It’s confirmed: Dexamethasone does prevent deaths in COVID-19 patients, but only if they have significant lung disease.

Very good news today as the New England Journal of Medicine published a confirmatory clinical trial showing the benefit of using the steroid medicine dexamethasone to treat COVID-19 patients. The Recovery Collaborative Group conducted the research as a controlled, but open label trial comparing a number of different medications to treat COVID-19. The study was large comparing 2,104 patients that received either oral or intravenous dexamethasone, 6 mg. once a day for 10 days, to 4,321 patients who received usual care without the steroid. The results appear definitive.

The primary outcome was reduction in death. Overall, 482 patients (22.9%) in the dexamethasone group and 1,110 patients (25.7%) in the usual care group died within 28 days after they entered into the study (age-adjusted rate ratio, 0.83; P<0.001). This clearly indicated an overall benefit for patients treated with dexamethasone, and the results were also age adjusted and demonstrated the benefit no matter how old the patient.

What was interesting was that the benefit was only seen in patients who had lung disease severe enough to require oxygen. In fact, the benefit appeared to be greatest in patients with the most severe lung disease who required being placed on a ventilator. Dexamethasone resulted in lower 28-day mortality in patients who were receiving mechanical ventilation by 12.3%, a reduction in mortality of 1/3. The mortality reduction was 4.1% in those who required oxygen therapy without a ventilator, for a reduction of approximately 1/5). However, dexamethasone provided no benefit among patients who were not receiving respiratory support and suggested possible harm in this group of patients.

A smaller trial in Spain that was focused on patients with the most severe form of COVID-19 lung disease (ARDS or acute respiratory distress syndrome) had already indicated that dexamethasone reduced long term (60 day) mortality by 15%, which was similar to this study. 

Together, these studies strongly support the use of dexamethasone to treat COVID-19 patients with lung disease. Maybe more importantly, they also show the benefit of large, controlled trials to definitively document the benefit, and in this case the possible harm (in patients without lung disease) of a treatment like dexamethasone.