Prevalence o f Overw eigh t and Obesity am ong Studen ts Aged 7-22 Years in Jiangsu Province, China＊

Taha Hussein Musa, WEI Li, LI Xiao Shan, PU Yue Pu, and WEI Ping M in,#

1. Department of Epidemiology and Biostatistics, School of Public Health, Southeast University, Nanjing 210009, Jiangsu, China; 2. Department of Infectious Disease Prevention and School Health, Nanjing Municipal Center for Disease Control and Prevention, Nanjing 210009, Jiangsu, China; 3. Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing 210009, Jiangsu, China

Original Artic le

Prevalence o f Overw eigh t and Obesity am ong Studen ts Aged 7-22 Years in Jiangsu Province, China＊

Taha Hussein Musa1,^, WEI Li2,^, LI Xiao Shan1, PU Yue Pu3,#, and WEI Ping M in1,#

1. Department of Epidemiology and Biostatistics, School of Public Health, Southeast University, Nanjing 210009, Jiangsu, China; 2. Department of Infectious Disease Prevention and School Health, Nanjing Municipal Center for Disease Control and Prevention, Nanjing 210009, Jiangsu, China; 3. Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing 210009, Jiangsu, China

ObjectiveTo report the prevalence and trend of overweight and obesity among students aged 7-22 years in Jiangsu, 2010 to 2013.

MethodsThis cross-sectional study was carried out as part of students physical fitness and health survey in Jiangsu province. A total of 255,581 subjects (50.03% males and 49.97% females) enrolled in 82 school and 10 universities in Jiangsu. Weights and heights were obtained for each subject and its body mass index (BMI) was calculated using the Chinese Working Group on Obesity in China (CWGO).

ResultsAnthropometric measurement including bodyweight, height, BM I and bust were significantly different between males in urban compared to females living rural areas (P＜0.001). The total prevalence of overweight and obesity was 12.4% and 5.7%. Males had a significantly higher rate than in female's student. The prevalence of overweight and obesity by age groups was (14.5%, 10.3%) at age 7-11 years, (11.2%, 6.8%) at age 12-14 years, (11.7%, 3.1%) at age 15-17 years, and (11.4%, 2.3%) at age 18-22 years. By regions; the highest prevalence of overweight obesity reported in Taizhou (10.0%, 14.2%), Xuzhou (9.4%, 12.5%), and Nanjing (9.2%, 15.6%), respectively.

ConclusionThe finding declares that overweight and obesity are important health problems among students in Jiangsu Province. Early intervention programme are needed to address this problems.

Body mass index (BM I); Anthropometric measures; Overweight; Obesity; Jiangsu Province; China

www.besjournal.com (full text)CN: 11-2816/QCopyright ?2016 by China CDC

INTRODUCTION

Overweight and obesity among young people is a growing concern of public health[1], and is associated w ith both physical and psychological health consequences. Currently, the rate of obesity has increased significantly during the last decades in many countriesamongchildrenandadolescents. Therefore, development of more research involving overweight and obesity, particularly in children at school age were essential to monitor the healthstatus in the community[2-4]. high among urban school children and adolescent[1,5].

Obesity and overweight are seen exceptionally Therefore, child health and grow th status is globally recognized as an important indicators for child health standards[6]. Obesity has negative health consequences among populations and is a major risk factor for common diseases such as cardiovascular, stroke, diabetes and cancer[7-8].

In particular, obesity was reported to be associated w ith many diseases such as development of hypertension, diabetes mellitus, coronary heart disease, certain forms of cancer, and sleep-breathing disorders[9]. Obesity was also confirmed to be associated w ith high blood pressure (HBP) rate due to increasing the body mass index, while both systolic and diastolic blood pressure were positively related to the body mass index, and the association between obesity and HBP remained statistically significant after adjustment of age, heart rate, smoking, alcohol intake, and physical activity[10]. Furthermore, obesity prevalence is also rapidly increasing among children and adolescents[11]although many researchers believed it in the past to be less frequently associated with increased morbidity than in adults. Obesity in children is now recognized to be associated w ith insulin resistance, hyperliem ia, hepatic steatosis, sleep apnea and orthopedic complication[12-13], in adults BMI was seen to be strongly associated w ith body fats and the risk increased mortality[14]. Obesity was reported as to be a major contributing factor to the decline of levels of physical fitness, and the increase in risk of chronic diseases and mortality rates[15].

