Prevalence of nonalcoholic fatty liver disease and metabolic abnormalities in 387 obese children and adolescents in Beijing, China / 中华流行病学杂志

<p><b>OBJECTIVE</b>To determine the prevalence of nonalcoholic fatty liver disease (NAFLD) and metabolic abnormalities in obese children and adolescents in Beijing.</p><p><b>METHODS</b>This study involved 387 obese children and adolescents, aged 12 to 17 years in Beijing. Data on anthropometric measurements was collected, including weight, height and age. All subjects underwent a clinic examination containing fasting blood and liver ultrasonography. Nonalcoholic fatty liver disease was diagnosed using diagnostic criteria for nonalcoholic fatty liver disease which was recommended by the Fatty liver and Alcoholic Liver Disease Study Group of Liver Disease Association in China.</p><p><b>RESULTS</b>174 out of the 387 children were diagnosed as having NAFLD. The overall prevalence of NAFLD was 45.0% in this study population. The prevalence rates of NAFLD did not show significant difference between girls and boys. The prevalence rates of diabetes mellitus and IFG were 0.8% and 49.1% respectively. The prevalence rates of HTG, HTC, HLDL-C, LHDL-C, IFG, elevated ALT (or AST) and acanthosis nigricans were 6.3%, 4.0%, 37.9%, 22.8%, 46.0%, 17.8% and 28.5% in students combined with obesity and NAFLD, respectively. In the NAFLD subgroup, higher prevalence of high TG, acanthosis nigricans, abnormal ALT or AST were seen. With the increasing of obesity, the level of LDL-C, TG, liver function disturbance and prevalence of NAFLD and acanthosis nigricans were aggravated. Under binary logistic regression analysis, results showed that high BMI, acanthosis nigricans and TG were significantly correlated with NAFLD in obese children and adolescent population.</p><p><b>CONCLUSION</b>NAFLD was common in obese children, and the prevalence of NAFLD in obese children was 45.0%. Higher BMI, acanthosis nigricans and abnormal TG were independent risk factors for NAFLD in obese children. Obese children who had been exposed to high risk factors should take the ultrasonography.</p>

Association between obesity in childhood and hypertension incidence: a prospective cohort study / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore the impact of obesity level and the level change in childhood on hypertension incidence.</p><p><b>METHODS</b>A perspective cohort study was conducted. As part of Beijing Child and Adolescent Metabolic Syndrome Study, 2189 aged 6 - 16 year non-hypertensive children was followed up in December, 2010. In this study, height, weight, waist circumference (WC) and blood pressure was measured at follow-up, and body mass index (BMI) and WC was respectively used to assess overweight, obesity and abdominal obesity. Non-conditional logistic regression was used to evaluate the association between baseline obesity status, change of obesity status and hypertension incidence. OR and 95%CI were computed in the model using obese status as dummy variable and hypertension at follow up visit as dependent variable.</p><p><b>RESULTS</b>The total hypertension incidence of 1184 subjects during 6 years follow-up was 19.9% (236/1184). The hypertension incidence in male (23.2%, 149/643) was higher than that in female (16.1%, 87/541) (χ(2) = 9.257, P = 0.002). The hypertension incidence of non-overweight, overweight and obese children at baseline was 8.7% (45/519), 19.3% (35/181) and 32.4% (156/484) respectively (χ(2) = 9.332, P < 0.001), and the incidence of non-obese and abdominal obese children at baseline was respectively 10.3% (63/613) and 30.7% (173/567) (χ(2) = 77.753, P < 0.001). Hypertension incidence in the baseline obesity group was higher than the non-overweight (BMI: OR = 4.9, 95%CI: 3.4 - 7.0) and non-obese group (WC: OR = 3.9, 95%CI: 2.8 - 5.3). The hypertension incidence increased with the follow-up BMI/WC level, based on the same baseline level of BMI and WC. The hypertension risk increased to 0.21 and 0.07 times respectively with elevation of baseline BMI level by 1 kg/m(2) and WC level by 1 cm, and OR (95%CI) were 1.21 (1.16 - 1.26) and 1.07 (1.05 - 1.09), respectively. Similarly, the hypertension risk increased 0.16 and 0.05 times respectively with the elevation of BMI level change by 1 kg/m(2) and 1 cm, and OR (95%CI) were 1.16 (1.11 - 1.22) and 1.05 (1.03 - 1.07), respectively.</p><p><b>CONCLUSION</b>Obesity and increased obesity level change in childhood can increase the risk of incident hypertension.</p>

Prevalence and associated factors of school physical violence behaviors among middle school students in Beijing / 中华流行病学杂志

