Educational intervention decreases exhaled nitric oxide in farmers with occupational asthma.

Allergic occupational asthma is frequent in farming populations. As educational interventions can improve disease management, the short-term effect of an educational intervention in asthmatic farmers was evaluated on the basis of spirometric indices and exhaled nitric oxide fraction (F(eNO)). Farmers with occupational asthma (n = 81), mostly sensitised against cow dander and storage mites, participated in a 1-day educational programme. Outcome measures were assessed at baseline and after 4-6 weeks, using F(eNO), lung function and a questionnaire. Results were compared with those of a control group without intervention (n = 24). In the educational group, the proportion of subjects reporting work-related symptoms was reduced after the intervention. The F(eNO) decreased from a geometric mean of 28.2 to 25.7 ppb, and, in subjects with an elevated (>35 ppb) baseline F(eNO) (n = 32), from 59.7 to 49.2 ppb. The corresponding changes in the control group were 25.6 versus 27.7 ppb and 49.5 versus 48.1 ppb. Spirometric results were unaltered in the two groups. Thus exhaled nitric oxide fraction, a marker of allergic airway inflammation, indicated a beneficial effect of a short-term educational intervention in farmers with occupational asthma. This suggests a potential for exhaled nitric oxide fraction in assessing the efficacy of preventive measures within a short time with higher sensitivity than spirometry.