Identification of Modifiable Risk Factors of Exacerbations Chronic Respiratory Diseases with Airways Obstruction, in Vietnam

Objectives: to determine modifiable risk factors of exacerbations in chronic respiratory diseases with airways obstruction (i.e., asthma and COPD) in southern Vietnam. Methods: an environmental and health-related behavioural questionnaire was submitted to patients with both chronic respiratory symptoms and airways obstruction. An exacerbation was defined as any acute worsening in clinical symptoms requiring a change in treatment, in a patient receiving prophylactic therapy. Results: 235 patients were evaluated, including 131 (56%) chronic obstructive pulmonary disease (COPD) and 104 (44%) asthmatics. There were 75% males and 69% smokers. Occupational exposure accounted for 66%, mainly among construction and industry workers. Smoking was associated with more severe airways obstruction. Respiratory exacerbations were reported in 56/235 patients (24%). The risk of exacerbation was increased in patients with a lower education level, exposure to occupational pollutants, cumulative smoking ≥ 20 pack year, housing space < 10 m(2), and poorly ventilated housing. Based on multivariate analysis, the risk of exacerbation remained significantly higher among patients with occupational exposure and low housing space per person. Conclusions: besides smoking cessation, more supportive policies, including improvement of occupational environment and housing design for better ventilation, are needed to prevent the severity of chronic respiratory diseases in Vietnam.