Table 2.
Studies published in English included for systematic review
| Author/ Country | Methodology | Subject characteristics | Indication for ECT | ECT technique | Cognitive measurements | Assessment schedule | Cognitive outcome | Risk of bias | GRADE rating |
|---|---|---|---|---|---|---|---|---|---|
| Chatterjee and Mohammed [11] (1980)/ India | Non-ran-domized, single-blind trial | n = 120, age range 16−50 years | 10 Major de-pression, 30 Schizophrenia in each treatment group | 1. Bitemporal 2. Unilateral non-dominant hemisphere 3. Unilateral dominant hemisphere Fixed dose, unknown pulse-width |
7 subtests from Indian version of Boston Memory Scale 1. Digit forward 2. Digit backward 3. Personal data (remote) 4. Personal data (recent 5. Common knowledge 6. Counting 20 to 1 7. Paired associates |
1. Pre-ECT 2. 3 weeks after treatment completion |
Within-group comparison showed significant improvement for group 2 only Schizophrenia memory score change 6.57 ± 13.44 Depression mean memory score change 4.50 ± 5.66 Between-group comparison showed no significant difference overall Between-group comparison showed significant improvement in immediate auditory verbal recall (mean change 0.88 ± 1.88) and memory dependent learning (mean change 2.19 ± 5.46) for group 2 |
High (non-ran-domized, rater-bias) | Low |
| Bagadia et al. [10] (1981)/ India | Double-blind controlled | n = 40, age range 18−65 years | 20 Depression, 20 Schizophrenia | 1. Bitemporal with placebo, fixed dose, pulse-width unknown (n = 20, 10 depressed and 12 schizophrenic) 2. Simulated ECT with imipramine for Depression or chlorpromazine for Schizophrenia (n = 20, 10 depressed and 8 schizophrenic) |
1. Koh’s Block Design Test 2. Picture Recognition Test 3. Bender Gestalt Test 4. Arithmetic 5. Immediate memory (digits) 6. Sentence Repetition 7. Remote memory 8. Recent memory |
1. Pre-ECT 2. 48 hours after treatment completion |
No significant change in cognitive test scores in both groups Significant improvement in Koh’s Block Design Test regardless of ECT when analysed by diagnosis group Depression: ECT with placebo Mean percent change 52.22 ± 50.39, p < 0.01 Depression: simulated ECT with imipramine Mean percent change 44.08 ± 48.43, p < 0.05 Schizophrenia: ECT with placebo Mean percent change 38.5 ± 33.2, p < 0.05 Schizophrenia: simulated ECT with chlorpromazine Mean percent change 20.1 ± 15.8, p < 0.05 |
High (not randomized) | Low |
| Bagadia et al. [21] (1988)/ India | Double-blind, randomized trial | n = 40, age range 18−65 years | Schizophrenia | 1.Bitemporal (n = 20) 2.Right unilateral (n = 20) Fixed dose, pulse-width unknown, first 3 sessions in 2-day intervals, next 3 at 4-day intervals |
Specially developed cognitive battery to assess learning, unaided recall, recognition and confabulation | 1. Pre-ECT 2. After 3 sessions 3. After 6 sessions |
Specific score not reported. Authors reported memory improvement in 40% of sample and impairment in 30% of sample, similar rates in both treatment groups |
High (randomiza-tion, alloca-tion, rater- blinding not mentioned) | Very low |
| Fujita et al. [22] (2006)/Japan | Retrospective naturalistic cohort | n = 18, mean age 49.8 ± 9.9 years | Major depression, Bipolar disorder (I or II) | 6−12 sessions of: 1.Bitemporal sine wave at fixed-dose with stepwise increments until seizure induced, mean of 9.9 ± 2.8 sessions 2.Bitemporal pulse-wave at aged-based dose with stepwise increments until seizure induced, mean of 11.0 ± 2.0 sessions |
1. MMSE 2. WMS-Revised 3. TMT A and B 4. Stroop Test 5. Verbal and Letter Fluency 6. Digit Symbol 7. Dual task |
1. 3−14 days pre-ECT 2. 3−14 days after treatment completion (mean 8.2 SD 3.5 days) |
