London, Jun 19 (IANS): A team of UK scientists, led by an Indian-origin researcher, has found that Covid-19 patients with extremely high levels of stress hormone cortisol in their blood are more likely to deteriorate quickly and die.

The study from Imperial College London, published in The Lancet Diabetes & Endocrinology, provides the first data to show that cortisol levels are a marker of the severity of the illness.

The researchers suggest cortisol levels can be used to identify those patients who are more likely to need intensive care.

Cortisol is produced by the body in response to stress such as illness, triggering changes in metabolism, heart function and the immune system to help our bodies cope.

Our cortisol levels when healthy and resting are 100-200 nm/L and nearly zero when we sleep, the study said.

When ill patients have low levels of cortisol, it can be life-threatening. Excessive levels of cortisol during illness can be equally dangerous, leading to increased risk of infection and poor outcomes.

"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 lead researcher Waljit Dhillo from Imperial College London in the UK/

In the new observational study of 535 patients, of whom 403 were confirmed to have Covid-19, cortisol levels in patients with Covid-19 were significantly higher than in those without.

The levels in the Covid-19 group ranged as high as 3241 - considerably higher even than after major surgery when levels can top 1000.

The findings showed that among the Covid-19 patients, those with a baseline cortisol level of 744 or less survived on average for 36 days. Patients with levels over 744 had an average survival of just 15 days.

"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.

"Now, when people arrive at the hospital, 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," Dhillo explained.

"Having an early indicator of which patients may deteriorate more quickly will help us with providing the best level of care as quickly as possible, as well as helping manage the pressure on the NHS," he added.

In addition, we can also take cortisol levels into account when we are working out how best to treat our patients, the author wrote.

The research team hope that their findings can now be validated in a larger-scale clinical study.