Right Temporal Delta Power in Quantitative Electroencephalogram as Predictor of Early Response to Clozapine in Treatment-Resistant Schizophrenia

Abstract

Background

Schizophrenia affects millions globally, with up to 30% showing resistance to standard antipsychotics. Clozapine is effective for treatment resistant schizophrenia (TRS), but its use is often delayed. This study explores Quantitative electroencephalogram (QEEG) as a tool to predict clozapine response in Indian TRS patients, aiming to support early, personalized treatment.

Aim

This study aims to predict treatment response to clozapine in TRS patients using quantitative electroencephalogram (QEEG) by assessing and comparing baseline and 6 weeks QEEG patterns and their changes in responders versus non-responders.

Methods

39 clozapine-naïve TRS patients were recruited at tertiary care hospital in North India and assessed using BPRS, GASS-C and EEG at baseline, 3 weeks and 6 weeks. EEG data were processed and analyzed for frequency band power to compare responders (≥20% BPRS improvement) and non-responders.

Results

Of the 39 patients included, 36 completed the study, with 67% classified as responders and 33% as non-responders. Responders showed significantly higher right temporal delta power at 3 and 6 weeks, with ROC analysis at 6 weeks yielding an Area under curve of 0.757 (P = .014). Statistically significant increases in delta and theta power were observed in responders.

Conclusions

Increased right temporal delta power was seen in responders, but changes were insufficient to reliably predict outcomes.