Time Trends of Greenspaces, Air Pollution, and Asthma Prevalence among Children and Adolescents in India

Greenness and its composition and configuration in association with allergic rhinitis in preschool children

BACKGROUND

Few studies focus on the associations of green space composition and configuration with children's allergic rhinitis (AR).

METHODS

A multi-center population-based cross-sectional study was performed in 7 cities in mainland of China between 2019 and 2020, recruiting 36,867 preschool children. Information on the current AR symptoms and demographics were collected by questionnaire. Exposure to residential greenness was estimated by Normalized Difference Vegetation Index (NDVI, 1000 m buffer) around the residences. Greenness composition was estimated in 3 main categories: forest, grassland, shrubland. Configuration of each category and total greenness (a spatial resolution of 10 m × 10 m) was estimated by 6 landscape pattern metrics to quantify their area, shape complexity, aggregation, connectivity, and patch density. Exposure to daily ambient particulate matter (PM1, PM2.5 and PM10, a spatial resolution of 1 km × 1 km) was estimated. Multilevel logistic regression models were applied to analyze the associations of greenness and its composition and configuration with AR, and mediation effects by PMs were examined by mediation analysis models.

RESULTS

The prevalence of self-reported current AR in preschool children was 33.1%. Two indicators of forest, Aggregation Index of forest patches (AIforest) (odds ratio (OR):0.92, 95% Confidential Interval (CI): 0.88-0.97), and Patch Cohesion of forest (COHESIONforest) (OR: 0.93, 95% CI:0.89-0.98) showed significantly negative associations with AR symptoms. Mediation analyses found the associations were partially mediated by PMs. Age, exclusive breastfeed duration and season were the potential effect modifiers. The associations varied across seven cities.

CONCLUSION

Our findings suggest the inverse associations of the aggregation and connectivity of forest patches surrounding residence addresses with AR symptoms. Since the cross-sectional study only provides associations rather than causation, further studies are needed to confirm our results as well as the underlying mechanisms.

Global burden of pediatric asthma and rhinitis - what we have recently learned from epidemiology

PURPOSE OF REVIEW

To analyze and present recently published information on the factors that modify the burden of asthma and rhinitis in pediatric ages, such as ecological determinants; highlighting access and adherence to medications, exposure to pollutants and climate change. In addition to individual determinants such as obesity, protective & risk factors and comorbidities.

RECENT FINDINGS

Asthma and rhinitis continue to have a significant impact worldwide on the health of affected patients, primarily children. The burden of asthma is greatest in developing countries and vulnerable populations, resulting in increased morbidity, potentially preventable asthma deaths and socioeconomic consequences.

SUMMARY

A better understanding and representation of the burden of asthma and rhinitis in children can contribute to prevention strategies and improvements in the care of pediatric patients.