Serum Neurofilament Polypeptide Level in Patients with Bipolar Disorder and its Effect on Cognitive Functioning

Area of Science:

• Neuroscience
• Biomarkers
• Psychiatry

Background:

• Serum neurofilaments are potential indicators of neurodegeneration in bipolar disorder (BD).
• This study investigates neurofilament light (NF-L), medium (NF-M), and heavy (NF-H) chain levels across BD phases.

Purpose of the Study:

• To evaluate serum NF-L, NF-M, and NF-H levels in manic, depressive, and euthymic phases of BD.
• To explore the relationship between these neurofilament levels and neuropsychological functions using the Central Nervous System Vital Signs (CNSVS) test battery.

Main Methods:

• Inclusion of BD patients (DSM-5 diagnosed) and healthy controls, aged 18-50.
• Assessment using sociodemographic-clinical data forms, clinical scales, and CNSVS tests.
• Quantification of serum NF-L, NF-M, and NF-H via ELISA.

Main Results:

• Significant differences in mean NF-L, NF-M, and NF-H levels were observed between BD patients and controls (p < 0.001).
• In BD patients, elevated NF-M and NF-H levels negatively correlated with cognitive domains including NCI, composite memory, verbal/visual memory, cognitive flexibility, executive functions, and psychomotor speed.

Conclusions:

• Elevated serum neurofilament polypeptides across all BD stages suggest inflammatory-mediated axonal damage and potential biomarkers for neurodegeneration in BD.
• The CNSVS test battery is crucial for identifying neurocognitive deficits in BD.
• The negative correlation between serum NF-M/NF-H and cognitive performance highlights their association with neurodegeneration-related cognitive decline.