Peripheral inflammation is associated with impaired sadness recognition in euthymic bipolar patients

Area of Science:

• Neuroscience
• Psychiatry
• Immunology

Background:

• Inflammation negatively affects cognitive function in healthy individuals and psychiatric disorders like bipolar disorder (BD).
• Emotion recognition, a key aspect of social cognition, may be influenced by inflammation.
• The relationship between pro-inflammatory cytokines and emotion recognition in BD requires further investigation.

Purpose of the Study:

• To examine the association between pro-inflammatory cytokines and emotion recognition in euthymic BD patients and healthy controls (HCs).
• To identify predictive factors for sadness recognition accuracy in BD patients.

Main Methods:

• Recruited 44 euthymic BD patients and 40 HCs.
• Measured inflammatory markers: high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), and TNF-α.
• Assessed cognitive function (WCST, CPT) and emotion recognition (DANVA-2-TW).

Main Results:

• Tumor necrosis factor-alpha (TNF-α) was higher in euthymic BD patients compared to HCs.
• In BD patients, elevated TNF-α correlated with reduced sadness recognition accuracy.
• TNF-α independently predicted sadness recognition accuracy in euthymic BD patients, even after controlling for neurocognition.

Conclusions:

• Increased TNF-α, indicating heightened inflammation, independently predicts impaired sadness recognition in BD patients.
• This suggests a direct impact of TNF-α on sadness recognition.
• Chronic inflammation may increase vulnerability to depression in euthymic BD patients.