The secondary aim was to find possible correlations between clinical factors and baseline serum IL1-beta, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12 p70, IFN-gamma, and TNF-alpha levels to find predictive markers of disease progression and diagnosis conversion from MDD to BD in young patients with clinical variables (impulsivity and defense mechanisms). The gene discussed is TNF; the disease is major depressive disorder.