In China approximately 260 m illion are overweight or obese adults w ith 30% prevalence, 50% of obese individuals are in major cities. The fast grow th of the national economy in the past decades, the nutritional status of the Chinese people has improved greatly, but main dietary problems still exist such as iron deficiency[16]. However, there are still huge differences between urban and rural areas in the past several decades. Stunting was as high as 30.2% and it was the most serious problem impeding child grow th and development[17-18]. A study by Australian University students showed that 1 in 4 Australians were classified as obese in 2011-2012[19]. In Italy and Sudan the prevalence (where it is high/low) of BM I among the age groups 11-15 years-old were observed[20-21].

A study conducted in 2003 among students aged 12-14 years from eight schools in Jiangsu Province, indicated over-nutrition as the problems due to food habits and student lifestyle. The rate of overweight and obesity were increased in schools children in Jiangsu, China[22]. Study among College students between 2009-2011 in Hebei province found that the standard rate of height and weight was quite low and the number of overweight male students was higher than that of females in the same study area[23]. However, previous large epidem iological studies indicated that about one-fifth of the one billion overweight or obese people around the world are Chinese. Therefore, the aim of the present study was to provide the most recently evaluated rates of body weight, height, BMI, bust, and prevalence of overweight and obesity in 7-22 years-old among students living in 13 cities in Jiangsu province, China, during the period from 2010 to 2013.

MATERIALS AND METHODS

Population-based cross sectional study was conducted among students in Jiangsu province, China. During physical fitness and health surveillance from 2010 to 2013.

The study was conducted in Jiangsu province in southeast China. It covers an area of approximately 1 m illion km2and has a population of 73.55 m illion, which represents the highest population density in China. It is one of the wealthiest provinces; however, the econom ic status varies greatly according to regions.

Research data was obtained from Jiangsu Provincial Department of Education in Nanjing research units. A total of 255,581 subjects (127,866 male and 127,715 female) aged 7-22 years were recruited in this study from 82 primary, m iddle and high schools, and 10 provincial universities. Students were subdivided by gender, age groups (7-11, 12-14, 15-17, and 18-22 years), living status (urban and rural) and three socio-econom ic regions including North Jiangsu (Huai'an, Lianyungang, Suqian, Xuzhou, Wuxi, and Yancheng), South Jiangsu (Changzhou, Nanjing, Suzhou, Zhenjiang) and Central Jiangsu (Yangzhou, Nantong, Taizhou).

Anthropometric Measurements

Self adm inistrated questionnaire was used to collect information on socio-demographic indicators and anthropometrics measurements were carried out by well-trained health workers who followed a reference protocol. While the equipment tool was calibratedbeforestartsanthropometricsmeasurements. Briefly, fasting body weight was measured to the nearest 0.10 kg using a beam balance scale (RGT-140, Weighting Apparatus Co.Ltd. Changzhou Wujin, China) w ith subjects wearing light weight clothing. Height 0.01 m was measured w ith a portable stadiometer while the subjects in standing position, without shoes[3]and bust was measured by elastic tape.

All instruments were of Chinese origin and were calibrated regularly. Observers who followed standardizedproceduresweretrainedand supervised by the Centers for Disease Control and Prevention (CDC) in the 13 cities of Jiangsu province. All study investigators and staff members successfully completed a training program before data collection on study aim, especially trained for anthropometric skills on taken anthropometric, filling questionnaire in research objectives, used of specific tools and methodologies for measuring body weight and height and using the standard techniques for anthropometric measurements. Data collection relies on double-checking w ith existing rules and guide line from Centers for Disease Control and Prevention. Two students from each city were participated in entering data in SPSS sheet. formula weight (kg)/height2(m)2. BM I classification

Body mass index was then computed using reference proposed by Chinese Working Group on Obesity in China (WGOC) was used to as screening reference to calculate the prevalence and trend of overweight and obesity in these groups[24]. The study approved by local ethic comm ittee of student's health literacy promotion and research, Jiangsu province and the Institutional Review Board of the School of Public Health.

Statistical Analyses

Descriptive statistics were calculated and presented as mean (SD), and Chi-Square test, independent sample t-test, and one-way analysis of variance was used to evaluate differences within gender and age group. Statistical analyses were performed by using IBM SPSS version 20.0 (SPSS, Inc, Chicago, IL, USA). The level of significance was set at (P＜0.05).

RESULTS

This cross-sectional study was conducted to assess the trend prevalence of overweight and obesity in among students aged 7-22 years in Jiangsu province, China during the period 2010-2013. A total of 255,581 subjects (127,866 males and 127,715 female) aged 7-22 years were enrolled in to the study and completed the anthropometric measurements. A total 126,957 from rural area and 128,624 from urban area. The subjects were classified into different socio-econom ic regions (North Jiangsu, South Jiangsu and central Jiangsu Province), and 46.59% subjects were from South Jiangsu province, 30.53% North Jiangsu and 22.88% from central Jiangsu province as given in Table 1.

