PURPOSE: Corticosteroids decrease mortality in patients with COVID-19 in need of oxygen therapy. However, corticosteroids are known to increase the risk of delirium in older patients. We studied whether dexamethasone increased the risk of delirium in older patients hospitalized with COVID-19. METHODS: Single centre, retrospective cohort study including patients ≥ 70 years hospitalized in a large teaching hospital with COVID-19 during the first (control group) and second wave (dexamethasone group, receiving dexamethasone) of the COVID-19 pandemic. Only patients on regular (non-ICU) wards were included. Delirium was defined as having a mean delirium observation screening (DOS)-score of ≥ 3 or having an altered mental state on day 3 of admission. RESULTS: We included 233 patients. The mean age in the dexamethasone group was 78.83 years [SD 6.5] compared to 79.43 years [SD 6.3] in the control group. In the dexamethasone group (n = 114), less patients developed delirium compared to the control group (n = 119) on day 3 of admission (5.3% vs 15.1%
p = 0.01). The Odds ratio of dexamethasone use for delirium was 0.23 (95% CI 0.08-0.64). CONCLUSION: In this study, dexamethasone did not increase the risk of delirium in older patients with COVID-19.