obese cases and 39 lean controls aged 8–18 years recruited from a cross-sectional survey of children from Beijing in 2013.
Primary and secondary outcome measures The FAIM2 promoter methylation was quantified using the Sequenom MassARRAY platform. Sedentary behaviour and physical activity were investigated using a questionnaire. The influences of different lifestyles on methylation variations in obese and lean children were examined by multiple linear regression.
Results The methylation levels at seven CpG sites of the FAIM2 promoter were significantly associated with sedentary behaviour, especially the methylation levels at site −975, site −413, sites −362 and −360, and sites −353 and −349 (p=0.00004, 0.00009, 0.0006 and 0.00005, respectively). There were significant differences between the methylation levels at four CpG sites in obese and lean participants with high or moderate physical activity level <150 min/week.
Conclusions This study provides the first evidence that there are significant differences in the associations of the FAIM2 promoter methylation with sedentary behaviour and physical activity between obese and lean children. Our results suggest that lifestyle may possibly be mediating the process of the FAIM2 involved in obesity.
BMJ Open 04/2015; 5(4):e007670. DOI:10.1136/bmjopen-2015-007670 · 2.27 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: We seek to observe the association between childhood obesity by different measures and adult obesity, metabolic syndrome (MetS), and diabetes. Thousand two hundred and nine subjects from "Beijing Blood Pressure Cohort Study" were followed 22.9 ± 0.5 years in average from childhood to adulthood. We defined childhood obesity using body mass index (BMI) or left subscapular skinfold (LSSF), and adult obesity as BMI ≥28 kg/m(2). MetS was defined according to the joint statement of International Diabetes Federation and American Heart Association with modified waist circumference (≥90/85 cm for men/women). Diabetes was defined as fasting plasma glucose ≥7.0 mmol/L or blood glucose 2 h after oral glucose tolerance test ≥11.1 mmol/L or currently using blood glucose-lowering agents. Multiple linear and logistic regression models were used to assess the association. The incidence of adult obesity was 13.4, 60.0, 48.3, and 65.1 % for children without obesity, having obesity by BMI only, by LSSF only, and by both, respectively. Compared to children without obesity, children obese by LSSF only or by both had higher risk of diabetes. After controlling for adult obesity, childhood obesity predicted independently long-term risks of diabetes (odds ratio 2.8, 95 % confidence interval 1.2-6.3) or abdominal obesity (2.7, 1.6-4.7) other than MetS as a whole (1.2, 0.6-2.4). Childhood obesity predicts long-term risk of adult diabetes, and the effect is independent of adult obesity. LSSF is better than BMI in predicting adult diabetes.
[Show abstract][Hide abstract] ABSTRACT: Metabolically healthy obesity (MHO) begins in childhood and continues into adulthood. However, the association between MHO and the risk of developing hypertension remains controversial. A prospective cohort study was conducted to investigate the risk of hypertension in MHO and metabolically unhealthy normal-weight (MUNW) Chinese children and adolescents. A total of 1183 participants, 6-18 years old at baseline with normal blood pressure values, were studied using follow-up data from the cohort of the Beijing Child and Adolescent Metabolic Syndrome (BCAMS) study. The participants were classified according to the body mass index and the presence/absence of metabolic abnormality, which was defined by metabolic syndrome (MetS) or insulin resistance (IR). During the 6-year follow-up period, 239 (20.2%) participants developed incident hypertension. After adjusting for age, sex, physical activity, pubertal stage, dietary habits and family history of hypertension, an increased risk for hypertension was observed in the MHO individuals (risk ratio, RRMetS 5.42; 95% confidence interval (CI) 3.19-9.22 and RRIR 7.59; 95% CI 1.64-35.20) compared with their metabolically healthy normal-weight counterparts. Independent of the definition of metabolic abnormality, the MUNW subjects did not have an elevated incidence of hypertension. These results suggest that the risk of developing hypertension is increased in the MHO but not in the MUNW individuals.Journal of Human Hypertension advance online publication, 5 February 2015; doi:10.1038/jhh.2014.124.
Journal of Human Hypertension 02/2015; 29(9). DOI:10.1038/jhh.2014.124 · 2.70 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To examine the impact of single nucleotide polymorphisms in obesity-related genes on risk of obesity and metabolic disorder in childhood.
