Summary of COVID-19 dexamethasone studies
1. Horby et al., Dexamethasone in Hospitalized Patients with Covid-19
6,425 patient dexamethasone late treatment RCT: 13% lower mortality (p=0.005), 21% lower ventilation (p=0.03), and 9% higher hospital discharge (p=0.003).RCT 6,425 hospitalized COVID-19 patients showing lower 28-day mortality with dexamethasone treatment. The benefit was most pronounced in patients who had symptoms for more than 7 days at randomization, suggesting dexamethasone is most effective when the disease is dominated by inflammatory processes rather than viral replication. 6-month results are from [Horby]
Feb 2021, New England J. Medicine, http://www.nejm.org/doi/10.1056/NEJMoa2021436, https://c19p.org/horby5
2. Tomazini et al., Effect of Dexamethasone on Days Alive and Ventilator-Free in Patients With Moderate or Severe Acute Respiratory Distress Syndrome and COVID-19
299 patient dexamethasone late treatment RCT: 3% lower mortality (p=0.85) and 34% improvement (p=0.07).RCT 299 patients with moderate or severe COVID-19-related ARDS showing increased ventilator-free days with dexamethasone treatment. There was no significant difference in 28-day mortality (56.3% vs 61.5%), ICU-free days, or mechanical ventilation duration. The study protocol and the Statistical Analysis Plan (SAP) include reporting mortality at 3, 6, 9, and 12 months, however this was not done.
Oct 2020, JAMA, https://jamanetwork.com/journals/jama/fullarticle/2770277, https://c19p.org/tomazini
3. Mourad et al., Dexamethasone for Inpatients With COVID-19 in a National Cohort
56,368 patient dexamethasone late treatment study: 10% lower mortality (p=0.0002).PSM retrospective 80,699 hospitalized COVID-19 patients showing reduced mortality or discharge to hospice with dexamethasone in patients requiring supplemental oxygen or mechanical ventilation/ECMO, but no significant difference in patients not requiring supplemental oxygen or on NIPPV.
Apr 2023, JAMA Network Open, https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2803926, https://c19p.org/mourad2
4. Bhat et al., Effectiveness of Dexamethasone for COVID-19 in Hospitalized Patients With Diabetes: A Retrospective Cohort Study
1,058 patient dexamethasone late treatment PSM study: 35% higher mortality (p=0.2) and 46% worse improvement (p=0.02).Retrospective propensity score matched study of 529 hospitalized diabetic COVID-19 patients showing no significant difference in mortality or clinical improvement with dexamethasone treatment.
Oct 2024, The J. Clinical Endocrinology & Metabolism, https://academic.oup.com/jcem/advance-article/doi/10.1210/clinem/dgae734/7825467, https://c19p.org/bhat2
5. Jamaati et al., No clinical benefit of high dose corticosteroid administration in patients with COVID-19: A preliminary report of a randomized clinical trial
50 patient dexamethasone late treatment RCT: 7% higher mortality (p=1) and 18% higher ventilation (p=0.78).RCT 50 hospitalized COVID-19 ARDS patients showing no clinical benefit with high-dose dexamethasone.
Apr 2021, European J. Pharmacology, https://www.sciencedirect.com/science/article/pii/S001429992100100X, https://c19p.org/jamaati
6. Bepouka et al., Clinical Characteristics and Mortality Trends Among COVID-19 Patients During the First Four Waves in Ngaliema Clinic, Democratic Republic of the Congo
410 patient dexamethasone late treatment study: 104% higher mortality (p=0.55).Retrospective 410 hospitalized COVID-19 patients in the Democratic Republic of Congo showing significantly lower mortality with vitamin C treatment.
