Pulmonary function development in children with past history of asthma.
STUDY OBJECTIVE--The aim was to examine whether or not the children with a past history of asthma but free from asthmatic attacks for several years show a different growth pattern in pulmonary function from control children. DESIGN--A community based cohort was surveyed three times during a four year follow up period. SETTING--Kashima district in Ibaraki prefecture, Japan. PARTICIPANTS--In 1980, 441 primary school children between 113 and 124 months of age were enrolled as an initial cohort; 325 of these provided reliable results in each of the three surveys. MAIN RESULTS--A level and a slope of FVC, FEV1, Vmax50, and Vmax25 were calculated for each child, based on a general linear model analysis. Past histories of each child were determined from a standardised questionnaire. The children with a history of doctor diagnosed asthma showed a lower Vmax50 level (p < 0.005) and a lower level and slope of Vmax25 (p < 0.005, p < 0.01) than control children, even when only those who did not suffer from wheezing attacks during the follow up period were considered. CONCLUSIONS--Indices of peripheral airways function in children with an asthmatic history were reduced even if they had been in remission for several years. The difference in pulmonary function in comparison to control children might become greater at the time of the adolescent growth spurt.