The effects of temperature variation on obstructive pulmonary dysfunction and small airway dysfunction in asthmatic...

Childhood asthma is increasingly prevalent globally, leading to a significant disease burden with rising incidence and greater healthcare demands. However, previous research has primarily focused on the impact of temperature variation on hospital visits of childhood asthma, with limited evidence on the effects of lung function parameters. In this continuous eight-year study, we investigated the impact of temperature variation on obstructive pulmonary dysfunction and small airway dysfunction in asthmatic children during summer and winter in Jinan, China. The temperature variation was defined as temperature change between two neighboring days (TCN). Generalized linear models (GLM) were employed to explore associations between temperature variation and obstructive pulmonary ventilation dysfunction, small airway dysfunction and pulmonary function parameters. Results indicated a heightened risk of obstructive pulmonary dysfunction associated with temperature variation, with ORs of 1.103 (95% CI: 1.002, 1.212) for per 1 °C increase in TCN in summer and 1.109 (95% CI: 1.000, 1.221) for per 1 °C decrease in winter. Similar results were found for small airway dysfunctions, indicating a consistent pattern of risk associated with temperature variation. Additionally, TCN was associated with a statistically significant decline in several lung function parameters, including FEV₁/VCmax, FEV₁/FVC, MEF₂₅, MEF₅₀ and MMEF in winter. The subgroup analysis by gender revealed that the harmful effects of temperature variation were more pronounced in females during summer and in males during winter. In conclusion, this study found that temperature variation posed significant impacts on the lung function of asthmatic children, which highlighted the need for adaptation strategies to mitigate adverse effects of climate change on children's respiratory health, such as avoiding outdoor activities during significant temperature fluctuations.