Prevalences Of Overweight And Obesity And Their Risk Factors Among Schoolchildren And Adolescentin Tianjin

There is an increasing trend for development of overweight and obesity in children and adolescents all over the world. It is estimated that more than 10% of the world's school-aged children are overweight and obesity where a quarter for obesity in 2004. The situatioin is almost the same in China.Objective:To investigate the prevalences of overweight and obesity and their influencing factors among school children in Tianjin.Methods:A cross-sectional study to the 6～18 years old students was conducted.The multi-phasic stratified cluster sampling method was used. First of all, we got 2 strata, urban and suburb. Then all the districts were divided into four levels according to the GDP. One district was selected from each GDP level and one school was selected randomly by random digital table. Finally students from 5 schools were selected as the study population Univarite Logistic regression analysis, principal component analysis and factor analysis were used to analyse the risk factors of overweight and obesity.Results:1671 students were investigated,805 of male (48.17%) and 866 of female (51.83%). The total prevalence of overweight was 15.32%,17.01% for male and 13.74% for female. The total adjusted prevalence was 14.77%,15.48% for male and 14.16% for female respectively. The total prevalence of obesity was 18.55%,22.48% for male and 14.90% for female respectively. The adjusted prevalence of obesity was 17.26% for all,20.60% for male and 14.37% for female respectively.Logistic regression analysis of overweight and obesity showed that the risk factors included high level of education of parents; higher intake of staple food, poultry, meat and egg; cesarean section; mother's history of gestational diabetes mellitus, gestational hypertension and high ratio of gain weight during pregnancy; overnutrition of students; puberty was started; overweight and obesity of parents; family history of diabetes mellitus and cardiovascular diseases.The preventive factors included gender of girl; older age of students; live in suburb; physical work for parents; higher total income of family; interesting in sports; take part in outdoor sports; take part in sports more often; do physical practice for longer time; intake more fruit, bean and sweet food; anaemia of mother during pregnancy.According to the Factor Analysis, synthetical factor (included resident place, educational level of parents, mode of delivery and high ratio of gain weight during pregnancy) (OR=1.847,95%CI:1.482～2.301); the weight factor of parents (OR=1.610,95% CI:1.305～1.988); overnutrition of students (OR=1.344,95% CI: 1.083～1.668) were risk factors. Sport factor (OR=0.722,95% CI:0.584～0.893); age and puberty factor (OR=0.811,95% CI:0.659～0.999) and high total income of family factor (OR=0.718,95%CI:0.582～0.885) were the preventive factors.Logistic regression analysis of obesity showed that the risk factors included high level education of parents; more often for repast times per day; higher intake of staple food, poultry, meat; cesarean section; high ratio of gain weight during pregnancy; overnutrition of students; puberty was started; overweight and obesity of parents; family history of diabetes mellitus and cardiovascular diseases.. The preventive factors included gender of girl; older age of students; live in suburb; physical work for parents; take part in the sport outdoor; take part in the sport more often; do physical practice for long time; long sleeping time and anaemia of mother during pregnancy.According to the factor analysis, synthetical factors included resident place, educational of parents and mode of delivery, OR=1.827,95% CI:1.443～2.315; family history of chronic disease factor(OR=1.288,95% CI:1.019～1.629); the weight of parents factor (OR=1.390,95% CI; 1.110～1.739); sex and rice intake factor (OR=1.305,95%CI:1.044～1.632); overnutrition of students (OR=1.598,95% CI: 1.244～2.054) and more often for repast times per day (OR=1.293,95% CI: 1.008～1.658) were risk factors. Age and puberty factor (OR=0.643,95% CI: 0.510～0.810); sport factor (OR=0.748,95% CI:0.593～0.943); physical work for parents factor (OR=0.761,95%CI:0.613～0.945) were the preventive factors of obesity.Conclusion:The prevalences of overweight and obesity among schoolchildren are higher than average prevalence in our country. The prevalence of obesity is more than overweight. Multi-factor analysis showed that risk factors of abnormal weight of students included: live in urban districts; high level of education of parents; cesarean section; overweight and obesity of parents and overnutrition of students. The preventive factors included older age of students; puberty was started and do physical practice. According the point of genetic factor, the abnormal weight of parents do increase the probability of the students suffer from overweight or obesity, but to the students who are overweight or obesity, do less sport, eat more and other unhealthy behaviour which caused by the better economic life make a stronger effect on them.