IL6 and respiratory failure: The association between respiratory failure and higher levels of IL-1ra, IL-6, IL-8, MCP-1, MIP-3α, and MIP-3β persisted, and again MCP-1 was the cytokine with the highest estimate (OR 16.15, CI 4.02–64.86), followed by IL-6 (OR 8.30, CI 2.84–24.23), and IL-8 (OR 3.83, CI 1.78–8.21).