Prevalence and associated factors of overweight in Chinese adolescents: A cross-sectional study

Obesity has been a global public health issue due to the increasing mortality rate and prevalence among children. However, there are scarce studies on obesity prevalence in Hong Kong children. The study aims to identify the risk factors of obesity among primary and secondary school students by assessing the relationship between sociodemographic factors, health-related behaviors, and social relationships.

Self-administrated surveys were collected from 30 primary schools and 25 secondary schools participating in the "Quality Education Fund Thematic Network on Health Schools" project. Descriptive analysis was conducted to examine the proportions of different characteristics and to compare the disparity between primary and secondary school students with obesity.

A total of 4884 responses were collected. A larger proportion of primary school students with obesity were male (adjusted odds ratio [aOR]: 2.55, 95% confidence interval [CI]: 1.77-3.67, p < 0.001) and actively gamed (aOR: 1.64, 95% CI: 1.07-2.51, p = 0.024). Secondary school students with obesity were male (aOR: 1.61, 95% CI: 1.21-2.13, p = 0.001), had poor self-perceived academic performance (aOR:1.51, 95% CI: 1.10-2.08, p = 0.011) and expressed higher life satisfaction (family) (aOR: 1.13, 95% CI: 1.01-1.26, p = 0.032). There were negative associations found between obesity and physical activity, high consumption of sugary drinks, chocolate or candies, and insufficient consumption of vegetables.

Male sex, physical inactivity, low self-perecived academic performance, and poor dietary behaviors were the risk factors for obesity among primary and secondary school students. The findings highlighted the importance of identifying younger individuals who were at risk of becoming clinically obese. Further studies should explore the effectiveness of various interventions through longitudinal study.