Single center, tertiary care, and pulmonary rehabilitation (Groningen, The Netherlands)
Moderate to very severe airflow limitation Referred for rehabilitation
Age, BMI, quadriceps force, body plethysmography, and exercise testing
Not assessed
K-means
2 phenotypes: (i) worse lung function and exercise capacity, worse quadriceps force, and better response to exercise training (ii) better lung function and exercise capacity and less response to exercise training
High or low improvement in endurance exercise capacity rehabilitation
Multicenter cohort (Initiatives BPCO), and tertiary care (France)
Mild to very severe airflow limitation Outpatients
Age, history, and symptoms, spirometry, BMI, exacerbations, health status, psychological status
Physician-diagnosed Not included in the cluster analysis
PCA, HCA (Ward’s)
4 phenotypes: (i) young subjects with severe respiratory disease, cachexia (ii) older subjects with mild airflow limitation and mild comorbidities (iii) young subjects with moderate to severe airflow limitation, but few comorbidities (iv) older subjects with moderate to severe airflow limitation and high rates of cardiovascular comorbidities
Mild to very severe airflow limitation Outpatients and COPD patients identified as part of a lung cancer screening study
Age, history and symptoms, health status, body plethysmography, DLCO, CT-scan, and physician-diagnosed comorbidities
Physician-diagnosed Included in the cluster analysis
PCA, MCA, HCA (Ward’s)
3 phenotypes: (i) younger patients with severe respiratory disease, cachexia, and low rates of cardiovascular comorbidities. (ii) older patients with less severe airflow limitation, but often obese and with high rates of cardiovascular comorbidities and diabetes. (iii) mild to moderate airflow limitation, absent or mild emphysema, absent or mild dyspnoea, normal nutritional status, and limited comorbidities
Population-based survey (Utrecht, The Netherlands)
Mild to moderate airflow limitation COPD patients identified as part of a lung cancer screening study
History and symptoms, health status, comorbidities, spirometry, DLCO, CT-scan, and breathomics (electronic nose)
Self-reported Included in the cluster analysis
PCA, HCA (Ward’s), K-means
4 possible phenotypes: (i) mild COPD (ii) moderate airflow obstruction with chronic bronchitis and emphysema (iii) asymptomatic emphysema with preserved lung function (iv) high symptoms, preserved lung function
Single center, tertiary care, pulmonary rehabilitation (Horn, The Netherlands)
Moderate to very severe airflow limitation Referred for rehabilitation
13 comorbidities
Systematically assessed Cluster analysis performed exclusively on comorbidities
SOM, HCA (Ward’s)
5 possible comorbid phenotypes: (i) less comorbidity (ii) cardiovascular (iii) cachectic (iv) metabolic (v) psychological with no difference in systemic inflammation
None
Type of cluster analysis not described; HCA: hierarchical cluster analysis; PCA: principal component analysis; MCA: multiple correspondence analysis; MDS: multidimensional scaling; SOM: self-organizing maps.