Dynamic Interleukin-6 Level Changes as a Prognostic Indicator in Patients With COVID-19

Abstract

Background: Interleukin-6 (IL-6), a proinflammatory cytokine, has been reported to be associated with disease severity and mortality in patients with coronavirus disease 2019 (COVID-19). Yet, dynamic changes in IL-6 levels and their prognostic value as an indicator of lung injury in COVID-19 patients have not been fully elucidated. Objective: To validate whether IL-6 levels are associated with disease severity and mortality and to investigate whether dynamic changes in IL-6 levels might be a predictive factor for lung injury in COVID-19 patients. Methods: This retrospective, single-center study included 728 adult COVID-19 patients and used data extracted from electronic medical records for analyses. Results: The mortality rate was higher in the elevated IL-6 group than in the normal IL-6 group (0.16 vs 5%). Cox proportional hazards and logistic regression analyses for survival (adjusted hazard ratio, 10.39; 95% confidence interval [CI], 1.09-99.23; p = 0.042) and disease severity (adjusted odds ratio, 3.56; 95% CI, 2.06-6.19; p < 0.001) revealed similar trends. Curve-fitting analyses indicated that patient computed tomography (CT) scores peaked on days 22 and 24. An initial decline in IL-6 levels on day 16 was followed by resurgence to a peak, nearly in tandem with the CT scores. Conclusion: Increased IL-6 level may be an independent risk factor for disease severity and in-hospital mortality and dynamic IL-6 changes may serve as a potential predictor for lung injury in Chinese COVID-19 patients. These findings may guide future treatment of COVID-19 patients.

<strong>Low-dose Whole-lung Irradiation for COVID-19 Pneumonia: What is the Optimal Dose? Final Results of a Pilot Study</strong>

“…The prognostic significance of CRP and IL-6 in patients with COVID-19 pneumonia has been demonstrated. 19,20 Considering the plasma half-life of CRP (19 hours) and IL-6 (10 minutes), they declined in 100% and 77.8% of available patients after 2 days and on the day of RT, respectively. 21,22 This highlights the anti-inflammatory effect of LD-WLI in patients with COVID-19 pneumonia.…”

Interleukin-6 Is a Biomarker for the Development of Fatal Severe Acute Respiratory Syndrome Coronavirus 2 Pneumonia

“…While homeostatic values of IL-6 contribute to the resolution of infections and tissue lesions, its exacerbated production contributes decisively to cytokine storms ( 22 – 24 ). In COVID-19, IL-6 has been positively correlated with disease stages and radiologic changes ( 17 , 25 – 27 ). Furthermore, the potential prognostic value of IL-6 has been explored regarding the need for mechanical ventilation, mortality, or both, when considered alone or in combination with other variables ( 28 – 32 ).…”

Gastrointestinal involvement attenuates COVID-19 severity and mortality

“…Several cytokines and other immunological parameters have been correlated with COVID-19 severity. Most notably, elevated IL-6, IL-8, IL-10, MCP-1 and IP-10 levels were detected in hospitalized patients, especially critically ill patients, in several studies, and are associated with ICU admission, respiratory failure, and poor prognosis 3,[30][31][32][33][34][35][36] . Alongside this proinflammatory cytokine environment, significant immune cell alterations have been described such as lymphopenia, T and B cell activation and exhaustion 37 , as well as altered frequencies of myeloid cells, including conventional dendritic cells (cDCs) and plasmacytoid dendritic cells (pDCs) 5,38,39 .…”