Impact of Schizophrenia on Outcomes Following Non-Invasive Ventilation for Acute Hypercapnic Respiratory Failure in COPD

Limited data describe outcomes in people with comorbid schizophrenia when admitted with acute hypercapnic respiratory failure (AHRF). This study compared outcomes in people with COPD requiring non-invasive ventilation (NIV), with and without schizophrenia, to identify priorities for intervention and research. This is a retrospective cohort study from a single Australian quaternary referral hospital of people with COPD requiring NIV for AHRF over 5 years from 1 January 2017 to 31 December 2024, excluding admissions between 1 January 2020 and 31 December 2022, when the COVID-19 pandemic disrupted usual practices. Primary outcomes were length of stay (LOS) and NIV duration (days). Secondary outcomes included NIV discontinuation reason, challenges to NIV and readmission. Descriptive and comparative statistics summarised variables by schizophrenia status and assessed between-group differences. Cox proportional hazards models assessed survival, while association between schizophrenia and readmission was analysed using competing-risks regression. Prevalence of schizophrenia is higher in this cohort than general population, comprising 36 (19%) of 186 individuals, and 97 (30%) of 328 admissions. Those with schizophrenia were younger (66.6 vs. 72.5 years, p = 0.001), with more current smokers (75% vs. 42.7%, p = 0.005) and had admissions with shorter LOS (6 vs. 9 days, p = 0.043) and NIV duration (3 vs. 5 days, p = 0.021). There was no significant difference in reason for NIV discontinuation between the groups. Readmission rates were higher in the schizophrenia group (44.4% vs. 24.0%, p = 0.025). Age at death was lower for those with schizophrenia (67.3 vs. 77.4 years, p < 0.001). People with schizophrenia had shorter LOS and NIV use, higher readmission rates, higher prevalence of current smokers and younger age at presentation and death. These findings suggest that schizophrenia is an at-risk subgroup in AHRF, highlighting the need for collaborative action.