FIGURE 4.

Association of host response biomarkers with ageing. a) Heatmap depicting the magnitude of biomarker differences (Hedges’ g) between patients ≥70 years compared with other age groups. p-values were obtained from a linear (if linear) or cubic spline regression analysis (if nonlinear) in which age was modelled as a continuous variable. The adjusted model included demographics, age-related comorbidities, age and biomarker-related chronic medication, and COVID-19-related immunomodulating treatments before sampling (see Methods for details). Red indicates higher levels in patients ≥70 years and blue indicates lower levels in patients ≥70 years. ^#: biomarkers with a nonlinear relationship with ageing on a continuous scale. b) Volcano plot depicting the strength of the correlation between a biomarker and ageing. Red dots represent a significant positive correlation, blue dots represent a significant negative correlation and grey dots represent a nonsignificant correlation. Both the adjusted and unadjusted p-values are multiple testing corrected using the Benjamini–Hochberg (BH) procedure for testing 43 biomarkers. *: p<0.05; **: p<0.01; ***: p<0.001. ANG: angiopoietin; sTie-2: soluble Tie-2; sE-selectin: soluble E-selectin; sThrombomodulin: soluble thrombomodulin; sVCAM-1: soluble vascular cellular adhesion molecule 1; PAI-1: plasminogen activator inhibitor 1; sCD31: soluble cluster of differentiation 31; sRAGE: soluble receptor for advanced glycation end-products; sTNF-R1: soluble tumour necrosis factor receptor 1; sTREM-1: soluble triggering receptor expressed on myeloid cells 1; SP-D: surfactant protein D; CD40L: CD40 ligand; PD-L1: programmed death ligand 1; CCL: C-C motif chemokine ligand; CXCL: C-X-C motif chemokine ligand; IL: interleukin; TNF: tumour necrosis factor; GM-CSF: granulocyte–macrophage colony-stimulating factor; IFN: interferon.