Chronic respiratory symptoms and lung function parameters in large-scale wood factory workers in Addis Ababa, Ethiopia: a comparative cross-sectional study

Background Occupational wood dust causes chronic respiratory health problems as well as a decline in lung function. However, data on the prevalence of chronic respiratory symptoms and lung function parameters among large-scale wood factories workers in Ethiopia producing furniture are limited. The objective of this study was to determine the prevalence of chronic respiratory symptoms, lung function measures, and associated factors among large-scale wood industry workers in Addis Ababa, Ethiopia. Methods An institution-based cross-sectional study was conducted among 232 wood workers and 232 controls. Participants for the study were selected using stratified and systematic sampling from soft drink and wood factories. The chronic respiratory symptoms were assessed using a modified American Thoracic Society (ATS) questionnaire, and lung function tests were performed using an Easy on PC spirometer in accordance with the ATS standards for spirometry. The data were imported into Epi-data version 4.4.2 and analyzed with SPSS version 23. Poisson regression, Multivariate linear regression and multivariable logistic regression analysis were used. Results The prevalence ratio of overall chronic respiratory symptoms was significantly higher among woodworkers (65.7%) compared to controls (23.3%) in this study (PR = 2.17, 95% CI: 1.51–3.12). Current chronic respiratory symptoms were associated with gender, and previous chronic respiratory disease. Woodworkers had significantly lower Forced vital capacity (FVC) and Forced expiratory volume in the first second (FEV1) when compared to controls. Conclusion Woodworkers had a higher prevalence of chronic respiratory symptoms and lower lung function measures, which lowered lung capacity when compared to controls. To reduce workers' exposure to wood dust, engineering control methods should be implemented.