Abstract
BACKGROUND: Schizophrenia (SCZ) is a severe psychiatric disorder characterized by cognitive dysfunction and persistent psychotic symptoms. Treatment refractory schizophrenia (TRS), resistant to conventional antipsychotics, presents significant challenges. Electroconvulsive therapy (ECT) is effective for TRS, but its biological mechanisms remain unclear. Biomarkers such as brain-derived neurotrophic factor (BDNF), interleukin-6 (IL-6), and cortisol, linked to neuroplasticity, immune modulation, and stress regulation, may help elucidate ECT's therapeutic effects. AIM: This study evaluated the impact of ECT on serum levels of BDNF, IL-6, and cortisol in TRS patients and explored the relationship between these biomarkers and symptom improvement. MATERIALS AND METHODS: A prospective study was conducted at a tertiary care hospital from 2018 to 2020. Thirty-five TRS patients (aged 18-60 years) underwent symptom severity assessments using the positive and negative syndrome scale (PANSS) pre- and post-ECT. Serum levels of BDNF, IL-6, and cortisol were measured using enzyme-linked immunosorbent assays (ELISA). ECT was administered bilaterally in 4-7 sessions per patient. Paired t-tests and Spearman's correlation were used for statistical analysis. RESULTS: ECT significantly reduced positive (P < 0.001), general (P < 0.001), and total PANSS scores (P < 0.001), with modest reductions in negative symptoms (P < 0.001). Serum IL-6 levels decreased significantly post-ECT (P = 0.018), while changes in BDNF (P = 0.198) and cortisol (P = 0.403) were not statistically significant. Increased BDNF levels positively correlated with reduced positive symptoms (P = 0.041), while decreased IL-6 levels correlated with symptom improvement (P = 0.045). CONCLUSION: ECT reduces symptom severity in TRS, with significant modulation of IL-6 and potential involvement of BDNF in positive symptom improvement. These findings highlight immune and neuroplastic pathways as mechanisms of ECT efficacy and suggest biomarkers for treatment response.