Acute inhalations in the workplace are associated with new-onset asthma in women

Abstract

Acute-onset irritant-induced asthma is a phenotype with onset promptly after a single, high-level exposure to irritants in subjects without pre-existing asthma. Our aim was to study new-onset adult asthma in relation to acute inhalations in a population-based study. We used longitudinal data of 3,141 ECRHS III participants from 24 study centres (52% women, aged 39-67 years) with no reported history of asthma or related symptoms in previous contacts. Details of acute inhalations (incident at home, work or elsewhere involving exposure to high levels of vapours, gases, dusts or fumes) during the last follow-up (mean 11.3 years) were reported. Associations between inhalations and new-onset asthma during follow-up were analysed using multivariable logistic mixed regression analyses adjusted for sex, age, follow-up time, smoking status and centre. 82 participants (2.6%) had developed asthma during follow-up (2.3 new cases per 1000 person-years). An acute inhalation during follow-up was reported by 188 participants (6.0%), and was associated with new-onset asthma (odds ratio (OR) 2.8; 95% confidence interval 1.4-5.5). This association was predominated by inhalations in the workplace (52% of all; OR 5.1 (2.3-11)) while inhalations elsewhere were not associated with asthma (OR 0.9; 0.2-3.8). The increased asthma risk of inhalations at work was much stronger (p for interaction 0.02) in women (OR 10; 4.0-26) than in men (OR 1.2; 0.2-9.4). Analyses using current asthma based on symptoms or medication showed consistent findings for inhalations at work; OR 8.8 (3.8-20) in women and 0.4 (0.1-3.0) in men (p for interaction 0.0002). We conclude that acute inhalations at work may induce asthma, particularly in women.