Objective To described the prevalence of school physical violence behaviors and to explore its associated factors among middle school students in Beijing. Methods In 2009, a randomly selected cross- sectional survey was conducted among 5718 students in grades 7 to 12 in Beijing. A self-report anonymous questionnaire involving physical violence at school and sociodemographic variables, such as sex, grades, family economic status and family structure, peer relationships, and communication with their parents etc. were completed by students themselves.Logistic regression was used to estimate the association between physical violence and sociodemographic variables. Results Among the students, 14.3% reported that they had had physical violence behavior in school during the past 12 months. Male students had been more likely to have physical violence behaviors than female students (Male 25.2%, Female 5.1% ). For both male and female students, poor school cohesion were the risk factors of physical violence behaviors (Male OR=1.060, Female OR=1.065). For male students, factors as father' s lower education level (OR=1.653 ), remarried/single-parent families ( OR = 1.834 ), low-grade ( grade 7 OR = 5.291; grade 11 OR =1.526) , poor school performance (OR=1.470) etc were the risk factors of physical violence behaviors; while better-off family economic status (OR=0.546), good peer relationships (OR=0.618) , and easy to communicate with the father (OR=0.756) were the protective factors of physical violence behaviors. For female students, easy to communicate with her mother (OR = 0.358)were the protective factors of physical violence behaviors. Conclusion For male and female students, the prevalence of school physical violence and its related factors were different. Actions on prevention against physical violence behaviors should be fully considered, including factors as gender, personal characteristics, family, school and peers etc.

Familial clustering of obesity and the role of lifestyle factors among children in Beijing / 中华预防医学杂志

<p><b>OBJECTIVE</b>To investigate the correlation between lifestyle factors, parental obesity and adiposity in children, in order to provide theoretical evidence for public health policy establishment.</p><p><b>METHODS</b>A cross-sectional observation study was conducted among approximately 20 thousand children aged 2 - 18 years old in urban and rural regions of Beijing, by using stratified randomization clustering sampling methods. Familial environmental risk factors of children adiposity and parental obesity were assessed with standardized questionnaire. Anthropometric measurements, including height and weight, were conducted. SPSS 13.0 software was applied to analyze the data, including general description, chi(2) trend test and non-condition logistic analyse.</p><p><b>RESULTS</b>With IOTF obesity references, the prevalence of obesity in 21,198 children aged 2 - 18 years old was 5.6%. The behavioral characters (for example, smoking and drinking) and children obesity showed significant familial aggregation. In groups including "both parents not smoke", "only one parent smoke" and "both parents smoke", the smoking rates of offsprings were 1.50%, 2.93% and 6.01%, respectively (chi(trend)(2) = 107.009, P < 0.01). A similar pattern was found for offsprings' alcohol consumption rates (5.85%, 9.12% and 13.96%; chi(trend)(2) = 107.009, P < 0.01). Based on parents' BMI status, in groups including "both parents had normal weight", "father was obese", "mother was obese" and "both parents were obese", the prevalence of obesity in children were 3.29%, 11.48%, 9.12% and 27.01%, respectively (chi(trend)(2) = 293.404, P < 0.01). After controlling for sex and ages, factors such as physical exercises, sleeping times per day, fat intakes, watching TV, drinking alcohol were impact factors of children obesity. After controlling of confounding factors, such as children gender, age, birth weight, puberty, smoking history, drinking history, fat intakes, soft drink, physical exercises, education experiences of parents, smoking history, drinking history, family income and so on, maternal obesity had a greater influence on daughters than on sons (OR = 5.93, 95% CI: 3.57 - 9.84), and paternal obesity showed similar influence on sons (OR = 4.29, 95% CI: 3.21 - 5.72). Comparing to parents with normal weight, obese parents had more powerful impact on daughters (OR = 28.51, 95% CI: 15.13 - 53.72) than on sons (OR = 7.21, 95% CI: 4.07 - 12.75), regarding to 2 - 5 years group and 10 - 12 years group versus other age group (OR = 18.67, 95% CI: 1.49 - 234.46; OR = 22.25, 95% CI: 10.62 - 46.59).</p><p><b>CONCLUSION</b>Parental obesity is an independent risk factor of adiposity in children; gender and age affect this association. The lifestyle patterns of parents should have great impact on children. When prevention or intervention with children obesity, familial environmental factors should be emphasized.</p>

Family aggregation of primary hypertension among children and adolescents in Beijing / 中华流行病学杂志

