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Published on: November 4, 2010
Prevalence of bronchial asthma among schoolchildren in a Swedish district
L Bråbäck1, L Kälvesten, G Sundström
1Department of Paediatrics and Clinical Physiology, Sundsvall Hospital, Sweden.
Abstract:
The prevalence of asthma among 10,527 children aged 7-16 years was investigated in 1985. Children were assigned to the asthma group when replies to a questionnaire stated that at least two of four stipulated symptoms had been experienced in the preceding year. A validation study, comprising exploration of medical history, pulmonary auscultation and physiological tests (spirometry and methacholine inhalation challenge) was performed in 73 children. The overall prevalence of asthma was 4%. The most common symptom-inducing factors were physical exertion, upper respiratory tract infection, contact with animals and tobacco smoke. The methacholine test had limited value as a diagnostic aid, being positive in only 25% of children with a clear history of asthma.
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