Climate change. Asthma. Allergies. What can be done in practice?. Analysis of climate change adaptation measures for childhood asthma: a systematic review of epidemiological evidence.

The increase in temperature, which in turn determines extreme weather events such as heat waves, fires, storms, droughts, is one of the most important indicators of global climate change. This increase in temperature has upset all the ecosystems of the world, causing damage to many aspects of the social fabric, the environment and human health.

It is now well established the causal link between exacerbation of asthma, rhinitis, atopic dermatitis and air quality, which is likely to worsen with increasing temperatures, which in turn will lead to an increase in the concentration of nitrogen dioxide (NO2) from fossil fuel vehicles. 

Despite this evidence, countries around the world continue to make little progress to slow the pace of global climate change. 

Although GCC is an important risk to everyone’s human health, there are some categories of individuals who are most at risk of adverse events, including the elderly, children, pregnant women and people with chronic diseases. 

It is no coincidence that asthma and allergies are among the most common childhood diseases, with a significant impact primarily on the individual and then on his family and finally on the community. 

Children are more vulnerable for many reasons. In the 0-4 age group, these have a risk of exposure to toxic agents per higher body unit, an immature immune system, immature organs, developing and finally a reduced ability to thermoregulate. 

Between 5 and 9 years old, the group with the highest prevalence of asthma, it appears that the most susceptibility factor is the variation in daytime temperature and the increased susceptibility of this category of children to this variation and finally to the 10-14 age group, Age group in which the outdoor game is greater, it seems that it is precisely the exposure to the cold to be the main trigger for the appearance of asthma crisis. 

To prove this some studies of Wales and the United Kingdom, where certainly the climates are very different from ours, have assessed the health benefits of taking appropriate measures for ventilation and domestic heating and have demonstrated that reducing the temperature changes in homes (with adjustment of domestic heating) associated with adequate ventilation of the rooms (or open the windows in the hottest hours of the day when there was no traffic) meant that children went from having a "severe asthma" to a "moderate asthma", without other interventions.

However, it is clear that continued exposure to air pollution can only be an additional burden on the respiratory health of the child, whose lungs are still immature until adulthood. For allergy sufferers, however, the increase in temperatures will lead to more and more early and longer blooms with the risk of worsening allergies and exacerbation of asthmatic crises.

A systematic review of the literature has been carried out to investigate what measures are actually useful and what can be put in place to safeguard the health of children.

Several measures have been proposed to try to reduce the impact of GCC on the individual but at the moment nothing, apart from the control of temperature in the domestic environment in regions with more rigid climates, has shown to bring concrete and conclusive results.

Since both the GCC and the direct consequences it is having on human health are clearly increasing, it is imperative in the short term to explore what measures can be used to minimise climate impacts on allergies, on asthma and the quality of breathing especially in children. 

New studies and new reflections on the subject must therefore be on the agenda. 

 Bibliografia

Yabin Hu, Jian Cheng, Shijian Liu, Jianguo Tan, Chonghuai Yan, Guangjun Yu, Yong Yin, Shilu Tong Evaluation of climate change adaptation measures for childhood asthma: A systematic review of epidemiological evidence  Sci Total EnvironPMID: 35644404 DOI: 10.1016/j.scitotenv.2022.156291

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