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

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.