Asthma and global climate change

Global climate change is expected to result in direct and indirect changes in factors that are associated with asthma exacerbation. These factors include the weather (e.g., thunderstorms, sudden temperature or pressure changes), outdoor air pollutants (e. g., ozone, sulfur oxides, nitrogen oxides), and outdoor aeroallergens. Global climate change will manifest as highly variable climate change between regions, prohibiting generalizations about future changes in weather variables. A more active hydrologic cycle may produce more frequent and severe thunderstorms and cooling episodes. Warmer temperatures are associated with higher ozone concentrations. Lastly, pervasive climate changes are likely to alter dominant vegetation in specific regions, with secondary changes in aeroallergen timing and intensity. Whether some or all of these changes will have an impact on overall asthma incidence is highly uncertain. Indoor allergens and infection-related shifts in T-helper responses, which appear to play significant roles in the pathogenesis of asthma, are less likely to be affected by global climate change.