IL6 and depressive disorder: The interaction between acute changes in IL-6 (%T2-T1) and post-treatment IL-6 levels significantly predicted changes in affective symptoms of depression (%T3-T1), over and above the effects of age, sex, BMI and baseline/pre-treatment IL-6 levels (b = −.054, t [20] = -3.833, p = .001; model summary: R2 = .621, F [7,20] = 4.685, p = .003).