Climate change, environmental exposures, and pediatric asthma exacerbations: air pollution, temperature, and relative...

The prevalence of pediatric asthma exacerbations (AEs) has risen alongside climate change, yet how climate change modifies these exposures to raise pediatric AEs remains unclear. This review synthesizes epidemiological and mechanistic evidence on the contribution of air pollution, temperature, and relative humidity (RH) to pediatric AEs under climate change, drawing on a narrative search of PubMed and Web of Science (2000-2025) prioritizing systematic reviews, epidemiological studies, and climate-attribution/modeling studies. Climate change intensifies environmental drivers of AEs, to which children's higher ventilation and reactive airways heighten susceptibility. Air pollutants trigger oxidative stress, epithelial injury, and type 2 inflammation, while rising temperatures and extreme weather increase oxidative stress, C-fiber activation, and systemic inflammation. Climate-driven shifts in RH cause airway dehydration at low humidity and impaired mucus clearance at high humidity. Lengthening pollen seasons, transitional-weather viral circulation, and more frequent wildfires, hurricanes, floods, and dust storms further increase exacerbation risk. Climate-driven environmental changes contribute to pediatric AEs, though attribution is quantified for only selected exposures. Prevention strategies, including heat- and air-quality warning systems, environmental adaptation, and equity-focused targeting of high-risk populations, are needed. IMPACT: Climate change amplifies environmental triggers of pediatric asthma exacerbations, a burden concentrated among disadvantaged children by socioeconomic and structural disparities. Children's physiological vulnerability heightens their sensitivity to these triggers. Closing pediatric-specific attribution gaps and integrating climate-adaptation strategies into asthma care could reduce this burden.