The objective of this study was to examine the associations of childhood wheezing phenotypes with asthma, lung function and exhaled nitric oxide fraction (FeNO) in adolescence.In a population-based, prospective cohort study of 6841 children, we used latent class analysis to identify wheezing phenotypes during the first 7 years of life. Physician-diagnosed asthma, spirometry and FeNO were assessed at 14-15 years.Compared with never/infrequent wheeze, intermediate-onset and persistent wheeze were consistently strongest associated with higher risk of asthma (risk ratio (95% CI) 10.9 (8.97-13.16) and 9.13 (7.74-10.77), respectively), lower forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) ratio (mean difference in standard deviation units (SDU) (95% CI) -0.34 (-0.54- -0.14) and -0.50 (-0.62- -0.38), respectively), lower forced expiratory flow at 25-75% of FVC (FEF25-75%) (mean difference in SDU (95% CI) -0.30 (-0.49- -0.10) and -0.42 (-0.54- -0.30), respectively) and increased FEV1 bronchodilator reversibility (mean difference in SDU (95% CI) 0.12 (0.02-0.22) and 0.13 (0.06-0.19), respectively). Prolonged early and persistent wheeze were associated with a decline in FEV1/FVC ratio and FEF25-75% between 8-9 and 14-15 years. Intermediate-onset, late-onset and persistent wheeze were associated with higher FeNO ratios (ratio of geometric means (95% CI) 1.90 (1.59-2.29), 1.57 (1.39-1.77) and 1.37 (1.22-1.53), respectively, compared with never/infrequent wheeze).Early-onset wheezing phenotypes persisting after 18 months of age show the strongest associations with asthma, lower lung function, even worsening from mid-childhood, and higher FeNO levels in adolescence.
Copyright ©ERS 2016.