Abstract
We hypothesize that green areas within cities affect the respiratory symptoms of individuals with asthma, but this effect may not be the same for all age groups, because the immunopathology of asthma in children-adolescents is different from the immunopathology of asthma in adults. The objective of this study is to evaluate whether there is an association between the percentage of green area close to the residence and asthma outcomes, stratified by age group. We included individuals with asthma over the age of ten years. Two independent trained researchers measured, in satellite images, the extent of green area around the residence. The primary outcome of the study was the severity of respiratory symptoms measured by the Asthma Control Test. The secondary outcome was the presence of airway obstruction in the spirometry test carried out on the day of the study visit. Binary logistic regression analyzes evaluated whether the percentage of green area close to the residence was associated with asthma outcomes. In children-adolescents, greater density of green area was associated with a greater frequency of uncontrolled asthma symptoms. In adults, greater density of green area was associated with a lower frequency of uncontrolled asthma symptoms and a lower frequency of airway obstruction. We conclude that the extent of green areas close to the residence is associated with asthma morbidity. The expansion of green areas within cities should favor species that do not disseminate pollen with allergenic potential, especially in regions close to schools and daycare centers.