The Early-Life Risk Factors of Childhood Wheezing: Results from the NHANES During 2005-2012

Abstract Objectives: Wheezing is the most common cause of hospitalization during childhood. The aim of the present study was to identify early-life risk factors predisposing to childhood wheezing using directed acyclic graph (DAG) analysis.Methods: In this study, we used the National Health and Nutrition Examination Survey (NHANES) data to identify the risk factors associated with wheezing in children aged 1-15 years old in the United States. The data was related to four 2-year cycles from 2005 to 2012. All the adjusted analyses were based on the directed acyclic graph(DAG). The applied logistic regression was performed by survey analysis to adjust the weights of samples.Results: From 13203 children, 87.2% (n = 11 519) had not experienced wheezing during the past year, and 12.8% (n=1684) experienced wheezing during the same time. The mean ages (SD) were 6.6 (4.4) and 7.6 (4.4) years old in wheezing and healthy children respectively. Boys comprised a significantly higher ratio in wheezing compared with healthy children (P = 0.001). Mother smoking during pregnancy (MSDP) was a significant risk factor for childhood wheezing (OR= 1.42, 95% CI: 1.15-1.74, P = 0.001). All ethnicities other than the Mexican-American were established as significant risk factors for childhood wheezing. On the other hand, childhood wheezing was insignificantly associated with Socio-economic status, birth weight, maternal age at pregnancy, and exposure to smoke at home.Conclusion: After adjusting for established confounders, history of MSDP, as well as ethnicity delivered important risk factors for childhood wheezing in a large population of the US.