High levels of the stress hormone cortisol are associated with an increased risk of death among COVID-19 patients, according to a new study.
The findings could be used to identify COVID-19 patients who are more likely to require intensive care, the researchers suggested.
Cortisol levels can rise when the body is stressed due to illness. High levels are dangerous, leading to increased risk of infection and poor outcomes.
In order to assess how high cortisol levels affect COVID-19 patients, U.K. researchers assessed 535 patients with suspected COVID-19 who were admitted to three London hospitals between March 9 and April 22.
A COVID-19 swab test and routine blood tests, including a baseline measurement of cortisol levels, were performed within 48 hours of admission. Cortisol levels were significantly higher in the 403 patients confirmed to have COVID-19 than in those without the illness, the findings showed.
Cortisol levels when a person is healthy and resting are 100 to 200 nm/L, and nearly zero during sleep. Levels in the COVID-19 patients in the study were as high as 3,241, much higher even than after major surgery, when levels can exceed 1,000.
Just under 27% of the COVID-19 patients died during the study period, compared to just under 7% of those without COVID-19, the researchers said.
Among the COVID-19 patients, those with a baseline cortisol level of 744 or less survived an average of 36 days, compared with 15 days for those with levels over 744, according to the study.
"From an endocrinologist's perspective, it makes sense that those COVID-19 patients who are the sickest will have higher levels of cortisol, but these levels are worryingly high," said study leader Waljit Dhillo.
Dhillo heads the diabetes, endocrinology and metabolism division at Imperial College London.
"Three months ago when we started seeing this wave of COVID-19 patients here in London hospitals, we had very little information about how to best triage people," Dhillo said in a college news release. Now, "we potentially have another simple marker to use alongside oxygen saturation levels to help us identify which patients need to be admitted immediately, and which may not."
Having an early indicator of which patients may deteriorate more quickly will help medical personnel provide the best level of care as fast as possible, Dhillo added.
The results were published June 18 in The Lancet Diabetes & Endocrinology.
The U.S. Centers for Disease Control and Prevention has more on COVID-19.