Evolution of Home Mechanical Ventilation in Sweden Over 27 Years: Changing Trends in Incidence, Prevalence, and Patient Characteristics - The Population-Based the Course of Disease in Patients Reported to the Swedish CPAP Oxygen and Ventilator Registry (DISCOVERY) Study.

Background: Home mechanical ventilation (HMV), noninvasive ventilation and invasive ventilation outside a hospital setting, is a key treatment to improve outcomes in chronic hypoventilation. Research Question: What are the temporal trends observed over 27 years in Sweden regarding the incidence, prevalence, diagnostic spectrum, and patient characteristics associated with HMV? Study Design and Methods: This was a national population-based longitudinal analysis of the Course of Disease in Patients Reported to the Swedish CPAP Oxygen and Ventilator Registry (DISCOVERY) study of patients initiating HMV between 1996 and 2022. Time trends stratified by the underlying diagnosis group (lung disease, predominantly COPD, restrictive thoracal diseases, obesity hypoventilation syndrome [OHS], neuromuscular diseases, amyotrophic lateral sclerosis, and other neurologic disorders) were analyzed using linear regression models. Results: We included 10,555 patients aged ≥ 16 years (mean age 63 [SD, 15] years; 50% women). Between 1996 and 1998 and 2020 and 2022, the HMV incidence increased threefold to 7 per 100,000 people, and the prevalence increased sixfold to 33 per 100,000 people. The most common indication for incident HMV shifted from restrictive thoracal diseases (35% in 1996-1998 to 3% in 2020-2022) to lung disease (14% to 31%), OHS (23% to 33%), and amyotrophic lateral sclerosis (4% to 14%) by 2020 to 2022 ( Interpretation: In the 27 years until 2022, the incidence and prevalence of HMV in Sweden have increased markedly, patient demographics have changed, and use of invasive ventilation has decreased. The average age of patients initiated on HMV has increased, but treatment is started earlier in the disease trajectory.