Prevalence and trends in obesity among China's children and adolescents, 1985-2010

Evidence for contemporary arterial stiffening in obese children and adolescents using pulse wave velocity: A systematic review and meta-analysis

INTRODUCTION

Pulse wave velocity (PWV) and augmentation index (AI) may provide information on future cardiovascular risk. Reports are conflicting on whether obese children show evidence of raised PWV and AI.

METHODS

Systematic review and meta-analysis of published studies using EMBASE, Web-of-Science and PUBMED databases for studies reporting PWV and AI in obese versus non-obese controls(<age 18 years). Studies were pooled in meta-analyses to generate weighted mean differences (WMD) using random effects methodology. Analyses were repeated by method, quality grade and anatomical region.

RESULTS

383 studies were found in initial searches and 81 were assessed in detail; 14 studies (6677 total participants, 1120 obese and 5557 non-obese) were suitable for meta-analysis for PWV, and 5 studies (728 participants obese and 317 non-obese) for AI. Across all studies, obese children had higher PWV than non-obese children (WMD 0.45(95% confidence interval 0.10 to 0.81 ms(-)(1))). This difference was not significant when only studies with low/medium risk of bias were included. Obese subjects had higher PWV measured directly at the carotid (WMD 0.51 (0.35-0.67 ms(-)(1))) and aorta (WMD 1.33 (0.36-2.31)). No significant differences were found for AI. Heterogeneity was high in all analyses(I(2) > 90% in PWV and AI meta-analyses).

CONCLUSION

There is moderate evidence that obese children have increased arterial stiffening, especially in central arteries. This supports concerns about future CVD risk in obese children. Developing effective obesity interventions must remain a health priority.

The association between sleep patterns and overweight/obesity in Chinese children: a cross-sectional study

OBJECTIVE

This study evaluated the association between sleep patterns and the risk of being overweight/obese in Chinese children.

METHODS

A total of 3,086 children (1,608 boys and 1,478 girls) between 7 and 14 years of age and studying in primary schools were recruited as eligible study participants in this study. We collected the information about children regarding sleep patterns, body height and weight, insomnia, healthy status, time allocation of daily activities, and demographic characteristics using a parental-reported questionnaire.

RESULTS

Overweight/obese children were younger, predominantly male, and more prone to have suffered from illness in the past 12 months compared to normal-weight peers. They were also less prone to compensate for sleep deficits during weekends (47.6% vs 39.1%; χ (2)=11.637, P<0.001) and holidays (52.0% vs 42.0%; χ (2)=16.057, P<0.001). Sleep duration on weekdays did not affect the risk of being overweight/obese. The adjusted odds ratios for overweight/obesity (noncompensated) group using the compensated group as a reference were 1.197 (95% confidence interval [CI]: 1.004-1.493) during weekends and 1.309 (95% CI: 1.052-1.630) during holidays.

CONCLUSION

Compensation for sleep deficits on non-weekdays may ameliorate the risk of being overweight/obese in Chinese children. Moreover, no significant association between the risk of being overweight/obese and sleep duration on weekdays was demonstrated in the current study, which may be due to pervasive sleep insufficiency on weekdays in Chinese children.

A longitudinal analysis of the effects of socioeconomic factors, foreign media, and attitude toward appearance on general and central adiposity in Chinese adolescents

This paper explores the longitudinal effects of socioeconomic factors (i.e., parent education and family income level), foreign media, and attitude toward appearance on general and central adiposity among Chinese adolescents.

A longitudinal analysis was performed using data from the China Seven Cities Study, a health promotion and smoking prevention study conducted in seven cities across Mainland China between 2002 and 2005. Participants included 5,020 middle and high school students and their parents. Explanatory variables included foreign media exposure, attitude toward appearance, parent education, and family income. Three-level, random-effect models were used to predict general adiposity (i.e., body mass index) and central adiposity (i.e., waist circumference). The Generalized Estimating Equation approach was utilized to determine the effect of explanatory variables on overweight status.

Among girls, foreign media exposure was significantly negatively associated with general adiposity over time (β = − 0.06, p = 0.01 for middle school girls; β = − 0.06, p = 0.03 for high school girls). Attitude toward appearance was associated with lesser odds of being overweight, particularly among high school girls (OR = 0.86, p < 0.01). Among boys, parental education was significantly positively associated with general adiposity (β = 0.62, p < 0.01 for middle school boys; β = 0.37, p = 0.02 for high school boys) and associated with greater odds of being overweight (OR = 1.55, p < 0.01 for middle school boys; OR = 1.26, p = 0.04 for high school boys). Across all gender and grade levels, family income was significantly negatively associated with central adiposity over time.

Interventions addressing Chinese adolescent overweight/obesity should consider these factors as potential focus areas.

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Foreign media exposure decreases BMI over time among girls.

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Girls placing importance on appearance have lesser odds of being overweight.

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Boys have greater odds of being overweight with high parent education.

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High family income was negatively associated with central adiposity.

Secular trends in prevalence of overweight and obesity among adults in rural Tianjin, China from 1991 to 2011: a population-based study

Objectives

Obesity is associated with cardiovascular diseases and has become the main public health issue in western countries and urban China. However, the prevalence and secular trends of obesity in rural China are currently unknown. The aim of this study was to investigate secular trends in the prevalence of overweight and obesity among rural adults in northern China between 1991 and 2011.

Method

The prevalence of overweight and obesity was assessed in adults aged 35–74 years living in a rural area in northern China by comparing two surveys that were conducted in 1991 and 2011, respectively.

Result

The age-adjusted prevalence of overweight increased from 24.5% in 1991 to 42.0% in 2011, and the prevalence of obesity increased from 5.7% in 1991 to 19.6% in 2011. Over the 21-year period, there were significant increases in the prevalence of overweight and obesity for both men and women in all age groups; however, the greatest increase was observed in men aged 35–44 years, with an 10.3-fold increase in obesity prevalence. The prevalence of obesity increased significantly in all risk factors categories, including education levels, blood pressure categories, diabetes previous history, current smoking situation and alcohol drinking situation over the past 21 years overall (p<0.05). The greatest increase in obesity prevalence appeared among those who consumed alcohol (increased by 8.0-fold). Next, there was a 5.3-fold increase in the prevalence of obesity in illiterate residents.

Conclusion

The prevalence of overweight and obesity has increased rapidly among rural adults in Tianjin over the past 21 years, with the most dramatic increase observed in young men. Therefore, the burden of obesity should serve as a call for action.