CXCL8 and major depressive disorder: <h4>Objective</h4>This study aims to ascertain the effect of baseline IL-1Ra and IL-8 in the treatment response of patients with major depressive disorder (MDD) and to clarify the relationship between inflammation markers and depression.<h4>Methods</h4>We recruited 242 patients with a Beck Depression Inventory (BDI) score ≥ 17 referred to secondary care in Finland.