Schizophrenia Disorders
Conditions
Keywords
Electroconvulsive teraphy, Schizophrenia, Rigth unilateral, Cognition, Efficacy
Brief summary
Electroconvulsive therapy (ECT) is an established treatment for medication-resistant schizophrenia. There is debate about the best method of electrode placement. Bitemporal (BT) placement is commonly used for schizophrenia, while right unilateral (RUL) placement in mood disorders is associated with fewer adverse effects on memory and language. This study compares the efficacy, safety and cognitive effects of BT-ECT versus RUL-ECT in hospitalized schizophrenia patients with acute psychosis. Main Question: Does RUL-ECT reduce psychotic symptoms with fewer cognitive effects versus BT-ECT in patients with severe schizophrenia? Hypothesis: RUL-ECT is as effective as BT-ECT in reducing psychotic symptoms with fewer cognitive effects. Methods: Randomized trial in patients with schizophrenia (confirmed by DSM 5 criteria) and severe symptoms (PANSS score ≥60). Patients were assigned to receive BT-ECT or RUL-ECT. Efficacy was measured by a ≥30% reduction in symptom severity on the PANSS scale and overall improvement measured with the Clinical Global Impression scale. Cognitive function was assessed with the Montreal Cognitive Assessment (MoCA) and Brief Assessment of Cognition in Schizophrenia (BACS) scales.
Detailed description
Study Design and Setting: Randomized experimental trial at Fray Bernardino Álvarez Psychiatric Hospital, Mexico City. Sample Size: Quota sampling. Eligibility Criteria: inpatients, spanish-speaking, ≥18 years old with DSM-5 schizophrenia diagnosis, PANSS total score ≥60, and treatment with 1-2 antipsychotics (including clozapine). Exclusions: ECT within 3 months, affective comorbidities, catatonia, pregnancy, anesthesia/ECT contraindications, or incomplete follow-up. Equipment and Technique: Pre-ECT evaluations included ECG, chest X-ray, blood tests, and assessments by internists/anesthesiologists. ECT was administered by a principal investigator (Emory University-certified) using a MECTA Corp spECTrum 5000Q device, 3x/week (excluding weekends). Electrode placement: bitemporal (BT) with brief pulses (≥0.5 ms) or right unilateral (RUL; D'Elia placement) with ultrabrief pulses (≤0.3 ms). Initial titration doses: 48 mC (BT) or 4.8 mC (RUL), doubled until adequate seizure (assessed via Clinical and Seizure Based Stimulation method). Maintenance doses: 2x threshold (BT) or 6x threshold (RUL), adjusted by 50% for poor-quality seizures. Premedication: atropine (1 mg IM), propofol (1 mg/kg IV), and succinylcholine (1 mg/kg IV). Intervention and Comparator: Active comparator: BT-ECT vs. RUL-ECT.(intervention) No placebo group due to institutional constraints. Randomization and Blinding: Block randomization (Microsoft Excel-generated) by an independent researcher. Allocation sequence concealed by an assistant and disclosed pre-treatment. Outcomes: Efficacy: ≥30% PANSS reduction; Safety: Adverse event frequency/severity/time to adverse event onset. Cognition: MoCA and BACS pre-/post-ECT (administered by neuropsychology-trained staff). Ethics: Conducted per WMA Declaration of Helsinki. Informed consent obtained from patients' legal guardians due to severe mental impairment in participants
Interventions
PROCEDUREBrief pulse Electroconvulsive therapy
Therapeutic seizure induction with pulse unidirectional electric charge through the temporal hemisferes, using brief pulses (≥0.5 ms).
PROCEDUREUltrabrief pulse electroconvulsive therapy
Therapeutic seizure induction with pulse unidirectional electric charge through the right hemisphere, using ultrabrief pulses (≤0.3 ms).
Sponsors
Hospital Psiquiátrico Fray Bernardino Álvarez
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Subject)
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
A) Inclusion Criteria: 1. Spanish-speaking. 2. any sex/gender. 3. Aged ≥18 years. 3\. Diagnosis of schizophrenia per DSM-5 criteria. 4. Baseline PANSS (Positive and Negative Syndrome Scale) total score ≥60. 5. Treatment with 1-2 antipsychotics (including clozapine). B)
Exclusion criteria
1. Received ECT (electroconvulsive therapy) within the previous 3 months. 2. Comorbid affective disorders (e.g., bipolar disorder, major depressive disorder). 3. Catatonia or catatonic syndrome. 4. Pregnancy 5. Contraindications to general anesthesia/ECT (i.e. uncontrolled cardiovascular disease or intracranial hypertension).
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Efficacy of electroconvulsive therapy technique | 48 hours after last ECT session | Treatment response is defined as a ≥20% reduction in the total score of the Positive and Negative Syndrome Scale (PANSS) after treatment. A dichotomous classification was applied (responders vs. non-responders) The PANSS assesses symptom severity through 30 items, each scored on a 1-7 scale, where: 1 = Absent (no symptom) and 7 = Extreme (severe symptom). Higher PANSS scores indicate greater symptom severity, meaning a lower score reflects a better clinical outcome. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Adverse effect incidence | Between two hours and 24 hours after the last ECT session | The incidence of side effects will be expressed as the percentage of subjects affected within each study group. |
| Time to adverse event onset measured in number of sessions | From the first session until 48 hours after last session | Time to adverse event onset is defined as the number of completed ECT sessions where the outcome is first documented. Count of sessions from Session 1 (baseline) to the session where the AE is first documented. |
| Cognitive changes measured by MoCA | 48 hours after last ECT session | Change in total Montreal Cognitive Assessment (MoCA) score at the end of treatment. Result will be analyzed as a continuous linear variable. MoCA evaluates 7 domains, with item-level binary scoring (0/1). Serial-7s allow up to 3 points (1 per correct subtraction). Total scores are interpreted against validated cutoffs. Cutoff: \<26/30 suggests impairment (adjusted for education ≤12 years: +1 point). Total Score: 0-30 (higher = better cognition). |
| Cognitive changes measured by BACS | 48 hours after last ECT session | Change in Brief Assessment of Cognition in Schizophrenia (BACS) total score post-treatment. BACS is a neuropsychological battery designed to assess cognitive impairment in individuals with schizophrenia. Consists of 6 subtests, each assessing a specific cognitive domain. Raw scores are converted to standardized z-scores (mean = 0, SD = 1) based on normative data. Higher scores = Better cognitive performance. |
Countries
Mexico
Outcome results
None listed