Factors associated to airway obstruction development in asbestos exposed workers in Navarra

Asbestos exposure, as well as other inorganic dusts, are capable of developing lung function impairment, including airflow obstruction (AO). We have been performing medical check-ups to asbestos exposed workers since year 2000. Such visits include a spirometry. AO prevalence (PRV) and incidence (INC) were calculated. Using univariate Cox regression analysis, we aimed to assess the factors associated to AO development, stratifying by smoking status. Workers with asbestos related diseases were excluded from analysis (n=58). Up until 02.2016, 626 workers had baseline spirometric data. Baseline characteristics are shown in Table 1. The sample was mainly male, ever smokers (74%), with normal lung function. Overall AO PRV was 14% (11% and 15% in never and ever smokers, respectively). Overall AO INC was 18% along a mean follow-up period of 147 mo (14% and 20% in never and ever smokers, respectively) (Table 2). In never smokers, age and exposure time were significant risk factors for AO development (HR 1.08, 95%CI 1.02-1.14; and HR 1.08, 95%CI 1.03-1.14, respectively). In smokers, age, smoking intensity (pack years), impaired baseline FEV1, exposure time and latency period were significant risk factors (Table 3). In our cohort of asbestos exposed workers, airflow obstruction PRV and INC in never smokers, was slightly lower than that observed in smokers. An 8% increased risk per year exposed was observed in never smokers.