The association among SES, screen time, and outdoor play in children at different ages: The GECKO Drenthe study

Adherence to physical activity and screen time recommendations of youth: Demographic differences from National Health and Nutrition Examination Survey 2017-2018

Background

Engaging in physical activity (PA) and reducing sedentary behaviors among youth are linked to improved mental and physical health. This study aimed to examine demographic differences among youth adhering to PA and Screen Time (ST) recommendations.

Methods

The present study utilized data from the 2017-2018 National Health and Nutrition Examination Survey (NHANES). The NHANES survey employed a cross-sectional design and gathered information on the daily duration of moderate-to-vigorous PA lasting 60 min or more, as well as the maximum daily ST not exceeding 2 h. The analysis encompassed a total of 1697 youth aged between 6 and 17 years.

Results

Overall, 36.3% of participants adhered to PA recommendations, 20.9% adhered to ST recommendations and 10.8% of youth met both recommendations. The odds of meeting PA, ST and both recommendations were inversely associated with obesity (obese vs. normal: aOR, 0.56 [95% CI, 0.42-0.75]), (aOR, 0.67 [95% CI, 0.48-0.94]) and (aOR, 0.51 [95% CI, 0.32-0.82]) respectively, and age (14-17 years vs. 6-9 years: aOR, 0.2 [95% CI, 0.15-0.27]), (aOR, 0.33 [95% CI, 0.23-0.47]) and (aOR, 0.16 [95% CI, 0.09-0.3]) respectively.

Conclusion

A small portion of the youth met PA and ST recommendations. Older youth, youth with obesity, and youth with a parent or guardian who had not completed a high school education were particularly at risk.

Socioeconomic disparities and green space associated with myopia among Chinese school-aged students: A population-based cohort study

Background

There is increasing evidence on the link between environmental factors and myopia in children and adolescents, yet with inconsistent conclusions. We investigated the associations between socioeconomic inequalities and green space with myopia in school-aged students participating in the Tianjin Child and Adolescent Research of Eye (TCARE) study.

Methods

We obtained data from a population-based dynamic cohort study conducted in Tianjin, China, in 2021 and followed up in 2022. We included 1 245 271 participants from 16 districts with an average age of 11.6 years (standard deviation = 3.3) in our analysis. We synthesized their area-level SES through a prediction model that combined economic, educational, and health care variables and assessed the greenness levels surrounding the school using the Normalized Difference Vegetation Index (NDVI) based on data obtained through satellite remote sensing. We performed generalised linear mixed effects analyses for each myopia outcome separately, with adjustments for students' sex, years of education completed, and the school's geographical location.

Results

We observed that students living in low SES areas had the highest prevalence of myopia (60.7%) in the last screening in 2022, as well as a higher incidence of one-year myopia (26.4%) compared to those residing in middle SES areas (22.7%). With a 0.1 increase in the 250, 500, and 1000 m buffer NDVI, the prevalence of myopia dropped by 6.3% (odds ratio (OR) = 0.937; 95% confidence interval (CI) = 0.915, 0.960), 7.7% (OR = 0.923; 95% CI = 0.900, 0.946), and 8.7% (OR = 0.913; 95% CI = 0.889, 0.937), respectively. The interaction analysis showed that low SES and low greenness exacerbate the prevalence of myopia. Findings from longitudinal analyses consistently demonstrated a correlation between higher values of NDVI and a slower progression of myopia. These findings remained robust across sensitivity analyses, including for variables on parental myopia and students' behaviors.

Conclusions

Exposure to green spaces could play a crucial role in slowing the progression of myopia among school-aged students. Myopia control policies should prioritise young populations residing in low SES areas with limited access to green spaces, as they face the highest potential risks.

Association between preschooler outdoor play and home yard vegetation as measured by high resolution imagery: Findings from the PLAYCE study

Outdoor play in the home yard is an important source of physical activity for many preschoolers. This study investigated if home yard size and vegetation are related to preschooler outdoor play time. High-resolution remotely sensed data were used to distinguish between types of vegetation coverage in the home yard. Shrub and tree cover, and yard size, were positively associated with outdoor play. Following stratification by socio-economic status (SES - parent education), only tree cover was positively associated with preschooler outdoor play in low SES households. All types of vegetation cover were positively associated with preschooler outdoor play in higher SES households. This study highlights the importance of larger yard sizes and higher levels of vegetation for facilitating outdoor play in preschoolers.