Stress levels may be a key factor in determining who suffers from severe COVID-19 and could potentially help measure who is at an increased risk of mortality. In a study conducted in London, researchers took the cortisol levels within 48 hours of hospital admittance in suspected COVID patients. Those who did not have COVID became the control group. Of the suspected patients admitted, 403 patients were found to have COVID. 

After analyzing the results, researchers found that the mean cortisol levels in COVID patients was 619 nmol/L versus 519 nmol/L in non-COVID patients. In addition, in patients with higher cortisol levels, a 43% increase in mortality was observed. Those with cortisol levels greater than 744 nmol/L had a median survival of 15 days versus 36 days in those with cortisol levels less than 744 nmol/L. MedRxIV

Takeaway: Researchers noted that stress levels observed in some COVID patients were higher than those observed in patients undergoing major surgery. The study conclusions state that elevated cortisol levels measured at hospital admittance can help in determining the sickest COVID patients who are the most likely to suffer from poor outcomes.

While this study is fascinating and gives us a glimpse of how stress levels may be elevated in severely ill COVID patients, researchers stress that using cortisol as a biomarker for COVID is not yet clinically proven. More studies are needed to link elevated cortisol levels to severe COVID.