Association of asthma with extra-respiratory symptoms in schoolchildren: two cross-sectional studies 6 years apart

Epidemiological information on symptoms affecting extra-respiratory organs and apparatuses in asthmatic children is scarce. The aim of this study therefore was to evaluate, at a population level, if and what extra-respiratory symptoms are associated with asthma. Two questionnaire-based, cross-sectional surveys were carried out on 1,262 students (651 males; mean age 9.57 years, age-range 6-14 years) in 1992 and on 1,210 students (639 males; mean age 9.02 years, age-range 6-14 years) in 1998, from two elementary and two junior high schools in Rome, Italy. Questionnaires included queries about asthma and its risk factors and extra-respiratory symptoms (headache, restlessness, sleep disturbance…