No significant change in pre- and post-ECT MMSE and WMS scores. Significant improvement in Visual memory (57.9 ± 5.0 vs. 61.6 ± 5.1) and General Memory (113.7 ± 19.9 vs. 127.7 ± 25.3) for the pulse wave group. Impaired attention/executive function for the sine wave ECT group, (errors on Stroop Test 0.9 ± 0.6 vs. 2.3 ± 1.1 and Dual Task 88.5 ± 4.3 vs. 78.9 ± 7.6). Attention/Executive function scores improved for the pulse-wave group (Dual Task 77.2 ± 11.1 vs. 88.2 ± 7.3) The between-group difference in Dual Task performance was significant |
High (no controls) | Very low |
| Kunigiri et al. [23] (2007)/ India | Observational | n = 15, mean age 31.6 ± 6.5 years | Major depression with melancholia | 1.Bitemporal (n = 10) 2.Right unilateral (n = 5) Suprathreshold dosing, pulse-width unknown, 3 times per week |
1. Orientation Battery Test (OBT) 2. TMT A 3. Verbal Paired Associates from WMS 4. Verbal Learning Test 5. Passage Test 6. Benton Visual Retention Test |
1. Within 48 hours before first ECT 2. After 20 mins, 50 mins, 2 hours and 8 hours after the second and fifth sessions for the Orientation Battery Test and TMT 3. 8 hours after second and fifth sessions for memory tests |
Orientation and TMT scores declined at 20 mins then recovered by 8 hours post-ECT. After second session: OBT = 12 ± 0.0 vs. 6.6 ± 2.7 vs. 9.6 ± 1.6 vs. 10.8 ± 1.4 vs. 11.8 ± 0.4 TMT = 66.8 ± 27.3 vs. 139.6 ± 78.5 vs. 92.2 ± 63.9 vs. 63.9 ± 18.9 vs. 61.9 ± 20.3 After fifth session: OBT = 12 ± 0.0 vs. 4.9 ± 3.0 vs. 9.3 ± 2.0 vs. 10.3 ± 2.6 vs. 11.7 ± 0.6 TMT = 66.8 ± 27.3 vs. 135.1 ± 109.4 vs. 98.1 ± 71.6 vs. 74.8 ± 43.3 vs. 60.8 ± 19.8 Significant decline in all memory scores Verbal Paired Associates 9.1 (0.9) vs. 5.9 (1.4) vs. 5.3 (1.8) Verbal Learning 9.8 ± 1.0 vs. 6.2 ± 2.6 vs. 4.3 ± 1.6 Passage Test 14.9 ± 1.7 vs. 15.7 ± 3.3 vs. 9.6 ± 3.5 BVRT 8.8 ± 0.8 vs. 8.3 ± 0.8 vs. 7.7 ± 1.5 |
High (no controls) | Very low |
| Prakash et al. [13] (2015)/ India | Observational | n = 40, mean age 34.6 ± 3.7 years |
Depression, Non-affective psychotic disorders |
Bitemporal, brief pulse, dosing and pulse-width unknown, twice weekly | TMT and B | 1. Pre-ECT 2. After treatment completion 3. 4 weeks after treatment completion |
Significant improvement by 4 weeks after ECT TMT A: 22.20 ± 3.63 vs. 19.85 ± 2.91 vs. 17.52 ± 3.23 TMT B: 50.75 ± 6.84 vs. 46.62 ± 6.33 vs. 45.95 ± 6.53 |
High (no controls) | Very low |
| Tor et al. [15] (2017)/ Singapore | Retrospective naturalistic cohort | n = 48, mean age 43.74 ± 10.82 years | Schizophrenia | 1. Bitemporal (n = 17) age-based dosing, 0.5 ms pulse-width, mean 9.5 (3.4) sessions 2. Right unilateral (n = 10) stimulus titration, 0.5 ms pulse-width, mean 8.0 ± 3.3 sessions 3. Bitemporal (n = 10) stimulus titration, 0.5 ms pulse-width mean 11.3 ± 1.9 sessions 4. Bifrontal (n = 11) stimulus titration, 1.0 ms pulse-width, mean 11.6 ± 3.8 sessions |
Montreal Cognitive Assessment (MoCA) total score and score of delayed recall item | 1. 1−2 days pre-ECT 2. 1−2 days after treatment completion |
Group 1 showed significant decline in delayed recall. 1.88 ± 1.93 vs. 0.59 ± 1.12 Group 3 showed significant improvement in total score. 16.3 ± 11.0 vs. 24.0 ± 5.0 General significant overall improvement in total MoCA score with no significant between group differences. 16.8 ± 9.1 vs. 20.7 ± 6.0 |
High (no controls) | Very low |
Values are presented as mean ± standard deviation.
ECT, electroconvulsive therapy; GRADE, Grading of Recommendations, Assessment, Development and Evaluation; MMSE, Mini-Mental State Exam; WMS, Wechsler Memory Scale; TMT, Trail Making Tests; SD, standard deviation.