A total of 3 503 Chinese children aged 6 to 18 years participated in the study, including 1 229 obese, 655 overweight and 1 619 normal weight children (diagnosed by the Chinese age- and sex- specific BMI cutoffs). Body size parameters were assessed and venipuncture blood samples were collected after a 12-hour overnight fast. Plasma glucose, insulin and serum lipid profiles were measured.Genomic DNA was isolated from peripheral blood white cells using the salt fractionation method. A total of 11 single nucleotide polymorphisms were genotyped by TaqMan allelic discrimination assays with the GeneAmp 7900 sequence detection system (Applied Biosystems, Foster City, CA, USA) (FTO rs9939609, MC4R rs17782313, GNPDA2 rs10938397, FAIM2 rs7138803, BDNF rs6265, NPC1 rs1805081, PCSK1 rs6235, KCTD15 rs29941, BAT2 rs2844479, SEC16B rs10913469 and SH2B1 rs4788102). Multiple factor analysis was performed to estimate the association between the variant and obesity-related traits. The false discovery rate (FDR) approach was used to correct for multiple comparisons.
After sex, age and pubertal stage adjustment and correction for multiple testing, the rs9939609-A, rs17782313-C, rs10938397-G, and rs7138803-A alleles were associated with higher BMI (β = 0.352-0.747), fat mass percentage(β = 0.568-1.113), waist circumference (β = 0.885-1.649) and waist-to-height ratio(β = 0.005-0.010) (all P values < 0.01) in Chinese children. The rs6265-G allele increased BMI(β = 0.251, P = 0.020). The rs9939609-A, rs17782313-C, and rs10938397-G and rs6265-G alleles were also associated with risk of obesity (OR = 1.386, 95%CI:1.171-1.642; OR = 1.367, 95%CI:1.196-1.563; OR = 1.242, 95%CI:1.102-1.400; OR = 1.156, 95%CI:1.031-1.296).Rs7138803 was associated with risk of obesity only in boys (OR = 1.234, 95%CI:1.043-1.460). GNPDA2 rs10938397-G allele was associated with risk of insulin resistance(OR = 1.205, 95%CI:1.069-1.359), but there was no significance after adjusting for BMI.
The association of FTO rs9939609-A, MC4R rs17782313-C, GNPDA2 rs10938397-G, and FAIM2 rs7138803-A with higher BMI, fat mass percentage, waist circumference, and waist-to height ratio and risk of obesity, and BDNF rs6265-G allele may increase BMI and obesity risk in Chinese children. GNPDA2 rs10938397-G may increase the risk of childhood insulin resistance depending on BMI.
Zhonghua yu fang yi xue za zhi [Chinese journal of preventive medicine] 09/2014; 48(9):776-83.
[Show abstract][Hide abstract] ABSTRACT: Objectives:
Previous studies showed that prevalence of abdominal obesity among US children and adolescents increased significantly between 1988-1994 and 2003-2004. However, little is known about recent time trends in abdominal obesity since 2003-2004.This study was to provide recent updated national estimates of childhood abdominal obesity and examine the trends in childhood abdominal obesity from 2003 to 2012.
Data were from the National Health and Nutrition Examination Survey (NHANES) conducted during 5 time periods (2003-2004, 2005-2006, 2007-2008, 2009-2010, and 2011-2012). A total of 16,601 US children and adolescents aged 2 to 18 years were included. Abdominal obesity is defined as a waist circumference (WC) ≥ gender- and age-specific 90th percentile based on data from NHANES III (1988-1994) and a waist-to-height (WHtR) ≥0.5, respectively.
In 2011-2012, 17.95% of children and adolescents aged 2 to 18 years were abdominally obese defined by WC, and 32.93% of those aged 6 to 18 years were abdominally obese defined by WHtR. Mean WC and WHtR and prevalence of abdominal obesity kept stable between 2003-2004 and 2011-2012, independently of gender, age, and race/ethnicity. However, there was a significant decrease in abdominal obesity among children aged 2 to 5 years.
The prevalence of abdominal obesity leveled off among US children and adolescents from 2003-2004 to 2011-2012.
[Show abstract][Hide abstract] ABSTRACT: Objective:
To explore the relationship between high-sensitivity C-reactive protein (hsCRP) and obesity/metabolic syndrome (MetS) related factors in children.
403 children aged 10-14 and born in Beijing were involved in this study. Height, weight, waist circumference, fat mass percentage (Fat%), blood pressure (BP), hsCRP, triglyceride (TG), total cholesterol (TC), fasting plasma glucose (FPG), high and low density lipoprotein cholesterol (HDL-C, LDL-C) were observed among these children. hsCRP was transformed with base 10 logarithm (lgCRP). MetS was defined according to the International Diabetes Federation 2007 definition. Associations between MetS related components and hsCRP were tested using partial correlation analysis, analysis of covariance and linear regression models.
