Abstract Introduction Bronchiectasis is a chronic respiratory disease that increases fatigue, disability, and impairs quality of life. However, the impact of fatigue on patients with bronchiectasis, even in short-term follow-up, has not been sufficiently examined. We explored the association between fatigue and clinical outcomes among patients with bronchiectasis. Methods Adult bronchiectasis patients enrolled in the US Bronchiectasis and Nontuberculous Mycobacteria Research Registry were retrospectively analyzed. Patients with at least one annual follow-up visit in the 3-5 years post baseline and with fatigue data at both baseline and follow-up were included. Patients were grouped as experiencing fatigue versus not experiencing fatigue in the 2-years prior to baseline as reported at their baseline visit. We explored the relationship between baseline fatigue with patient demographics, co-existing conditions, components of the modified bronchiectasis severity index at baseline and follow-up. Wilcoxon, chi-square, and Fisher’s exact tests were used to assess the differences in continuous variables and associations between categorical variables, respectively. Stepwise multivariable logistic regression models explored the relationship of baseline fatigue with exacerbations and hospitalizations at follow-up. Model selection predictors were evaluated based on clinical relevance or p < 0.05 in univariable analyses. Results 1265 adults with bronchiectasis met the inclusion criteria. 563(45%) reported experiencing fatigue and 702 (55%) did not. The median age (interquartile range) was 70(62-78) years and patients were predominantly female (n = 1042, 83%). At baseline, patients experiencing fatigue had a higher proportion of co-existing diagnoses such as gastroesophageal reflux disease, chronic obstructive pulmonary disease, and rheumatologic disease, compared to those without fatigue (all p < 0.05). Furthermore, patients with fatigue had a higher prevalence of pulmonary-related hospitalizations (p < 0.001) at baseline and follow-up. Pseudomonas aeruginosa colonization and elevated dyspnea (modified Medical Research Council [mMRC] grade≥1) were more prevalent among those experiencing baseline fatigue compared to those without (all, p < 0.05). History of prior exacerbations (Odds Ratio [OR]:1.67, 95% CI:1.17-2.41) and baseline Pseudomonas aeruginosa colonization (OR:1.22, 95% CI:1.01-1.47) were significantly associated with increased odds of exacerbations at follow-up. In multivariable stepwise logistic regression, there was an increased odds of at least 1-hospitalization at follow-up among males (OR:2.23, 95% CI 1.12-4.42), patients with decreased Body Mass Index (OR:0.93, 95% CI: 0.87-1.0), and among patients with elevated dyspnea (mMRC grade ≥1) at baseline (OR:2.22, 95% CI: 1.16-4.24),[Table 1]. Conclusions Fatigue in bronchiectasis patients is associated with a more severe disease and greater healthcare utilization, although it may not independently predict future exacerbations or hospitalizations when accounting for other factors. This abstract is funded by: Bronchiectasis and NTM Association
B45-19 Purulent Sputum as a Marker of Systemic Inflammation and Bacterial Growth in a Cross-Sectional Cohort of Non-CF Bronchiectasis
Abstract Background Sputum color is a visual marker of airway inflammation and disease activity in bronchiectasis, ranging from clear or light gray (mucoid) to yellow-green (purulent), the latter largely reflecting neutrophil myeloperoxidase release. This study evaluated associations between sputum color and common clinical markers of disease activity to determine which parameters differed most between color categories. Methods Forty spontaneous sputum samples were analyzed from 80 consecutive adults with non-cystic fibrosis bronchiectasis (median age 70 years [IQR 12]; 74% female) enrolled between January 2024 and April 2025 in an observational study. Sputum color was graded using the Murray Sputum Color Chart and classified as mucoid (color #1) or purulent (colors #2-4). Clinical parameters, including blood cell counts, C-reactive protein (CRP), fractional exhaled nitric oxide (FeNO), and results of bacterial and acid-fast bacillus cultures (induced or bronchoscopic), were obtained from medical records if available within one month of enrollment. Categorical variables were analyzed using chi-square or Fisher’s exact tests and continuous variables with the Mann-Whitney U test. A secondary analysis compared patients who could versus could not produce spontaneous sputum. Results Of 40 samples, 20 (50%) were purulent. Blood neutrophil counts (median 4.5 vs. 3.9 x109/L), neutrophil-to-lymphocyte ratios (2.5 vs. 2.6), and eosinophil counts (1.7 vs. 1.7 x109/L) did not differ significantly between groups (n = 26). FeNO was normal in all 10 patients with available data and was not analyzed further. CRP was higher among patients with purulent sputum (4.6 vs. <3 mg/L; n = 20; p = 0.044). Bacterial growth was more frequent in purulent than mucoid samples (73% vs. 31%; n = 31; p = 0.032). Isolates in the purulent group included Klebsiella, Pseudomonas, Staphylococcus, and Streptococcus (n = 2 each), and single isolates of Acetobacter, Acinetobacter, Chryseobacterium, Delftia, Enterobacter, Escherichia, and Moraxella. In the mucoid group, Pseudomonas, Staphylococcus (n = 2 each), and Stenotrophomonas (n = 1) were identified. Mycobacterial growth did not differ significantly (20% vs. 12.5%; n = 31; p = 0.65). Patients unable to produce spontaneous sputum had a higher rate of mycobacterial isolation on induced/bronchoscopic samples (43% vs. 16%; n = 54; p = 0.027), though other parameters were similar. Over 90% of measurements were obtained within three days of enrollment, and freezing did not appear to alter sputum color. Conclusions Even within a small cohort, purulent sputum was associated with higher CRP and greater bacterial growth, supporting sputum color as a rapid, inexpensive marker of disease activity in bronchiectasis. Further research should clarify whether sputum color primarily reflects bacterial colonization, airway inflammation, or both. This abstract is funded by: None