CXCL8 and COVID-19: For the subset of ICU patients (n = 42), the association between the pro-inflammatory cytokines (IL-6, IL-8, IP-10) and anti-inflammatory cytokine IL-10 levels and ICU mortality (Fig. 5e) was comparable to the association with hospital mortality of the entire Limburg COVID-19 cohort, but the majority of the associations were not significant.