Inflammatory cytokines, complement factor H and anhedonia in drug-naive major depressive disorder

Objective: Anhedonia is a core symptom of major depressive disorder (MDD) and often associated with poor prognosis. The main objective of the present study was to explore the relationship between complement factor H (CFH), inflammatory cytokines and anhedonia in drug-naive MDD patients. Methods: A total of 215 participants (61 MDD patients with anhedonia, 78 MDD patients without anhedonia, and 76 control subjects) were included. Severity of depression and levels of anhedonia were evaluated by Hamilton Rating Scale for Depression-17 (HAMD-17) and SHAPS (Snaith-Hamilton Pleasure Scale). Plasma levels of CFH, interleukin-6 (IL-6), IL-10 and tumor necrosis factor-alpha (TNF-alpha) were measured. Results: The plasma levels of CFH, IL-10 and TNF-alpha were higher in drug-naive MDD patients than control subjects. Compared to MDD patients without anhedonia, patients with anhedonia showed higher levels of CFH and IL-6. The stepwise regression analysis revealed that IL-10, TNF-alpha, as well as IL-10 x TNF-alpha were associated with depressive symptoms measured by HAMD-17 in drug-naive MDD patients, while only CFH levels were identified as a mediator factor for the severity of anhedonia in the patients. Conclusion: MDD patients with anhedonia showed different inflammatory characteristics compared to patients without anhedonia. Our results provide novel evidence suggesting that increased plasma CFH levels may be a potential biomarker of anhedonia of subtyping MDD.

Automated summary

The study revealed that patients with anhedonia in major depressive disorder exhibit different inflammatory characteristics compared to patients without anhedonia. Elevated plasma CFH levels may serve as a potential biomarker for anhedonia in subtyping MDD.