Epidemiological trends of mechanically ventilated acute respiratory distress syndrome in the twenty-first century: a nationwide, population-based retrospective study.

Purpose: Acute respiratory distress syndrome (ARDS) is a prevalent respiratory condition associated with significant mortality. Current literature on ARDS epidemiology reports a wide range of incidence (7.2-78.9/100,000 population/year), hospital mortality (32-51%), and associated costs ($8476-$547,974). We have analyzed epidemiological trends of mechanically ventilated ARDS (MV-ARDS) in Spain from 2000 to 2022 using the Minimum Basic Data Set (MBDS), focusing on MV-ARDS incidence, associated mortality, and economic impact.

Methods: We conducted a nationwide, population-based retrospective study of all hospitalizations for MV-ARDS in Spanish hospitals-from January 1, 2000 to December 31, 2022-using MBDS records, with an estimated coverage of 99.5%. The study reports MV-ARDS incidence per 100,000 population/year, hospital mortality rate, and mean cost per patient. We also considered the effect of COVID-19 on MV-ARDS epidemiology.

Results: We analyzed 93,192 records of patients with a new diagnosis of MV-ARDS during the study period. MV-ARDS incidence ranged from 2.96 to 20.14/100,000 population-years, peaking in 2021. Mortality ranged between 38.0 and 55.0%, showing a declining trend, while the cost per patient increased, stabilizing ~€30,000-€40,000 after reaching a peak of €42,812 in 2011. During the COVID-19 pandemic, hospital stay lengthened (p < 0.001), while hospital mortality decreased (p < 0.001). There was an increased proportion of patients with obesity and diabetes mellitus, with fungal or viral etiologies.

Conclusion: This is the largest epidemiological study on ARDS in Europe. MV-ARDS incidence has stabilized in recent years, with mortality showing a declining trend. ARDS-related costs have increased nearly fourfold. MBDS data could enhance ARDS understanding and guide future studies.