Objective To explore the association between histories of hypertension in parents and level of blood pressure in their children so as to provide strategy for early intervention. Methods 19 088 children aged 6-17 years were selected in Beijing with stratified random cluster sampling method,and data on influencing factors including parental history of hypertension and other related environmental factors were collected.Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were examined.SPSS 13.0 was used for data analyses.Results The average prevalence of high blood pressure in children and adolescents was 9.13%based on the blood pressure criteria Beijing Children and Adolescents Metabolic Syndrome (BCAMS) set in 2004.Familial aggregation of hypertension in children and adolescents was observed (P＜0.001).There were positive associations between the numbers of parents with history of hypertension and both SBP and DBP of their offspring.Partial regression coefficients appeared to be 0.980 (95%CI:0.524-1.437) and 0.832 (95%CI:0.463-1.201) respectively,after controlling for con founding variables including gender,age,residential regions,body mass index (BMI),pubertal development,histories of smoking and drinking alcohol,fat intakes,physical exercises,parents' education level etc.Results from multiple factor logistic regression analysis showed that when compared with children whose parents did not have hypertension,the odds ratios of children having high blood pressure with only paternal history,only maternal history or with both parental histories were 1.688 (1.385-2.059),1.559 (1.164-2.087) and 1.273 (0.673-2.406),respectively,after adjustment for confounding factors.Conclusion Parental history of hypertension seemed to be an important independent risk factor for high blood pressure to their offspring.Heredity factors should be emphasized in the development of prevention and intervention on hypertension in children and adolescents.

Metabolic syndrome in overweight and obese schoolchildren in Beijing / 中华儿科杂志

<p><b>OBJECTIVE</b>To determine the prevalence and clinical phenotype of metabolic syndrome among overweight and obese schoolchildren in Beijing, and to compare the rates of diagnosis made according to the criteria of the National Cholesterol Education Program (NCEP) of the United States and International Diabetes Federation (IDF).</p><p><b>METHODS</b>Based on Beijing Child and Adolescent Metabolic Syndrome (BCAMS) study with body mass index (BMI), waist circumference (WC) and blood pressure measured, the overweight and obese children were screened among nearly 20 000 children 6-18 years of age in Beijing by Chinese BMI cutoffs for schoolchildren (7-18 years) and the US 2000 CDC Growth Charts--the 85th and 95th percentile (6 years) and were enrolled as the study population. Simultaneously a group of children with normal BMI were selected as the control group and based on the international method of age grouping, each of the above groups was divided further into 4 sub-groups in terms of age: 6-9, 10-12, 13-15 and 16-18 years old, respectively. Fasting plasma glucose (FPG) and insulin (FINS), serum high-density lipoprotein cholesterol (HDL-C) and triglyceride (TG) were examined. HOMA-IR index was calculated for estimating individual insulin resistance. A child who met any three or more of the following five criteria, according to NCEP definition, was diagnosed as MS. A diagnosis of MS using IDF definition required abdominal obesity plus any two or more of the other four criteria: (1) abnormal obesity: WC > or = P(90); (2) elevated BPs: SBP/DBP > or = P(90); (3) low HDL-C: HDL-C < 1.03 mmol/L (40 mg/dl); (4) high TG: TG > or = 1.24 mmol/L (110 mg/dl); (5) impaired fasting glucose (IFG): FPG > or = 5.6 mmol/L (100 mg/dl).</p><p><b>RESULTS</b>The prevalence rates of MS by NCEP definition were: 0.9%, 7.6% and 29.8% in the normal weight (control group), overweight and obese children, respectively, which were higher than the rates diagnosed by IDF definition with 0.1%, 5.2% and 28.6% in the three groups. The prevalence rates of individual MS component among obese children were: 81.6% for abnormal obesity, 47.7% for elevated BPs, 35.6% for high TG, 16.9% for low HDL-C, and 13.4% for IFG. Elevated BPs (29.8%), abnormal obesity (27.4%) and high TG (26.0%) were the leading three abnormalities among overweight children. With the increase of BMI, the clustering of MS components and insulin resistance (HOMA-IR) were remarkably increased. HOMA-IR significantly increased as the number of MS component increased.</p><p><b>CONCLUSIONS</b>MS has been in an epidemic status among the obese schoolchildren in Beijing. Abnormal obesity, elevated BPs and high TG were the three most common metabolic abnormalities for overweight and obese children. The prevalence rates of MS by NCEP definition in the present study was higher than those diagnosed by using IDF definition.</p>

Prevalence of overweight and obesity among children and adolescents in Beijing in 2004 / 中华流行病学杂志

