Body mass index and heart failure define survival phenotypes in COPD patients on home mechanical ventilation - the population-based DISCOVERY study

Background: Home mechanical ventilation (HMV) improves survival in selected patients with hypercapnic chronic obstructive pulmonary disease (COPD). The generalisability of trial data to the broader COPD population, often characterised by multimorbidity and obesity, remains uncertain. Objectives: To identify clinical phenotypes among COPD patients treated with HMV in Sweden and examine how mortality differs across these subgroups. Methods: This longitudinal, population-based study included adults with COPD initiating HMV reported to the national Swedevox registry between 1996 and 2022, linked with national registry data. Cluster analysis using the partitioning around medoids (PAM) method with Gower’s distance identified patient phenotypes based on ten variables, including age, body mass index (BMI), lung function, heart failure (HF), obesity hypoventilation/restrictive thoracic disease, depression, and previous hospitalisations. Mortality was assessed across clusters. Results: Among 2,011 patients (64% female; mean age 69 ± 10 years; mean FEV₁ 32 ± 13% predicted), 24% died within one year of HMV initiation. Five clusters were identified, primarily distinguished by BMI and HF: Cluster 1 Obese with HF (n = 345, 23% mortality), Cluster 2 Obese without HF (n = 421, 16%), Cluster 3 HF with normal weight (n = 427, 29%), Cluster 4 Normal weight without HF (n = 474, 21%), and Cluster 5 Underweight (n = 344, 37%). Conclusion: Distinct COPD phenotypes receiving HMV show substantial differences in survival. BMI and the presence of heart failure were identified as key variables defining clusters.