Chronic respiratory morbidity and wheeze after preterm birth: a narrative review.

Preterm birth, defined as birth before 37 weeks of gestation, affects approximately 10% of pregnancies worldwide. Premature birth disrupts normal lung development with those born at earlier gestations most affected. Individuals born preterm are at increased risk of lifelong respiratory morbidity, including recurrent wheeze. As a consequence, affected individuals are often given an incorrect diagnosis of asthma. Asthma is considered a clinical description and is defined as a clinical syndrome characterised by wheeze, breathlessness, and chest tightness, sometimes accompanied by excess cough. This narrative review reports wheeze following preterm birth, considers prematurity-associated lung disease as an alternative diagnosis to asthma and discusses early life exposures as modifiable factors. Furthermore, whether prediction of those at highest risk is possible and what is the optimum management and follow up for affected individuals is discussed. Preterm birth is associated with an approximately double the risk of wheezing in childhood and is particularly common in those born extremely prematurely. While type two (T2) asthma is the predominant asthma phenotype in the general paediatric population, non-T2 mechanisms may be more relevant in those born preterm and hence why they are often unresponsive to standard asthma regimens. Potentially modifiable risk factors are antenatal corticosteroids,