Lifestyle practices that reduce seasonal PM(2.5) exposure and their impact on COPD.

Particulate matter (PM) is a major air pollutant that has led to global health concerns and can cause and exacerbate chronic obstructive pulmonary disease (COPD). We asked patients with COPD to complete a detailed questionnaire about their lifestyle practices to reduce PM(2.5) exposure and analyzed the relationship between ambient PM(2.5) concentrations and lifestyle practices. We prospectively enrolled 104 COPD patients from four hospitals in different areas of Korea. They completed detailed questionnaires twice (at enrollment and the end of the study) and Internet of Things-based sensors were installed in their homes to continuously measure PM(2.5) for 1 year. The relationship between PM(2.5) concentrations, lifestyle practices, and COPD exacerbations were analyzed in each season. The PM(2.5) concentration was higher outdoors than indoors in all seasons except summer, and the difference was largest in winter. The six lifestyle practices that significantly lowered the annual indoor PM(2.5) concentration compared with the outdoors. The higher the economic status and educational level of patients, the lower the indoor PM(2.5) concentration. Some lifestyle practices were associated with reduced small airway resistance, presented as R5-R20 determined by impulse oscillometry, and scores of the St. George's Respiratory Questionnaire. Some lifestyle practices are associated with reduced indoor PM(2.5) concentrations and can even affect clinical outcomes, including small airway resistance and quality of life of COPD patients.