Pro-inflammatory markers and fatigue in patients with depression: A case-control study

Area of Science:

• Neuroscience
• Immunology
• Psychiatry

Background:

• Depression is frequently accompanied by fatigue.
• Inflammation is increasingly recognized as a factor in depression.
• The relationship between specific fatigue dimensions and inflammatory markers in depression requires further investigation.

Purpose of the Study:

• To investigate differences in fatigue dimensions and inflammation between depressed participants (PG) and healthy controls (HCG).
• To explore correlations between pro-inflammatory markers and depression/fatigue symptoms within each group.

Main Methods:

• Recruited 43 depressed participants (PG) and 51 healthy controls (HCG).
• Assessed Interleukin-6 (IL-6), Interleukin-1 beta (IL-1β), Tumor Necrosis Factor-alpha (TNF-α), Interferon-gamma (IFN-γ), and C-reactive protein (CRP) in blood samples.
• Utilized the Fatigue Impact Scale for Depression (FIS-D) and Beck Depression Inventory-Fast Screen (BDI-FS) for assessments.

Main Results:

• Depressed participants (PG) exhibited higher BDI-FS scores and significant differences in fatigue dimensions compared to HCG.
• A moderate group effect for pro-inflammatory markers was observed between PG and HCG, primarily driven by IL-6.
• Correlations between specific inflammatory markers (TNF-α, IL-6) and fatigue dimensions (cognitive, psychosocial, somatic) were identified within both groups, alongside psychological variable correlations.

Conclusions:

• Inflammation is present in both depression and fatigue.
• Distinct pro-inflammatory profiles correlate with depression and fatigue, indicating biological heterogeneity.
• These findings may inform targeted therapeutic strategies for depression and fatigue.