BACKGROUND: Although the detrimental effects of environmental tobacco smoke (ETS) exposure and the beneficial role of physical activity (PA) on sleep health are well recognized, their combined influence on sleep-disordered breathing (SDB) in children remains unclear. This study investigates whether PA can mitigate the adverse effects of ETS on SDB in Chinese school-aged children.
METHODS: This cross-sectional study was conducted in the Yangtze River Delta Region of China. Data were collected through parent-reported questionnaires, covering information on children's demographics, ETS exposure, PA levels and types, as well as the occurrence of SDB. The study compared PA levels between children exposed and unexposed to ETS and examined associations with doctor-diagnosed sleep apnea and weekly snoring.
RESULTS: A total of 275 children (mean age: 9.6±2.7 years; 56.7% boys) participated. Among them, 31.6% were exposed to ETS at home daily. While most children (95.6%) engaged in daily outdoor play, only 26.5% met the WHO’s recommendation of 60 minutes of moderate-to-vigorous physical activity (MVPA) per day. Sleep apnea was reported in 6.9% of children, and weekly snoring in 32.0%. ETS exposure was significantly associated with an increased risk of SDB (p<0.001). However, regular outdoor activity reduced the likelihood of sleep apnea (p=0.02) and weekly snoring (p=0.01), with higher PA levels linked to lower risks. Logistic regression analysis also revealed a significant interaction between ETS and PA in relation to snoring prevalence (p=0.03).
CONCLUSIONS: Engaging in regular physical activity may help counteract some of the harmful effects of ETS on sleep and respiratory health in children. Identifying the optimal intensity and type of physical activity is essential to maximize its protective benefits.