Infant lung function and wheeze in later childhood in the Southampton Women’s Survey

Abstract

To the Editor: We were interested to read the study by van der Gugten et al . [1] reporting associations between increased neonatal respiratory resistance and wheezing illnesses during infancy, and between reduced neonatal respiratory compliance and wheezing illnesses during the first 5 years of life and late-onset and persistent wheeze phenotypes. Reduced respiratory compliance was also associated with asthma, defined both according to primary care consultations and prescriptions or referral for wheezing illnesses, and according to patient-reported symptoms and lung function at the age of 5 years. The authors proposed that compliance and resistance might reflect different lung characteristics that are associated with symptoms in different age periods. Our data from normal-term infants in the Southampton Women’s Survey birth cohort provide further evidence that impaired physiological measurements soon after birth are associated with specific wheeze phenotypes. We previously reported an association between lower maximal flow at functional residual capacity ( V ′maxFRC) in early infancy and later transient wheeze [2]. The paper by van der Gugten et al . [1] has led us to analyse our data further with regards to compliance of the respiratory system ( C rs) and we have found that lower C rs is associated with asthma in our cohort too. Using the raised volume thoracoabdominal compression technique, we also measured forced expiratory volume in 0.4 s (FEV0.4); lower FEV …