May 2025, Infection and Drug Resistance, https://www.dovepress.com/clinical-characteristics-and-mortality-trends-among-covid-19-patients--peer-reviewed-fulltext-article-IDR, https://c19p.org/bepoukadex
7. Yen et al., Predictors for cause-specific and timing of deaths in patients with COVID-19: a cohort study in Taiwan
2,196 patient dexamethasone late treatment study: 103% higher mortality (p=0.0002).Retrospective 2,196 COVID-19 patients in Taiwan (49% mild cases, 44% moderate, 7% severe) showing significantly higher mortality with dexamethasone.
Aug 2024, BMC Infectious Diseases, https://bmcinfectdis.biomedcentral.com/articles/10.1186/s12879-024-09654-w, https://c19p.org/yen3
8. Crothers et al., Dexamethasone in hospitalised COVID-19 patients not on intensive respiratory support
14,950 patient dexamethasone late treatment study: 59% higher mortality (p<0.0001).IPTW retrospective 19,973 hospitalized COVID-19 patients showing increased 90-day mortality with dexamethasone in patients not on oxygen and no mortality benefit in patients on low-flow nasal cannula. Authors found consistent results across multiple sensitivity analyses. Authors suggest that widespread adoption of dexamethasone for less severely ill COVID-19 patients may cause unintended harm, hypothesizing that early corticosteroid use may impair viral clearance and immune responses important for infection resolution.
Nov 2021, European Respiratory J., https://publications.ersnet.org/lookup/doi/10.1183/13993003.02532-2021, https://c19p.org/crothers
9. Garneau et al., Clinical effects of dexamethasone among patients with sickle cell disease hospitalized with COVID-19: Outcomes from a single academic health system
30 patient dexamethasone late treatment study: 423% higher ICU admission (p=0.14) and 155% longer hospitalization (p=0.06).Retrospective 30 hospitalized patients with sickle cell disease (SCD) showing increased risk of venous thromboembolism (VTE) with dexamethasone treatment for COVID-19. There were also trends towards increased ICU admission and longer hospital stays with dexamethasone, without statistical significance.
Nov 2024, PLOS ONE, https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0313289, https://c19p.org/garneau
1,749 patient dexamethasone late treatment RCT: 15% higher mortality (p=0.15) and 46% higher ventilation (p=0.27).
RCT 1,272 hospitalized COVID-19 patients with hypoxia receiving no oxygen or simple oxygen only, showing significantly increased mortality with higher dose dexamethasone compared to usual care (which included low-dose dexamethasone). 6-month results are from [Horby]
May 2023, The Lancet, https://www.sciencedirect.com/science/article/pii/S014067362300510X, https://c19p.org/horby13
11. Franco-Moreno et al., Effect of early administration of dexamethasone in patients with COVID-19 pneumonia without acute hypoxemic respiratory failure and risk of development of acute respiratory distress syndrome: EARLY-DEX COVID-19 trial
126 patient dexamethasone late treatment RCT: 134% higher ventilation (p=0.41), 217% higher ICU admission (p=0.46), 17% higher ARDS (p=0.81), and 3% shorter hospitalization (p=0.88).RCT 126 hospitalized COVID-19 pneumonia patients not requiring oxygen at admission, showing no significant difference in outcomes with dexamethasone treatment.
Jul 2024, Frontiers in Medicine, https://www.frontiersin.org/articles/10.3389/fmed.2024.1385833/full, https://c19p.org/francomorenodex
12. Kocks et al., A potential harmful effect of dexamethasone in non-severe COVID-19: results from the COPPER-pilot study
6 patient dexamethasone early treatment RCT: 600% worse recovery (p=0.07).Pilot RCT of 7 outpatients with non-severe COVID-19 suggesting potential harmful effects of dexamethasone treatment. Time to recovery was significantly longer in the dexamethasone group compared to controls (p=0.03). Authors note that systemic corticosteroids, while beneficial for hospitalized COVID-19 patients requiring oxygen, may be harmful in non-severe cases by potentially inhibiting normal immune response when administered too early.
Apr 2022, ERJ Open Research, https://publications.ersnet.org/lookup/doi/10.1183/23120541.00129-2022, https://c19p.org/kocks