Efficacy of Standard Dexamethasone Therapy and Predictors for Nonresponsiveness to the Treatment in Patients with COVID-19 = Efficacy of Standard Dexamethasone Therapy and Predictors for Nonresponsiveness to the Treatment in Patients with COVID-19

다국어 초록 (Multilingual Abstract)

Purpose
Corticosteroid use is recommended in patients with coronavirus disease 2019 (COVID-19) requiring oxygen therapy. Current guidelines suggest typical daily doses of 6mg dexamethasone as the standard treatment, irrespective to the severity of respiratory failure. This study was aimed to investigate general efficacy of standard dexamethasone therapy and predictors for non-responsiveness to the treatment.
Method
This retrospective study reviewed patients with COVID-19 who were admitted Severance Hospital, between February 2020 and August 2021. We recruited 108 of consecutive participants who were initiated on 6mg daily dose of dexamethasone therapy during hospital stay. Patients who discontinued or tapered dexamethasone following the treatment were defined as responders. On the other hand, patients who increased the corticosteroid dose or expired during the therapy were defined as non-responders. Descriptive and inferential statistics were used to evaluate the treatment efficacy and predictors for nonresponsiveness to the treatment.
Result
Among the 108 participants, 71 (65.7%) were responders, and 37 (34.3%) were non-responders. In the non-responders, severe hypoxia requiring high-flow nasal cannula (HFNC) or mechanical ventilation (MV) was more common, lymphocyte count was lower at the baseline (p < 0.05). The 28-day mortality rate was higher in the non-responder group (10.8% vs. 1.4%, p = 0.046). Multivariate logistic regression showed that severe hypoxia requiring HFNC or MV, lower blood lymphocyte count, and higher serum CRP level at the baseline were the predictors for non-responsiveness to the treatment (p < 0.05). Among the non-responders without missing value (n = 32), 17 (53.1%) patients showed ≥50% improvement in PaO2/FiO2 ratio after the treatment with increased doses of corticosteroids (Figure 1).
Conclusion
About one-third of the participants showed non-responsiveness to the standard dexamethasone therapy and treated with higher doses of corticosteroids. Initial therapy with higher doses of corticosteroids might be considered in patients with predictors for non-responsiveness.