Dynamics of respiratory symptoms during infancy and associations with wheezing at school age
Date
2018Author
Usemann, JakobXu, Binbin
Delgado-Eckert, Edgar
Korten, Insa
Anagnostopoulou, Pinelopi
Gorlanova, Olga
Kuehni, Claudia
Röösli, Martin
Latzin, Philipp
Frey, Urs
ISSN
2312-0541Source
ERJ Open ResearchVolume
4Issue
4Google Scholar check
Metadata
Show full item recordAbstract
Children with frequent respiratory symptoms in infancy have an increased risk for later wheezing, but the association with symptom dynamics is unknown. We developed an observer-independent method to characterise symptom dynamics and tested their association with subsequent respiratory morbidity. In this birth-cohort of healthy neonates, we prospectively assessed weekly respiratory symptoms during infancy, resulting in a time series of 52 symptom scores. For each infant, we calculated the transition probability between two consecutive symptom scores. We used these transition probabilities to construct a Markov matrix, which characterised symptom dynamics quantitatively using an entropy parameter. Using this parameter, we determined phenotypes by hierarchical clustering. We then studied the association between phenotypes and wheezing at 6 years. In 322 children with complete data for symptom scores during infancy (16 864 observations), we identified three dynamic phenotypes. Compared to the low-risk phenotype, the high-risk phenotype, defined by the highest entropy parameter, was associated with an increased risk of wheezing (odds ratio (OR) 3.01, 95% CI 1.15–7.88) at 6 years. In this phenotype, infants were more often male (64%) and had been exposed to environmental tobacco smoke (31%). In addition, more infants had siblings (67%) and attended childcare (38%). We describe a novel method to objectively characterise dynamics of respiratory symptoms in infancy, which helps identify abnormal clinical susceptibility and recovery patterns of infant airways associated with persistent wheezing. Tweetable abstract @ERSpublications click to tweetUnsupervised analysis of symptom dynamics during infancy identifies subjects susceptible to persistent airway disease http://ow.ly/r9xz30lDpHB