Atopy, asthma symptoms and eosinophilic airway inflammation in British woodworkers

Despite reducing exposures to wood dust, woodworkers remain at increased risk of asthma. There have been no recent studies of wood dust exposure, respiratory symptoms or asthma in British woodworkers. This cross-sectional study examined factors associated with asthma in British woodworkers across exposure groups.

Participants answered a reporter-delivered work and respiratory questionnaire, and underwent fractional exhaled nitric oxide (FE_NO), spirometry and specific IgE measurements. Wood dust exposure was assigned through a job-exposure matrix. Multiple regression evaluated associations between asthma and factors including exposure, atopy and current asthma symptoms (CAS).

A total of 269 woodworkers participated. Median wood dust exposure was 2.00 mg/m³ (IQR 1.14 mg/m³). CAS, work-related respiratory symptoms (WRRS) and eosinophilic airway inflammation (FE_NO>40 ppb) were common, present in 46%, 11% and 19% of the cohort, respectively. Atopic woodworkers were more likely to have nasal symptoms (OR 2.13, 95% CI 1.18 to 3.85, p<0.05), WRRS (OR 2.78, 95% CI 1.11 to 6.92, p<0.05), asthma (OR 3.40, 95% CI 1.49 to 7.81, p<0.01) and FE_NO>40 ppb (OR 2.00, 95% CI 1.03 to 3.88, p<0.05). No effect was seen for airflow obstruction. Symptomatic workers were more likely to have WRRS and asthma (OR 4.29, 95% CI 2.12 to 8.69, p<0.001) but not FE_NO>40 ppb or airflow obstruction. A dose-response effect with wood dust exposure was not seen.

Asthma symptoms were prevalent among British woodworkers, even at low exposure levels. Atopy was associated with asthma, particularly among symptomatic woodworkers. Further studies should phenotype woodworkers at risk of asthma and inform approaches to reduce risk.