MONDAY, Sept. 18, 2023 (HealthDay News) -- For patients with bronchiectasis, increasing sputum purulence is associated with degree of inflammation and can predict outcomes, according to a study presented at the European Respiratory Society International Congress 2023, held from Sept. 9 to 13 in Milan.
Megan Crichton, Ph.D., from the University of Dundee in the United Kingdom, and colleagues collected long-term outcome data using a 4-point sputum color chart (Murray scale) in the EMBARC registry, which reviews bronchiectasis patients annually. A total of 19,324 patients from 31 countries were enrolled.
Overall, 13,484 patients reported regular sputum expectoration with a sputum color grade. Overall, 40.4, 39.9, 18.4, and 1.3 percent had mucoid sputum, mucopurulent, purulent, and severe purulent, respectively. The researchers found that higher Bronchiectasis Severity Index scores, lower forced expiratory volume in 1 second, and more frequent chronic infection, including with Pseudomonas aeruginosa, were seen in patients with more purulent sputum. Baseline sputum color was strongly predictive of future exacerbations during five years of follow-up. Patients with more purulent sputum experienced more exacerbations compared with those with mucoid sputum (incidence rate ratios, 1.26, 1.45, and 1.54, respectively). For severe exacerbations (hospitalization), similar results were observed (incidence rate ratios, 1.29, 1.73, and 2.01, respectively). There was a significant increase observed in mortality with increasing sputum purulence (hazard ratio, 1.12).
"Sputum samples can be easily collected from most patients, and the color has shown to be a useful indicator, thereby making sputum a readily available and easy-to-interpret clinical biomarker for disease progression," Crichton said in a statement.