The descriptive statistics of anthropometric measurements for study population are shown in Figure 1 which highlight the students average (SD) of body height 1.57 m, body weight 49.89 kg, BMI 19.66 (3.25) kg/m2, and bust 76.88 cm respectively for both male and female. The anthropometric measurements were significantly different (P＜0.001) between male and females. The average body height, weight, BMI and bust were significantly (P＜0.001) increased among males compared to females.

Table 2, shows that the mean height, weight, BMI and bust for male students living in the urban area were 1.67 m, 54.71 kg, 20.40 kg/m2, and 79.02 cm, respectively, and those living in the rural one were 1.60 m, 52.37 kg, 19.84 kg/m2, and 77.44 cm, respectively, the mean height, weight, BMI, and bust for female students' lives in urban area were 1.54 m, 46.84 kg, 19.32 kg/m2, and 75.94 cm, respectively, and those live in the rural one were 1.53 m, 45.65 kg, 19.09 kg/m2, and 75.14 cm, respectively. The anthropometrics measurements were shown to be higher for male students living in the urban and rural areas compared to female students living in the same places.

Table 1. Demographic Characteristics of Study

The prevalence of overweight and obesity were (14.5%, 10.3%) at age 7-11 years, (11.2%, 6.8%) at age 12-14 years, (11.7%, 3.1%) at age 15-17 years, and (11.4%, 2.3%) at age 18-22 years. Obesity was shown decrease w ith increasing age groups as presented in Figure 3.

The results shows a high prevalence of overweight in Nanjing, Yancheng, Taizhou, and Yangzhou, 15.6%, 14.5%, 14.2%, and 13.5%, respectively. On the other hand, Nantong and Suzhou reported the same prevalence of overweight (12.7%). Obesity rate was high in Taizhou, Nanjing, Xuzhou, and Yangzhou (10.0%, 9.2%, 9.4%, 8.5%), respectively, and sim ilar rates were reported in Yancheng and Suqian (8.2%), as well as Nantong, Zhenjiang and Suzhou (5.3%). A lower prevalence of obesity was observed among students in Huai'an (4.7%) compared to others districts as shown in Figure 4.

The prevalence of overweight and obesity among students in 2010, 2011, 2012, and 2013 are shown in Table 3. A higher prevalence of overweight and obesity among students were observed in the years 2012 and 2013.

There is a significant change in overweight and obesity prevalence in school children and adolescents from 2010 to 2013. However, the prevalence of overweight and obesity remains high in males compared to female students. For males, the pattern was different, w ith 8.6%, 6.4%, 8.1%, and 8.0% obese, respectively whereas for females 3.6%, 3.0%, 3.5%, and 3.9% during the period 2010, 2011, 2012, and 2013, respectively.

One important noticed in this study is variances for prevalence of overweight and obesity by sex, living status and year. As seen in Table 4, the trend observed in Jiangsu, indicates a continues double increasing in overweight and obesity prevalence in males com pare w ith females students during the four years.

By the region also there is remarkable increasing in urban children compare w ith rural students in Jiangsu Province. These differences were statistically significant (Chi-square test, P＜0.001) as were showed in Table 4.

Until recently health consequences of obesity among Chinese people have seen continuously increasing in children and adolescents, although the health care system in China has significantly improved, moving towards universal health coverage[3].

The prevalence of overall normal weight, overweight and obesity were (81.9%, 12.4%, and 5.7%),respectivelyamonglargemultistage cross-sectional studies with 255,581 students during the four years survey. Overweight and obesity was found higher among males students compared w ith females students, it was sim ilar to the previous studies in Chongqing[29], and Shenzhen[30]. The prevalence of pediatric obesity in rural China was relatively increasing in children and adolescent in the 7-18 age group, and the percentage for overweight and obesity was (15.4%, 6.4%), respectively. Current study revealed the prevalence of overweight and obesity was higher in urban students than rural areas[3,19]. Overweight among Chinese students was lower than Egyptian students and Sudanese schoolchildren aged 15-18 years, while obesity in Chinese student was higher than Egyptian and Sudanese students[21,25]. Incidence was found to be lower than the United states in children aged 5 to 14 years by 11.9% for obesity rate, and within gender (10.1%) for girls and 13.7% for boys[31]. Student prevalence rates were lower than the data from 2007-2008NationalHealthandNutrition Exam ination Survey (NHANES) in the United States among all children aged 2-19 years. In Italy, the city of Sicily shows a high result for obesity compared to current rates[15]. Overweight (15.3%) and obesity (3.5%) were different among 18-24 years-old female students in Poland[32]. In Cyprus city, obesity prevalence was (8.1%) in 2010 compared w ith (5.9%) in 2000, which was higher than students in Jiangsu province[33].

