There are large variations globally in the prevalence of asthma in children.
Time trends have shown a mixed picture:
- increases in low prevalence centres
- plateau or even a decrease in high prevalence centres
Atopy has less influence on asthma in low and middle income countries. Breast feeding exerts a protective effect only on non-atopic asthma in non-affluent countries.
Recent perspectives on global epidemiology of asthma in childhood. Asher MI. Allergol Immunopathol (Madr). 2010 Jan 25. [Epub ahead of print]
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