Respiratory health effects of residential individual and cumulative risk factors in children living in two cities of the Pearl River Delta Region, China

Jianqing Lin; Weiwei Lin; Zixuan Yin; Xi Fu; Dejian Mai; Shaojie Fu; Junfeng Jim Zhang; Jicheng Gong; Ning Feng; Lingyan He

doi:10.21037/jtd.2020.03.92

Respiratory health effects of residential individual and cumulative risk factors in children living in two cities of the Pearl River Delta Region, China

J Thorac Dis. 2020 Oct;12(10):6342-6355. doi: 10.21037/jtd.2020.03.92.

Authors

Jianqing Lin¹, Weiwei Lin¹, Zixuan Yin², Xi Fu¹, Dejian Mai¹, Shaojie Fu¹, Junfeng Jim Zhang^{3

4

5}, Jicheng Gong⁶, Ning Feng², Lingyan He²

Affiliations

¹ Department of Occupational and Environmental Health, School of Public Health, Sun Yat-Sen University, Guangzhou 510080, China.
² Key Laboratory for Urban Habitat Environmental Science and Technology, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China.
³ Nicholas School of Environment & Duke Global Health Institute, Duke University, Durham, USA.
⁴ Duke Kunshan University, Kunshan 215316, China.
⁵ Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou 510120, China.
⁶ Beijing Innovation Center for Engineering Science and Advanced Technology, State Key Joint Laboratory for Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, and Center for Environment and Health, Peking University, Beijing 100871, China.

Abstract

Background: Indoor environment is complex, with many factors potentially interacting with each other to affect health. However, previous studies have usually focused on effect of a single factor. Assessment of the combined effects of multiple factors can help with understanding the overall health risk.

Methods: A cross-sectional study was conducted among 2,306 school children in Guangzhou and Shenzhen. Questionnaire data on respiratory symptoms and diseases were collected along with sociodemographic and residential environmental information. A subset of children (N=987) were measured for their lung function. A random forest algorithm was applied to screen the top-ranked indoor environmental exposure variables and to form a composite index for cumulative risk of indoor pollution (CRIP). Logistic regressions were conducted to analyze the independent effect of single indoor environmental risk factors and the combined effect of CRIP on children's respiratory health. Multiple linear regressions were used to examine the independent and combined effects of indoor environmental exposure on lung function.

Results: We found that home dampness and molds as well as environmental tobacco smoke (ETS) were significantly and independently associated with increased prevalence of children's respiratory symptoms and diseases and with reduced lung function. A higher CRIP level was significantly associated with increased risk of cough with cold (OR =1.37, 95% CI: 1.05-1.79) and wheeze (OR =2.71, 95% CI: 1.16-6.34). A higher CRIP level was also associated with reduced lung function measured as FVC, FEV₁, PEF, FEF_25%, FEF_25-75% and VC.

Conclusions: In children living in the subtropical region of the Pearl River Delta, home dampness and the presence of mold as well as ETS were individual risk factors for children's respiratory health. The composite CRIP index was associated with respiratory symptoms and lung function, suggesting the utility of this index for predicting the combined effects of multiple risk factors.

Keywords: Indoor environment; children; cumulative risk; lung function; respiratory diseases and respiratory symptoms.