Effects of parental smoking and indoor tobacco smoke exposure on respiratory outcomes in children

Yang Zhuge,Jan Sundell,Yinping Zhang,Hua Qian,Yuexia Sun,Xu Yang,Qihong Deng,Chen Huang,Zhuohui Zhao,Xiaohong Zheng,Xin Zhang,Baizhan Li

doi:10.1038/s41598-020-60700-4

Abstract

The extensive literature has reported adverse effects on environmental tobacco smoke (ETS) on children’s health. We aim to analyze associations of ETS with dry night cough, croup, pneumonia, and frequent common cold and to disentangle the effects of prenatal, infancy and childhood exposure by multilevel logistic regression. A cross-sectional study was conducted among 41,176 children aged 3–8 years in 8 major cities of China during 2010–2011, and obtained demographic information, smoke exposure information, and respiratory outcomes. Parents’ smoking habit and indoor tobacco smoke odor were considered as two indicators of ETS. The prevalences of respiratory outcomes were 6.0% for croup, 9.5% for frequency common cold, 17.1% for dry night cough and 32.3% for pneumonia respectively in the study. The associations between respiratory outcomes and parental smoking were not obvious, while indoor tobacco smoke odor was clearly and strongly associated with most respiratory outcomes, with adjusted odds ratios ranging from 1.06 to 1.95. Both infancy and childhood exposure to tobacco smoke odor were independent risk factors, but infancy exposure had a higher risk. The results explore that ETS increased the risk of respiratory outcomes in children, highlighting the need for raising awareness about the detrimental effects of tobacco smoke exposure.

Highlights

The extensive literature has reported adverse effects on environmental tobacco smoke (ETS) on children’s health
The study was restricted to 3–8 years old children because infancy and childhood exposure was difficult to distinguish for 1–2 years children and their sample sizes were relatively small
The incidence of common cold more than 6 times in recent 12 months was reported by 9.5%, while 17.1% reported having had dry night cough for more than two weeks and 14.3% of children had at least one respiratory symptom

Summary

Introduction

The extensive literature has reported adverse effects on environmental tobacco smoke (ETS) on children’s health. The associations between respiratory outcomes and parental smoking were not obvious, while indoor tobacco smoke odor was clearly and strongly associated with most respiratory outcomes, with adjusted odds ratios ranging from 1.06 to 1.95 Both infancy and childhood exposure to tobacco smoke odor were independent risk factors, but infancy exposure had a higher risk. Several studies focused on the independent effect of prenatal, postnatal and childhood exposure to tobacco smoke on children’s respiratory outcomes[1,16,17,18], yielding inconsistent findings. The main aim of the present study is to assess children’s exposure to tobacco smoke in utero, in the first year of life and childhood as risk factors for respiratory outcomes (including pneumonia, common cold, croup, and dry night cough). Our hypothesis is that earlier exposure to tobacco smoke exerts greater effects and that tobacco smoke exposure in any individual period is an independent risk factor for investigated respiratory outcomes

Objectives

Methods

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Discussion

Conclusion