Auditory P300 Potentials as State Biomarkers for Mild-to-Moderate Depression in Spinocerebellar Ataxia Type 2

Area of Science:

• Neuroscience
• Clinical Neurology
• Psychiatry

Background:

• Depression frequently co-occurs with spinocerebellar ataxia type 2 (SCA2).
• P300 event-related potentials are sensitive to cognitive changes but their role in SCA2 depression is unexplored.
• Identifying reliable biomarkers for depression in SCA2 is crucial for effective management.

Purpose of the Study:

• To investigate auditory P300 potentials as biomarkers for depression in SCA2 patients.
• To analyze P300 latency and amplitude in relation to depression severity and ataxia.
• To assess the potential of P300 as a diagnostic and therapeutic target indicator.

Main Methods:

• Auditory P300 oddball paradigms were used in 20 SCA2 patients and controls.
• Participants were stratified into depressed and non-depressed groups using the Beck Depression Inventory-II (BDI-II).
• P300 latency and amplitude were analyzed, alongside ataxia severity (SARA).

Main Results:

• Significant main effects of SCA2 and depression status on P300 latency and amplitude were found.
• SCA2 patients exhibited prolonged P300 latency and reduced amplitude compared to controls.
• Depressed individuals showed significantly altered P300 measures compared to non-depressed individuals within both cohorts.
• P300 alterations correlated with depression scores (BDI-II) but not ataxia severity (SARA).

Conclusions:

• Auditory P300 latency and amplitude function as state-dependent biomarkers for depression in SCA2.
• These P300 measures are independent of motor progression in SCA2.
• P300 potentials could serve as secondary endpoints in clinical trials for SCA2, facilitating precision medicine for affective symptoms.