Modulation of cytokine response in post-cardiac arrest syndrome through prehospital high-dose glucocorticoid treatment

Abstract Funding Acknowledgements Type of funding sources: Foundation. Main funding source(s): Novo Nordisk Foundation Research Foundation of Rigshospitalet. Background Post-cardiac arrest syndrome (PCAS) following out-of-hospital cardiac arrest (OHCA) is a life-threatening condition, characterized by a cascade of pathological events, including the development of a severe cytokine response. This inflammatory response may be associated with secondary brain injury and multi-organ dysfunction. In the randomized STEROHCA trial, high-dose glucocorticoid was administered immediately following resuscitation in the prehospital setting. The intervention exhibited a significant decrease in interleukin (IL) 6 levels, but its effect on other cytokines has yet to be assessed. Purpose We aimed to investigate the effects of high-dose glucocorticoid treatment in mitigating the cytokine response observed in PCAS after OHCA. Methods The modified intention-to-treat population of the double-blind, randomized STEROHCA trial consisted of 137 OHCA patients, who were randomized to a single prehospital injection of methylprednisolone 250 mg or placebo. Of these, this sub-study included 112 patients who were comatose and admitted to an ICU. Cytokine profiling was performed with a 17-plex assay, including pro- and anti-inflammatory cytokines, which were measured at 0, 24, 48, and 72h after admission. We applied mixed-model analyses to assess the effect of the intervention over time with log-transformed data. To maintain an exploratory approach, we chose not to correct for multiple testing. Results The intervention induced a reduction in the levels of several cytokines, with a significant treatment over time effect for IL-4, IL-8, IL-10, Monocyte Chemoattractant Protein-1 (MCP-1), Macrophage Inflammatory Protein-1 Beta (MIP-1β), and Tumor Necrosis Factor Alpha (TNF-α), all p0.01. These cytokines, except for IL-10, exhibited lower values in the glucocorticoid group after 24h, Figure 1. Higher levels of IL-10 were observed in the glucocorticoid group at 0h. We found no differences in cytokine levels after 48-, and 72h between the two groups. Conclusion High-dose glucocorticoid treatment administered promptly after resuscitation from OHCA reduced several pro-inflammatory cytokines after 24h. TNF-α has previously been associated with poor outcomes following OHCA, whereas the exact role of the other cytokines following OHCA is unclear.Cytokines at 0-, 24-, 48-, and 72 hours