Background: The effect of childhood asthma on lung growth is unclear.
Objective: To show the effect of mild to moderate childhood asthma on lung growth.
Methods: A total of 1041 children with mild to moderate asthma from the Childhood Asthma Management Program (CAMP) were compared with 5415 children without asthma from the Harvard Six Cities Study (H6CS). Sex-age-specific comparisons of lung growth in CAMP with the H6CS were made by using repeated-measures multiple linear regression models. Sex-age-specific percentages of children with asthma with abnormal (<5th percentile of H6CS) pulmonary function values were calculated.
Results: In both boys and girls, the ratio of FEV(1) to forced vital capacity (FVC) was significantly lower for children with than without asthma (P < .001), with corresponding increases for children with asthma in FVC (P < .001). FEV(1) was lower for boys with asthma than for boys without asthma (P < .001), but not for girls (P = .14). Percentages of CAMP children with abnormal FEV(1)/FVC ratios increased with age for both sexes (P < .001). The patterns of lung growth for children with asthma compared with children without asthma did not differ among children treated for 4.3 years with budesonide or nedocromil and placebo during the CAMP trial.
Conclusion: Mild to moderate asthma results in a pattern of airway obstruction that increases in magnitude from age 5 to 18 years.
Clinical implications: Periodic spirometry is needed to monitor children with asthma for signs of increasing airway obstruction with appropriate intervention following national guidelines.