Effects of modifying the pulse width on cognitive side effects with electroconvulsive therapy for schizophrenia

Background: The majority of studies have shown substantially reduced cognitive impairment with ultra-brief pulse (UBP) electroconvulsive therapy (ECT) compared to brief pulse (BP) ECT, though the results remain inconclusive. Methods: This study employed a randomized, double-blind, controlled trial design. A total of 114 patients with schizophrenia (SCZ) were enrolled and received BP ECT (63 participants) or UBP ECT (51 participants). Cognitive function was assessed before and after treatment, with peripheral blood biomarkers and hippocampal magnetic resonance spectroscopy (MRS) data collected concurrently. Results: No significant baseline differences in demographic or clinical characteristics were observed between the two groups. After the end of ECT sessions, the UBP group and BP group respectively showed advantages in the Trail Making Test (TMT) and Hopkins Verbal Learning Test (HVLT). No between-group differences reached statistical significance in other cognitive tests. The homocysteine, prolactin, inducible nitric oxide synthase and left hippocampal myoinositol (MI) levels were significantly elevated in the UBP group than those in the BP group. Multiple linear regression analysis indicated that right hippocampal MI levels were positively correlated with TMT scores. Conclusion: There are no significant differences in efficacy between UBP ECT at high-dosage and BP ECT, and further research is required to determine whether this modality can reduce cognitive impairment after treatment. Clinical trial registration: https://www.chictr.org.cn/showproj.html?proj=243964, registration number: ChiCTR2400091601.