Treatment-resistant depression and peripheral C-reactive protein

Area of Science:

• Neuroscience
• Psychiatry
• Immunology

Background:

• C-reactive protein (CRP) is a potential biomarker for major depressive disorder (MDD).
• Understanding the relationship between peripheral CRP levels and diverse MDD clinical phenotypes is crucial.
• Investigating CRP's role in MDD can offer insights into disease heterogeneity.

Purpose of the Study:

• To explore C-reactive protein (CRP) levels in patients with major depressive disorder (MDD).
• To investigate the associations between CRP and specific clinical phenotypes within MDD.

Main Methods:

• Recruited 102 treatment-resistant MDD patients, 48 treatment-responsive MDD patients, 48 untreated depressed patients, and 54 healthy volunteers.
• Measured high-sensitivity CRP, BMI, depression, anxiety, and childhood trauma using questionnaires.
• Employed partial least squares (PLS) analysis to examine CRP's relationship with clinical phenotypes.

Main Results:

• BMI-corrected CRP was significantly elevated in treatment-resistant MDD patients compared to healthy controls (P = 0.007).
• PLS analysis revealed that vegetative depressive symptoms, BMI, state anxiety, and childhood adversity were strongly associated with CRP levels.
• These factors accounted for substantial variation in both clinical measures and CRP levels.

Conclusions:

• CRP is elevated in MDD patients, with higher levels in treatment-resistant individuals.
• Elevated CRP is associated with childhood adversity, specific depressive symptoms, and anxiety.
• Stratifying MDD patients by CRP levels may identify a subgroup potentially responsive to anti-inflammatory therapies.