Bronchiectasis exacerbations (BEX) might differ in terms of signs and symptoms (S/S) at presentation, biological mechanisms and outcomes. To explore possible BEX phenotypes, a symptom-based cluster analysis with multidimensional scaling and hierarchical clustering was conducted among BE patients undergoing a physician-defined exacerbation who were enrolled in the EMBARC exacerbation sub-study.Patients? features and outcomes were compared across clusters.
Among 321 (62.6% female, median age 64 years) patients from 15 countries, 3 clusters were identified:cluster 1 (67.9%) included patients predominantly with cough and increased sputum volume and purulence;cluster 2 (12.2%) those with prevalent dyspnoea and wheezing;cluster 3 (19.9%) those who were paucisymptomatic with predominant symptoms of worsening dry cough and malaise.Patients? features during stable state were compared among clusters (table).Eosinophilia and comorbid asthma were more common in cluster 2.Severity of bronchiectasis using the BSI was similar in each cluster.More patients in cluster 2 received steroid treatment during the exacerbation (P:0.002).30-day mortality was significantly higher in cluster 2 (9.7%) compared to clusters 1 (1.0%) and 3 (0.0%), P:0.029.
| Cluster 1 "Green spitters" (218) |
Cluster 2 "Wheezers" (39) |
Cluster 3 "Paucisymptomatic" (64) |
p | |
| Female % | 62.4 | 61.5 | 64.1 | 0.968 |
| Median age | 62.5 | 65.0 | 66.5 | 0.097 |
| Median BSI | 9 | 9 | 8 | 0.255 |
| Asthma % | 25.2 | 51.3 | 39.1 | 0.002 |
| Eosinophilia % | 6.7 | 26.7 | 13.0 | 0.050 |
Conclusion:We described 3 clinical phenotypes of BEX with potentially different underlying biology.
Acknowlegments:EMBARC has received support from the EU/EFPIA Innovative Medicines Initiatives Joint undertaking iABC grant agr 115721