The relationship between event-related potential components and suicide risk in major depressive disorder.

BACKGROUND: Suicide is a serious global issue, with major depressive disorder (MDD) being a significant risk factor for suicidal thoughts and behaviors. There is an urgent need to determine whether event-related potential components (ERPs) could be used as an indicator to assess suicidal risk. METHODS: From 2020 to 2023, 258 participants in total were recruited into the study. All participants were divided into four groups: MDD patients at high (n = 66), moderate (n = 66), and low risk (n = 56) of suicide, and healthy controls (HCs)(n = 70). Each participant provided socio-demographic information and underwent evaluations using clinical psychological scales such as 7-item Generalized Anxiety Disorder (GAD-7), Health Questionnaire-9 items (PHQ-9), and Nurses' Global Assessment of Suicide Risk (NGASR). The auditory brainstem response test and ERP examination were performed for all subjects. RESULTS: Our study found that the amplitude of P2-P3 and N2-P3 was significantly reduced in MDD patients at moderate and high risk of suicide, and these were negatively correlated with NGASR total score (all P < 0.05). Point B latency was positively correlated with NGASR total score (P < 0.05). Patients with MDD patients at low risk for suicide had a lower A-B amplitude compared to HCs (P < 0.05). No differences were found in MMN or P50 components between the four groups (all P > 0.05). CONCLUSIONS: MDD patients at higher risk of suicide exhibited severe impairment of cognitive function. ERP indices, such as the amplitude of P2-P3 and N2-P3, could be associated with the risk of suicide in MDD patients.

The differences of event-related potential components in patients with comorbid depression and anxiety, depression, or anxiety alone.

BACKGROUND: There was a high comorbidity rate of major depressive disorder (MDD) and generalized anxiety disorder (GAD), showing a poor prognosis and significant detrimental impact on functioning. The study aimed to find whether patients with comorbid GAD and MDD had some differences in cognitive functions from patients with MDD or GAD alone. METHODS: 360 adult patients were enrolled from inpatient department of psychiatry from 2020 to 2022. They were divided into three groups with 120 patients for each group: MDD, GAD, and MDD + GAD. All the patients completed psychological evaluation scales including patient health questionnaire-9 (PHQ-9) and 7-item generalized anxiety disorder (GAD-7). All the patients underwent examinations of auditory brainstem response and event-related potentials (ERPs). RESULTS: In MDD + GAD group, P3b latency was significantly longer than patients with MDD alone, and P300 reaction time was positively correlated with total score of GAD-7 and PHQ-9, and PHQ-9 total score was also significantly positively correlated with P2-P3b amplitude (all p < 0.05). In addition, MDD patients had significantly longer P300 reaction time and lower P2-P3b amplitude than the GAD group (p < 0.05). LIMITATIONS: It was a single-center and cross-sectional study, and we used self-report scales as assessment tools. CONCLUSIONS: Patients with MDD and GAD comorbidity might have a worse cognitive function than MDD patients, and the severity of cognitive impairments was positively correlated with the severity of anxiety and depression symptoms.