Final answer:
Childhood asthma is more common in affluent nations and more serious in poorer nations.
Step-by-step explanation:
Asthma is a chronic inflammatory disease of the airways in the lungs, in which the airways periodically become inflamed. This causes swelling and narrowing of the airways, often with excessive mucus production, leading to difficulty breathing and other symptoms. Asthma attacks are triggered by allergens, air pollution, or other factors.
A study by Lai et al (2009) found that childhood asthma was more common in affluent nations and more serious in poorer nations. This could be attributed to several factors, such as differences in access to healthcare, exposure to environmental triggers, and living conditions. For example, affluent nations may have better healthcare systems and resources to manage and treat asthma, while poorer nations may struggle to provide adequate healthcare for asthma management.