Long-term cognitive dysfunction after COVID ARDS

Background: COVID-19 acute respiratory distress syndrome (C-ARDS) survivors suffer from long-term physical complications. However, at the time of this study limited data are available on possible long-term cognitive impairment. Objectives: We hypothesized that COVID-19 ICU patients perform worse on cognitive tasks 6 months after admission, in comparison to reference values of a healthy population. Design: Two-center cohort study with a six months’ time horizon. Patients: Patients admitted to the ICU for COVID-19 associated respiratory failure between March and June 2020. Setting: Post-ICU follow up. Methods and main outcome measures: The primary measure was the Repeatable Battery for Assessment of Neuropsychological Status (RBANS) score (with lower values indicating worse global cognition). The secondary outcome measure was the Trail Making Test (TMT) Part B (population age-, sex-, and education-adjusted mean score, 50±10, with lower scores indicating worse executive functions). The Short Form of the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE, on a scale from 1.0 to 5.0, with 5.0 indicating severe cognitive impairment) was taken for not patients not fluent in Dutch. Results: 117 COVID-19 patients were admitted to the ICU, of whom 32 patients (27%) died within 6 months. 67/85 (79%) patients participated in the cohort study. COVID-19 survivors had lower total RBANS cognition scores than the age-adjusted population norms (n=45). Fifteen (33%) patients had a global cognition score 1.5 SD below the population means. RBANS-subscale performance showed that both memory (immediate and delayed recall) and attention were at minus 1 SD below normative means, while language and visuospatial cognition were unaffected. Median TMT B score was 40 (IQR 10-65) (n=45). There were elevated scores of the short form IQCODE (mean 3.4 (SD 0.4). Conclusions: Our results suggests that COVID-19 ARDS negatively affects long-term cognitive function. Trial registration: ClinicalTrials.gov NCT04593069.