Introduction

Respiratory infection and wheeze are a common cause of morbidity in early childhood. We studied the association between environmental factors and the risk of respiratory infections and symptoms in young children.

Methods

2312 Pregnant women were recruited to the GO-CHILD multi-centre birth cohort study from England and Scotland. Information on exposure to environmental factors, respiratory infections, symptoms, medication prescription and healthcare utilisation was obtained by follow-up questionnaires at 12 and 24 months after birth.

Results

Follow-up was obtained in 1344 children. Breastfeeding beyond six months was associated with a reduced risk of bronchiolitis (RR 0.62, 95%CI 0.44-0.87; p=0.006) and otitis media (RR 0.58, 95%CI 0.43-0.78; p<0.001). Daycare was associated with an increased risk of pneumonia (RR 2.16, 95%CI 1.02-4.52; p=0.042) and emergency department attendance for wheeze (RR 1.73, 95%CI 1.16-2.60; p=0.008). Visible damp was associated with an increased risk of reliever inhaler (RR 2.01, 95%CI 1.21-2.79; p=0.018) and inhaled corticosteroid prescription (RR 2.22, 95%CI 1.04-4.74; p=0.038). Dense traffic was associated with an increased risk of bronchiolitis (RR 1.41, 95%CI 1.00-1.99; p=0.048). Environmental tobacco smoke exposure was associated with an increased risk of wheeze (RR 1.36, 95%CI 1.11-1.67; p=0.009) and dry cough (RR 1.61, 95%CI 1.05-2.45; p=0.003).

Conclusion

Potentially modifiable environmental factors contribute to the risk of respiratory infections and symptoms in early childhood. The study informs on the benefits of breastfeeding and avoiding exposure to damp, vehicle emissions and secondhand smoke to mitigate these conditions.