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Dexamethasone, an anti-inflammatory and immunosuppressive prescription steroid used to treat various conditions, was one of the treatments used by President Donald Trump following his COVID-19 diagnosis and three-day stay at Walter Reed National Military Medical Center in early October. According to White House physician Sean Conley, Trump received two episodes of transient dexamethasone drops in his oxygen saturation two days after his admittance to the hospital. The drug mimics natural anti-inflammatory hormones produced by the body and has previously been used to treat a number of autoimmune diseases.
Jeffrey Sturek, pulmonary and critical care doctor and University assistant professor, noted last week that dexamethasone is not for patients with mild symptoms. Rather, it has been found to help those with extreme coronavirus cases, defined by patients with high oxygen requirements and in need of a ventilator.
“It did not help patients who did not require supplemental oxygen,” Sturek said in an email to The Cavalier Daily. “If anything, the direction of effect was towards harm in these milder cases.”
Sturek refers to a recent study — supported by a grant to the University of Oxford from the U.K. Research and Innovation and National Institute for Health Research — which used subgroup analysis to determine the effects of dexamethasone. Two specific patient populations were examined, and in total, 2,104 patients received dexamethasone and 4,321 received standard COVID-19 treatment, which varies depending on an individual patient’s situation and can include other drugs such as remdesivir.
Taison Bell — infectious disease physician and director of the U.Va. Intensive Care Unit, which also oversees the most severe COVID cases — explained that the first group consisted of patients within one week of COVID-19 symptom onset while the second group consisted of COVID-19 patients who had been experiencing symptoms for more than a week.
“Although the overall group of patients benefited from having the dexamethasone, when they looked at the subgroup analysis, patients that were within seven days of symptom onset did not have that benefit of improved hospital stay, or mortality, or any of the other clinical markers,” Bell said.
Overall, 23 percent of patients treated with dexamethasone died within 28 days while 26 percent of patients who received only standard COVID-19 care died. For patients taking the steroid on mechanical ventilation, which provides oxygen and aids in respiration, death tolls were one-third lower. For those taking the steroid in addition to receiving a non-invasive supply of oxygen to aid breathing, death tolls were one-fifth lower than when compared to patients that did not require oxygen.
Bell explained that in the early stages of one’s response to COVID-19, the immune system is what prevents the viral load from getting too high. As an immunosuppressant, dexamethasone is introduced to reduce the inflammation triggered when the immune system attempts to fight off the SARS-CoV-2 infection. Though a reduction in inflammation can improve a patient’s status, the drug can also cause the immune system to go into a fatal overdrive. This overworking of the immune response recruits an excess of white blood cells to the lungs causing fluid backup.
“It's kind of like a car that has the gas pedal stuck,” Bell said. “Your inflammatory drive is so ramped up that it causes actual damage to your healthy body tissues.”
Though the reasons for the different responses seen in mild versus severe cases is not completely understood at the present moment, Sturek guesses that it is due to the ways in which the immune system responds at different points of infection.
“My guess would be that in severe cases, the dexamethasone is preventing the immune system from overreacting and causing inflammation in the lungs,” Sturek said. “In mild cases, it may prevent protective immune responses … that help clear the virus early on in disease.”
Sturek mentioned that dexamethasone can also come with harmful side effects such as increased blood glucose, which makes it harder for diabetics to manage, fluid retention, difficulty sleeping, agitation, irritability and increased appetite.
Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, announced his support of dexamethasone in treating extreme cases of COVID-19, though similarly to Sturek and Bell, states that suppressing the immune system early on is an unnecessary risk.
Studies are ongoing to test the effectiveness of dexamethasone for treatment of COVID-19.