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.

dx.doi.org/10.1183/13993003.00718-2015, hdl.handle.net/1765/83256
The European Respiratory Journal
This work was funded by the European Commission 7th Framework Programme; grant id fp7/229571 - Respiratory Science Promoted by International Research Exchanges (RESPIRE)
Department of Epidemiology

Duijts, L, Granell, R, Sterne, J.A.C, & Henderson, A.J. (2016). Childhood wheezing phenotypes influence asthma, lung function and exhaled nitric oxide fraction in adolescence. The European Respiratory Journal, 47(2), 510–519. doi:10.1183/13993003.00718-2015