Research in context
Evidence before this study
We did an informal search of the literature, including studies known to the authors, prior to this study. Early life factors, such as weight at birth, are associated with low lung function and chronic obstructive pulmonary disease (COPD) in late adulthood. Lung function development reaches a plateau in early adult life, and low lung function in young adults is associated with early mortality from all causes. Failure to attain maximal lung function at its plateau is associated with COPD in later life, even when the physiological rate of decline of lung function is maintained. This result strengthens the evidence that early life influences might be crucial for normal lung function in childhood and COPD pathogenesis.
Added value of this study
Using data from population-based, birth cohort studies, we demonstrated four discrete trajectories of FEV1 development from early childhood to young adulthood. Persistently low FEV1 was associated with wheezing and asthma through childhood and tobacco smoke exposure and was predicted by severe recurrent wheezing and allergic sensitisation by age 3 years. We were able to determine from a third independent cohort that most infants with low infant lung function trajectory during the first year after birth transitioned to normal or above average FEV1 trajectories.
Implications of all the available evidence
A persistently low trajectory of FEV1 development can be identified during childhood and is associated with potentially modifiable influences in early childhood. This trajectory was replicated in a companion study that followed FEV1 growth from childhood to late adulthood. Although perinatal factors are associated with low lung function during childhood and with later COPD, most infants with low lung function trajectories during the first year appeared to recover to average or above average FEV1 growth in later childhood. Interventions to maximise lung growth in early childhood might modify the risk of COPD in older age.