1) lgCRP was positively correlated with BMI, waist circumference, Fat%,BP, FPG, LDL-C and TC while negatively correlated with HDL-C. With BMI under control, the relationships disappeared, but LDL-C (r = 0.102). 2) The distributions of lgCRP showed obvious differences in all the metabolic indices, in most groups, respectively. With BMI under control, close relationships between lgCRP and high blood pressure/high TG disappeared and the relationship with MetS weakened. 3) Through linear regression models, factors as waist circumference, BMI, Fat% were the strongest factors related to hsCRP, followed by systolic BP, HDL-C, diastolic BP, TG and LDL-C. With BMI under control, the relationships disappeared, but LDL-C(β = 0.045).
hsCRP was correlated with child obesity, lipid metabolism and MetS. Waist circumference was the strongest factors related with hsCRP. Obesity was the strongest and the independent influencing factor of hsCRP.
Zhonghua liu xing bing xue za zhi = Zhonghua liuxingbingxue zazhi 06/2014; 35(6):621-625.
[Show abstract][Hide abstract] ABSTRACT: The associations between common variants in the fat mass- and obesity-associated (FTO) gene and obesity-related traits may be age-dependent and may differ by sex. The present study aimed to assess the association of FTO rs9939609 with body mass index (BMI) and the risk of obesity from childhood to adolescence, and to determine the age at which the association becomes evident.
Totally 757 obese and 2,746 non-obese Chinese children aged 6-18 years were genotyped for FTO rs9939609. Of these, a young sub-cohort (n = 777) aged 6-11 years was reexamined 6 years later. Obesity was defined using the sex- and age-specific BMI cut-offs recommended by the International Obesity Task Force.
The associations of FTO rs9939609 with BMI and obesity did not appear until children reached 12-14 years. The variant was associated with an increased BMI in boys (β = 1.50, P = 0.004) and girls (β = 0.97, P = 0.018), respectively. Thereafter, the magnitude of association increased in girls at ages 15-18 years (β = 2.02, P<0.001), but not boys (β = 0.10, P>0.05). Age was found to interact with the variant on BMI (P<0.001) and obesity (P = 0.042) only in girls. In the sub-cohort, the associations of FTO rs9939609 with BMI (β = 1.07, P = 0.008) and obesity (OR = 2.09, 95% CI: 1.12, 3.91) were only observed 6 years later (ages 12-18 years) in girls, even after adjusting for baseline BMI.
The association between FTO rs9939609 and obesity-related traits may change from childhood to adolescence in Chinese individuals, and the association may start as early as age 12 years, especially in girls.
PLoS ONE 05/2014; 9(5):e97545. DOI:10.1371/journal.pone.0097545 · 3.23 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Objective:
To study the dietary habits of school-age children in urban and rural districts and their association with blood pressure levels in Beijing, China.
A stratified, randomly clustered sampling design was used, 29 primary and secondary schools from four urban districts and three rural districts in Beijing were randomly selected in 2004. 20 638 children aged 6-18 years old were surveyed, and 19 072 of them provided completed usable data. The weight, height and blood pressure of the subjects were measured according to standard method.10 food-groups' information was collected by a semi-quantitative food frequency questionnaire. The relationship between different dietary habits and the blood pressure levels in school children was analyzed by multiple linear regression model.
The prevalence of obesity among children in urban area (12.2%, 1 218/9 984) was higher than that in rural area (6.7%, 609/9 088) (χ(2) = 4.62, P < 0.05) , whereas the prevalence of hypertension among children in urban area (8.0%, 799/9 984) was lower than that in rural area (8.9%, 809/9 088) (χ(2) = 167.32, P < 0.05) . The diastolic blood pressure (DBP) among children was (65.7 ± 8.6) mmHg (1 mmHg = 0.133 kPa) in urban area and (67.0 ± 8.7) mmHg in rural area, respectively (F = 86.44, P < 0.05) , and the systolic blood pressure (SBP) among children was (103.4 ± 12.2) mmHg in urban area and (104.3 ± 11.6) mmHg in rural area, respectively (F = 11.33, P < 0.05) . Factor analysis revealed 4 dietary habits labeled prudent habit, protein habit, high-fat and high-calorie habit and vegetables and fruits habit. The 4 dietary habits' variance contribution rate respectively was 24.7%, 14.6%, 14.0%, 8.9%, and the 4 dietary habits totally reflect 62.2% characteristics of the 10 food-groups.In urban area, prudent habit was inversely associated with DBP (β' = -0.026, P < 0.05) , Protein habit was inversely associated with both children's SBP (β' = -0.018, P < 0.05) and DBP (β' = -0.030, P < 0.05) .In rural area, prudent habit was associated with children's SBP (β' = -0.050, P < 0.05) and DBP (β' = -0.039, P < 0.05) .
The dietary habits of school age children varied by sociodemographic characters in Beijing. The prudent habit and protein habit may decrease the children's blood pressure levels.
Zhonghua yu fang yi xue za zhi [Chinese journal of preventive medicine] 05/2014; 48(5):340-4.