Clinical phenotypes in adult patients with bronchiectasis

Abstract

Bronchiectasis is a heterogeneous disease. This study aimed at identifying discrete groups of patients with different clinical and biological characteristics and long-term outcomes.This was a secondary analysis of five European databases of prospectively enrolled adult outpatients with bronchiectasis. Principal component and cluster analyses were performed using demographics, comorbidities, and clinical, radiological, functional and microbiological variables collected during the stable state. Exacerbations, hospitalisations and mortality during a 3-year follow-up were recorded. Clusters were externally validated in an independent cohort of patients with bronchiectasis, also investigating inflammatory markers in sputum.Among 1145 patients (median age 66 years; 40% male), four clusters were identified driven by the presence of chronic infection with Pseudomonas aeruginosaor other pathogens and daily sputum: "Pseudomonas" (16%), "Other chronic infection" (24%), "Daily sputum" (33%) and "Dry bronchiectasis" (27%). Patients in the four clusters showed significant differences in terms of quality of life, exacerbations, hospitalisations and mortality during follow-up. In the validation cohort, free neutrophil elastase activity, myeloperoxidase activity and interleukin-1β levels in sputum were significantly different among the clusters.Identification of four clinical phenotypes in bronchiectasis could favour focused treatments in future interventional studies designed to alter the natural history of the disease.

Neutrophil Elastase Activity Is Associated with Exacerbations and Lung Function Decline in Bronchiectasis

“…We observed strong relationships between NE activity and bacterial load. NE activity was also highest in patients with P. aeruginosa infection, and this was consistent with previous studies in bronchiectasis that showed that bacteria, and P. aeruginosa in particular, were the key drivers of airway neutrophilic inflammation (22), and that that P. aeruginosa infection represented a distinct clinical phenotype associated with earlier mortality, more frequent exacerbations, and worse quality of life (14,22,29,30).…”

Quality standards for the management of bronchiectasis in Italy: a national audit

“…On one hand, we can speculate that frequent exacerbators are also those with either an intermittent infection with P. aeruginosa or chronic infections with other bacteria, as recently reported [8], and that microbiology is just one of several bronchiectasis features responsible for bad outcomes [7]. On the other hand, hospitalisations for LRTI in bronchiectasis patients might be also due to factors not strictly related to bronchiectasis and infection, such as the presence of decompensated comorbidities or failure of oral antibiotic therapy [9].…”

Research priorities in bronchiectasis: a consensus statement from the EMBARC Clinical Research Collaboration

“…P. aeruginosa colonisation defines a specific clinical phenotype of bronchiectasis, and is associated with a three-fold increase risk of death, a nearly seven-fold increase risk of hospital admissions, worse quality of life and more frequent exacerbations [27][28][29]. Evidence from CF suggests that attempts at eradication therapy targeting Pseudomonas can have success in converting patients to culture-negative status [30].…”