<p><b>OBJECTIVE</b>To determine the current prevalence of overweight and obesity among children and adolescents (2-18 years) in Beijing and its distribution by age, gender and urban-rural residence.</p><p><b>METHODS</b>As part of the Beijing Child and Adolescent Metabolic Syndrome Study, a stratified cluster representative sample of 23,422 children aged 0-18 years was selected. Anthropometric measures including weight and height were collected from 21,198 subjects aged 2-18 years from April to October in 2004. Overweight and obesity were defined according to body mass index [BMI, weight(kg)/height(m2)] cutpoints. For national and international comparisons, three sex-age-specific BMI criteria were used:1) The BMI cutoffs recommended by the Chinese Working Group on Obesity for Children (WGOC) aged 7-18 years; 2) The US 2000 CDC Growth Charts (CDC 2000) frac 34, the 85th and 95th percentiles; 3) The International Obesity Task Force (IOTF) reference.</p><p><b>RESULTS</b>The overall combined prevalence of overweight and obesity was 18.6% with obesity as 8.1% based on the CDC 2000 criteria, The figures were 17.4% and 5.1% based on the IOTF criteria. According to the WGOC criteria, the combined prevalence of obesity was 20.9% and 8.9% in children aged 7-18 years. The combined prevalence was higher in school-age children (6-18 years) than in preschool-age children (19.8% vs. 14.8%, based on the CDC 2000 criteria). Among school-age children, the prevalence was higher in boys than in girls (26.7% vs. 16.5%), in urban than in rural areas (27.0% vs. 15.9%). However, these differences were not observed in preschool-age children. It was estimated that approximately 450 000 children from 2 through 18 years of age,were overweight or obesity in Beijing.</p><p><b>CONCLUSION</b>Data from our study indicated that one fifth of the children and adolescents in Beijing were under overweight or obesity situation which was the highest in the nation. Obesity among children and adolescents in Beijing had already become a serious public health problem which deserved greater attention.</p>

Nutrition and health status of the Beijing residents / 中华预防医学杂志

<p><b>OBJECTIVE</b>To investigate the constitution and health status of the Beijing residents, and the primary influencing factors on nutrition and health, as to finding out the epidemiological characters and the changing trend of chronic diseases and to establish scientific basis for the establishment of public health and disease prevention policies of Beijing.</p><p><b>METHODS</b>A stratified multi-stage cluster randomly sampling method was used. In total, 18 districts were surveyed, and among them, 9 were conducted dietary survey. The investigation was based on household, and all family members were surveyed at their home. After having got the compliance from the family members, question asking, medical examination, laboratory test and dietary investigation were carried out in these people.</p><p><b>RESULTS</b>The incidence rate of hypertension was 25.0% for the resident > or = 15 year-old, and over 50% for middle-aged and elderly people (> or = 45 years old). The incidence of diabetes for those not younger than 15 years old was 7.7%. The over-weight rate and the obesity rate for adults were 35.1% and 20.6%, respectively.</p><p><b>CONCLUSION</b>The following risk factors of chronic disease, such as unreasonable diet pattern, deficient intake of some micronutrients, over-weight and obesity, lack of physical examination, smoking and over-drinking, should be the important factors influencing the health of Beijing residents severely.</p>

Validation of lipids on body mass index reference recommended by Obesity Working Group, International Life Science Association of China / 中华流行病学杂志

<p><b>OBJECTIVE</b>To assess the relationship between overweight, obesity and blood lipid profiles of children and adolescents and to validate body mass index (BMI) cutoff points for overweight and obesity screening to Chinese children and adolescents, recommended by Working Group of Obesity, China (WGOC), International Life Science Association.</p><p><b>METHODS</b>2293 children and adolescents (1124 males and 1169 females), aged between 10 and 18 years, were randomly selected as samples from 6 schools in Beijing area. Fasting serum lipids including total cholesterol (TC), total triglycerides (TG), high density lipoprotein cholesterol (HDLC), thropometrical index as weight and height were measured. BMI equals to weight in kilograms were then divided by the square of height in meters.</p><p><b>RESULTS</b>According to BMI cutoff points recommended by WGOC, samples fell into 3 groups including normal group (BMI < 85 percentiles), overweight group (BMI >or= 85 and < 95 percentiles) and obesity group (BMI >or= 95 percentiles). Results clearly showed an increase of both serum TC and TG and a decrease of HDLC when BMI was increasing, among most age groups regardless of sex difference and the difference among BMI groups was statistically significant (P < 0.05 or P < 0.01).</p><p><b>CONCLUSIONS</b>Results of this study indicated that there was an obvious dose-effect relationship between BMI and lipid profiles which accounted for some rationality of the BMI cutoff points recommended by WGOC. The authors reckoned the findings important to managing relevant adult diseases during childhood, in China.</p>