T‐helper 1/T‐helper 2 cytokine imbalance and clinical phenotypes of acute‐phase major depression

Abstract
Several studies have discussed the relationships between T-helper 1 (Th1) or Th2 cytokines and major depression. The aim of the present study was to investigate the relationships between Th1/Th2 cytokine balance and clinical phenotypes of acute-phase major depression. A total of 82 subjects including 42 patients with major depressive disorder and 40 healthy controls were recruited. Serum cytokine levels of interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α) and IL-10 were examined. Using ancova with age and body mass index (BMI) adjustments, there were no significant differences in serum IL-1β, TNF-α, and IL-10 levels between patients with major depressive disorder and healthy controls. However, using ancova with BMI adjustment only, the results showed that patients with major depressive disorder had significantly higher TNF-α levels than control subjects. In addition, using ancova with age and BMI adjustments, significantly higher serum IL-1β level and IL-1β/IL-10 ratio were noted in patients with melancholic features than patients with non-melancholic features. However, there were no significant differences in serum IL-1β, TNF-α and IL-10 levels between patients with and without suicide attempt. In conclusion, serum TNF-α, IL-1β level and IL-1β/IL-10 ratio might play an important role in the psychopathology of acute-phase major depressive disorder.