Cluster Analysis of Home Mechanical Ventilation in COPD Patients: A Picture of the Real World and Its Impact on Mortality Jessica González; Paola Carmona; Esther Gracia-Lavedan; Iván D. Benítez; Antonio Antón; Anna Balaña; Sonia Belda Díaz; Òscar Bernadich; Ana Córdoba; Cristina Embid; Mireia Espallargues; Manel Luján; Sergi Martí; María Pilar Ortega Castillo; Julia Tárrega; Ferrán Barbé; Joan Escarrabill;