Time trends in respiratory symptoms in childhood over a 24 year period.

摘要: Two cross sectional surveys, 24 years apart, using the same respiratory questionnaire, were carried out to examine changes in prevalence rates of cough, phlegm, and wheeze relate objective peak expiratory flow (PEFRs). The surveys done towns southern northern England South Wales schoolchildren aged 6.0-7.5 years; n = 1655 1966 2323 1990. Parents reported on winter cough phlegm (early morning or day/night) wheeze; PEFRs also measured. proportion children as wheezing most days nights increased from 3.9% 6.1% (95% confidence interval (CI) for increase -0.2 4.6), with a smaller those who had ever wheezed. day night time 21.1% 33.3% CI 3.8 20.6) 5.8% 10.0% 0.4 8.0). Smaller increases persistent (from 9.0% 12.4%) 2.4% 3.5%) observed, while showed little change. apparent subjects without history wheeze. Both absolute proportional symptom generally greater north than south. Similar social class trends seen each survey. mean difference PEFR between was 1990 1966, but this result could be influenced by receiving antiasthmatic treatment These wheeze, occurring over period during which outdoor air pollution levels have decreased substantially, deserve further investigation.