Correlation between peripheral inflammatory cytokines and anxiety symptoms in patients with the first-episode generalized anxiety disorder

Objective To investigate the relationship between peripheral inflammatory cytokines and anxiety symptoms in patients with the first-episode generalized anxiety disorder. Methods 48 patients diagnosed with the first-episode generalized anxiety disorder according to ICD-10 criteria and 48 healthy subjects were recruited.Peripheral levels of IL-1, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12p70, GM-CSF and IFN-γ of both groups were evaluated by enzyme-linked immunosorbent assay (ELISA), and CRP was evaluated by immunoturbidimetric method. Generalized Anxiety Disorder Scale(GAD-7) and State-Trait Anxiety Inventory(STAI)were used to assess the levels of overall anxiety, state anxiety and trait anxiety. Results The levels of CRP((1.19±0.80)mg/L vs (0.68±0.70)mg/L, t=3.31), IL-1α((70.34±3.60)pg/ml vs (16.94±3.42)pg/ml, t=74.50), IL-2((7.25±3.42)pg/ml vs (4.95±2.31)pg/ml, t=3.85), IL-4((102.02±73.14)pg/ml vs (75.55±32.78)pg/ml, t=2.29), IL-6((12.55±2.37)pg/ml vs (2.71±1.35)pg/ml, t=14.79), IL-8((44.64±16.21)pg/ml vs (35.69±11.70)pg/ml, t=3.10), IL-12((18.16±24.17)pg/ml vs (10.82±4.72)pg/ml, t=2.06), IFN-γ((23.32±15.52)pg/ml vs (16.48±6.80)pg/ml, t=2.79), GM-CSF((19.07±11.12)pg/ml vs (13.40±8.54)pg/ml, t=2.80) in patients with the first-episode generalized anxiety disorder were significantly higher than normal controls(P<0.05). Both SAI and TAI had significantly positive correlation with the levels of IL-1α, IL-2, IL-6, IL-8, IL-12, IFN-γ and GM-CSF(r=0.24-0.76, P<0.05). Conclusion The levels of some peripheral inflammatory cytokines in patients with the first-episode generalized anxiety disorder are significantly increased, and they have positive correlation with general anxiety, state anxiety and trait anxiety, which may suggest some immune system defects in the patients. Key words: Generalized anxiety disorder; State anxiety; Trait anxiety; Inflammatory cytokines