Causal effects of inflammatory biomarkers on all-cause mortality. Forest plot showing that higher IL6R is protective against mortality, whereas higher IL6 is harmful. CRP and GDF-15 are neutral. Abbreviations: IL6R: interleukin-6 receptor; IL6: interleukin-6; CRP: C-reactive protein; GDF-15: growth differentiation factor-15; OR: odds ratio; CI: confidence interval.