Efficacy of Additional Corticosteroids After Dexamethasone Treatment for Moderate to Severe COVID-19: An Observational Study.

Background Previous studies have demonstrated dexamethasone (DEX)'s efficacy for coronavirus disease 2019 (COVID-19). In contrast, patients with residual lung field shading and symptoms after DEX treatment have been observed, and the efficacy of additional corticosteroids (AC) is unknown. Objectives We aimed to investigate the efficacy of AC in patients with COVID-19 with residual respiratory symptoms or who required oxygen therapy or invasive mechanical ventilation after DEX treatment. Methods This was a single-center, retrospective observational study including 261 patients with community-onset COVID-19, aged ≥ 18 years, admitted to our hospital between March 1, 2020, and May 31, 2021. Finally, 34 patients were included in the study who met all four of the following criteria: (1) required oxygen therapy or invasive ventilation, (2) were treated with DEX, (3) had residual shading on chest imaging after DEX treatment, or (4) had unimproved respiratory symptoms or oxygen saturation < 90%. We reviewed the medical records and clinical courses of 14 patients who received AC therapy (AC group) and 20 patients who did not (non-additional corticosteroids or NC group). Results The 90-day mortality rate was 35.7% in the AC group and 25.0% in the NC group. There was no statistically significant difference between the two groups (p = 0.797). In addition, there was no difference between groups in the proportion of patients who required oxygen therapy at discharge (64% vs. 35%, p = 0.162). The time from the end of DEX therapy to discharge was significantly longer in the AC group (median 7.5 vs. 33 days, p = 0.019). Regarding serious adverse events, infection was statistically more common in the AC group than in the NC group (p = 0.005). Conclusions AC after DEX treatment does not improve clinical outcomes and may prolong hospital stay.