Engagement in Particulate Matter Exposure Reduction Behaviors Across Diverse Clinical Cohorts

Background and Objectives: We aimed to evaluate differences in PM exposure reduction behaviors among older adults and patients with chronic respiratory diseases, atrial fibrillation, and stroke and to identify associated determinants. Materials and Methods: This multicenter cross-sectional study included 717 participants from five cohorts: older adults (n = 255), chronic obstructive pulmonary disease (COPD, n = 145), asthma (n = 100), atrial fibrillation (n = 117), and stroke (n = 100). PM exposure reduction behaviors were assessed using a standardized 18-item questionnaire (total score range: 0-126) covering indoor, outdoor, and other behaviors (health-seeking actions, such as checking air quality and using purifiers). Results: In multivariable linear regression models, COPD (β = 11.09), asthma (β = 15.54), and atrial fibrillation (β = 14.29) were associated with significantly higher total behavior scores compared with the older adult cohort (adjusted mean 69.0), corresponding to an approximately 20% relative increase in the asthma cohort. The stroke cohort did not differ significantly from the primary cohort. Domain-specific analyses showed that indoor and other behavioral scores were consistently higher across all disease cohorts, whereas outdoor scores were significantly elevated only for asthma and atrial fibrillation. In a fully adjusted model that included all covariates simultaneously, the stroke cohort demonstrated a modest increase in the total score (β = 8.79). Increased age and higher educational attainment were independently associated with greater behavioral engagement. Conclusions: PM exposure reduction behavior scores differed across the clinical cohorts, and sociodemographic factors were independently associated with behavioral engagement. These findings support personalized disease-specific counseling and inform future digital health interventions for vulnerable populations.