Dynamic changes in serum IL-6, IL-8, and IL-10 are associated with the outcome of patients with severe COVID-19 in ICU

• Measuring serum cytokines post ICU admission in 40 COVID-19 patients.  

• Retrospectively compared survivor vs non-survivor cytokine profiles, showed serum IL-6 and TNF-α higher in patients who died in ICU.  

• IL-6 has been proposed as COVID-19 biomarkers by several studies, but antagonistic IL-6 treatments have not shown definitive success in improving COVID-19 patient outcome. 

• IL-10 generally considered anti-inflammatory but has been noted to be higher in sepsis patients, proposed the increase might be an attempt to moderate the immune response. 

• This study provides useful information as to cytokine profile changes throughout COVID-19 disease. 

Research Highlights 

1. Various pro- and anti-inflammatory cytokines were measured over samples taken from 40 ICU patients over 14 day (or more) period. 

2. Timepoints were 1-3 days, 4-7 days, 8-13 days and 14 days onwards post ICU admission 

3. Survivor and non-survivor profiles were compared retrospectively. 

4. Serum IL-6, IL-10 and TNF-α was higher in severe cases where patients died. 

5. IL-6, IL-8 and IL-10 were significantly associated with patient outcome despite the confounding variables e.g. age, gender, neutrophil count. 

Impact for COVID-19 research:  

Could benefit disease management, looks at cytokine profile over time so could help identify high risk cases. 

Methodologies: 

• Study Type: Retrospective cohort study 

Limitations: 

• Only measured cytokines post-ICU admission, do not know if profiles differed before admission. 

• Limited sample size, and some patients were missing particular clinical measures e.g. neutrophil counts. 

•  Survival was only measured during ICU, no follow up on patients who were discharged from ICU to see if they died later.