Finally, in Model 4, the association between IL-6 levels and MMSE score was also significant after adjustment for age (β = −0.15; 95% CI: −0.17 to −0.13), sex (β = −0.35; 95% CI: −0.63 to −0.08), educational level (β = 0.28; 95% CI: 0.25 to 0.32), BMI, LDL Cholesterol, AST, RBC, depression (β = −0.53; 95% CI: −0.93 to −0.14), CRP and TNF-α (β = 0.04; 95% CI: 0.01 to 0.07). Here, TNF is linked to major depressive disorder.