By living condition overweight and obesity in males living in urban and rural areas was sim ilar to the conclusive data obtained by Dong, et al.[27]. However, the overweight and obesity rates among students in Jiangsu province were higher than students in Shandong province[27], and lower than those reported in the China National Nutrition and Health Survey conducted in 2005[34].

This study showed a significantly higher proportion of obese and overweight children in northern, southern and central Jiangsu area compared to other studies. There are several potential explanations for the variation. First, compared to the previous study, the subjects were all located in the eastern- central coastal of the People's Republic of China characterized as a more develop site based on Human development index, with rapid econom ic development in China. As a result, the Chinese living environment, dietary habits and lifestyle of the population were continuously improved than before. The culture of Western-style food has become increasingly available in recent years. The Chinese now consume fewer staple foods and more meat and particularly dairy products than previously[35]. Evidence of increasing fast service restaurants in the cities such as Kentucky Fried Chicken (KFC) and McDonalds, which are popular among children especially in big cities, have strangely increased dietary fat intake in children, adolescents and adults[36]. The increased obesity is associated with the better socioeconom ic status and intense process of urbanization and less active lifestyles[36]. A second observation likely to come from previous findings have reported behavioral risk factor in spending time media use such as watching television, less physical activity were increase the increased body mass Index level[37-38].

The worldw ide prevalence of childhood overweight and obesity increased from 4.2% (3.2%, 5.2%) in 1990 to 6.7% (5.6%, 7.7%) in 2010. This trend is expected to reach 9.1% (7.3%, 10.9%). The estimated childhood overweight and obesity in Africa in 2010 was 8.5% (7.4%, 9.5%) and is expected to reach 12.7% (10.6%, 14.8%) in 2020. The prevalence is lower in Asia (4.9% in 2010) than in Africa, however, the number of affected children (18 m illion) is higher in Asia.

The prevalence of overweight and obesity were reported higher rate in urban area compare w ith rural area of Jiangsu province. This may return back to the fast developing of socioeconom ic status of the population in Jiangsu province, geographic and climate change conditions as well as dietary habits play a roles in increasing the rate of over weight and obesity, in addition to students behavioral and lifestyle which may contribute in increasing the prevalence of overweight and obesity among students in Jiangsu province.

Although prevalence estimates provide evidence on the burden of overweight and obesity, the incidence is the key to understand the risk over a life time and monitor the health status of students in Jiangsu province. The identification of the potential age for intervention will promote a good healthstatus relating overweight and obesity. The present age study w ill add great value in medical anthropometry research and allow for monitoring the trend of overweight and obesity among students in future.

In conclusion, there have been a significant changes in overweight and obesity prevalence in students from 2010, 2011, 2012, and 2013. However, the prevalence remains higher rate among males' students compared with females. The prevalence of overweight and obesity rate was higher in urban compared with rural area. Although the obesity is still endem ic in China, it may reduce through the evidence-based interventions. Therefore, more efforts are needed towards this to achieve the goal, maintain normal body weight. The intervention programme should focus on changing student's lifestyle behavioral in Jiangsu province, practicing physical activity, may contribute in reducing the prevalence of overweight and obesity among students in Jiangsu province.

DECLARATION OF CONFLICTING INTERESTS

The authors declared no potential conflicts of interest w ith respect to the research, authorship, and/or publication of this article.

AUTHORS' CONTRIBUTIONS

T H M drafted the manuscript. W L contributes in data analysis and L X revised the manuscript in detail P Y and W P provided a technical observation on data and project backgrounds.

Accepted: October 1, 2016

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Biomed Environ Sci, 2016; 29(10): 697-70510.3967/bes2016.094ISSN: 0895-3988

*This work was fully supported by the Jiangsu Provincial Social Science Foundation Grant (3TYA001).

^These authors contributed equally to this work.

#Correspondence should be addressed to Prof. PU Yue Pu and WEI Ping Min, Tel: 86-25-83243899, Fax: 86-21-64338864, E-mail: yppu@seu.edu.cn & mpw1963@126.com

Biographical notes of the s: Taha Hussein Musa, male, born in 1978, PhD student, majoring in epidemiology and biostatistics; WEI Li, male, born in 1984, MSc degree, majoring in infectious disease prevention.

July 27, 2016;