Visible damp in a child's bedroom is associated with increased respiratory morbidity in early life: a multicentre cohort study.

Objective: Household damp exposure is an important public health issue. We aimed to assess the impact of the location of household damp on respiratory outcomes during early life.

Methods: Household damp exposure was ascertained in children recruited to the GO-CHILD multicentre birth cohort study. The frequency of respiratory symptoms, infections, healthcare utilisation and medication prescription for wheezing were collected by postal questionnaires at 12 and 24 months. Log binomial and ordered logistic regression models were fitted to the data.

Results: Follow-up was obtained in 1344 children between August 2010 and January 2016. Visible damp was present in a quarter of households (25.3%) with 1 in 12 children's bedrooms affected (8.3%). Damp in the bathroom, kitchen or living room was not associated with any respiratory or infection-related outcomes. Damp in the child's bedroom was associated with an increased risk of dry cough (8.7% vs 5.7%) (adjusted relative risk 1.56, 95% CI 1.07 to 2.27; p=0.021) and odds of primary care attendance for cough and wheeze (7.6% vs 4.4%) (adjusted OR 1.37, 95% CI 1.07 to 1.76; p=0.009). There were also increased risk of inhaled corticosteroid (13.3% vs 5.9%) (adjusted RR 2.22, 95% CI 1.04 to 4.74; p=0.038) and reliever inhaler (8.3% vs 5.8%) (adjusted RR 2.01, 95% CI 1.21 to 2.79; p=0.018) prescription.

Conclusion: Damp in the child's bedroom was associated with increased respiratory morbidity. In children presenting with recurrent respiratory symptoms, clinicians should enquire about both the existence and location of damp, the presence of which can help prioritise those families requiring urgent household damp assessment and remediation works.