High-dose corticosteroid therapy in COVID-19: the RECOVERY trial

Numerous clinical studies reported extensive inflammation, cytokine storm, and immunopathology in critically ill patients with fatal COVID-19 compared with lower inflammatory responses in COVID-19 patients with mild to moderate disease.2 Dexamethasone treatment reduces neutrophil influx, blocks T-cell response, and diminishes cytokine storm; however, excessive doses can potentially trigger immunosuppression.3 The earlier RECOVERY trial found significant protection with low-dose dexamethasone treatment (6 mg per day) in severely ill COVID-19 patients.4 COVID-19 patients recruited in this earlier trial received oxygen or no oxygen and displayed characteristics of mild to moderate disease—thus, extreme caution was taken in selecting the dosage of dexamethasone to prevent dexamethasone-induced immunosuppression in these patients. [...]although initial C-reactive protein concentrations of over 75 mg/L were measured in the inclusion criteria of patients, follow-up tests on C-reactive protein concentrations during this 28-day trial were unclear. Fourth, it is unclear whether the patients with high-dose dexamethasone treatment discharged after the 28-day trial period had prolonged complications such as hyperglycaemia or other superinfections. Since dexamethasone treatment is known to prolong immune deficiency and induce hyperglycaemia, post-recovery monitoring for several months to assess the deleterious effects of dexamethasone in these patients is essential.