D13-01 Mucus Plugs and Lung Function: Findings From Two Population-based Cohorts

Abstract Rationale Airway-occluding mucus plugs (MPs) are linked to reduced lung function in individuals with chronic lung diseases, but their impact has not been systematically evaluated in the general population. Therefore, we aimed to examine whether MPs are associated with impaired lung function in community-dwelling persons. Methods We analyzed data from adult participants in the Framingham Heart Study (FHS) Offspring Cohort and Coronary Artery Risk Development in Young Adults (CARDIA) study. Chest computed tomography (CT) scans were obtained in 2008-2011 (FHS) and 2010-2011 (CARDIA), and trained readers visually counted the number of lung segments with airway-occluding MPs (range: 0-18). Scores were categorized as 0 versus 1+ for this analysis. Spirometry was performed before and after CT scanning (FHS: Exams 8 2005-2008 and 9 2011-2014; CARDIA: Year 20 2005-2006 and Year 30 2015-2016). Linear mixed-effects models assessed associations between MPs and repeated lung function measures, including forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), and FEV1/FVC ratio. Models adjusted for age, sex, self-reported race, BMI, education, smoking status, pack-years, asthma, and study center (CARDIA). Analyses were performed using R 4.4.1. Results Of 1,114 FHS participants (mean age, 68.9 years; 57 % women) and 2,747 CARDIA participants (mean age, 45.3 years; 57.8% women), 332 (30%) and 382 (14%), respectively, had MPs. In adjusted models, compared with individuals without MPs, FHS participants with 1+ lung segments with MPs had lower FEV1 (represented as negative values) (-203.4 mL; 95% CI, -265.0, -141.8) and FEV1/FVC*100 ratio (-3.37%; 95% CI, -4.23%, -2.51%). In CARDIA, corresponding values were -129.1 mL (95% CI, -176.5, -81.7) for FEV1 and -3.3% (95% CI, -3.9%, -2.7%) for FEV1/FVC ratio. Over the follow-up, annual FEV1 decline did not differ by 1+ vs. 0 MP groups (FHS: -32.1 mL/year vs. -31.7 mL/year; p = 0.87; CARDIA: -29.7 mL/year vs. -29.5 mL/year; p = 0.95) nor did annual declines in FEV1/FVC ratio (FHS: -0.003% vs. -0.057% per year; p = 0.23; CARDIA: -0.21% per year vs. -0.17% per year; p = 0.13). Secondary analyses assessed the association between MPs and COPD development (FEV1/FVC 0.7) post-CT scan among participants without pre-CT scan COPD. Individuals with 1+ MP had higher odds of developing COPD post-CT scan (FHS: OR 1.79, 95% CI: 1.02, 3.14; CARDIA: OR 1.94, 95% CI: 1.30, 2.89). Conclusions In community-dwelling persons, MPs were associated with lower lung function and obstructive pathophysiology, but not with accelerated decline in FEV1. This abstract is funded by: US National Heart, Lung, and Blood Institute (R01-HL149861, R01-HL164824, R01-HL173017)