COVID-19 resulted in the largest cohort of critical illness survivors in history, heightened awareness of the importance of the respiratory sequelae after an acute distress respiratory syndrome (ADRS). Despite the advancement of acute-phase ARDS management, it is unknown whether there are differences in the longitudinal recovery trajectories between patients with post-ARDS due to COVID-19 and due to other causes. The main objective of the study is to identify risk factors of pulmonary sequela (lung diffusing capacity) at long-term follow-up in survivors of ARDS. The investigators are also interested in describing the long-term longitudinal recovery trajectories at a multi-dimensional level (symptoms, quality of life, neurocognitive, other lung function parameters, exercise capacity, chest imaging and molecular profiles) of ARDS survivors, and compared between ARDS caused by COVID-19. The ultimate goal is to understand the pathobiological mechanisms associated with a severe lung injury at the long term, allowing the introduction of clinical guidelines for the management of post-ARDS patients and the assignment of personalized interventions.