Table 1 Overview of current literature on baseline BDNF and ECT outcome
From: Brain-derived neurotrophic factor as a possible predictor of electroconvulsive therapy outcome
Paper | N, gender, agea (years) | Diagnosis and severity of depressiona | Blood sampling and overall BDNF levels | ECT characteristics | Psychotropic medication | Outcome measure | Main result (BDNF levels and p-value) |
|---|---|---|---|---|---|---|---|
Bocchio-Chiavetto et al.50b,c | N = 23 ♀ 69.6% 53.0 (±17.4) | TR MDD (100% UP) 56.5% PS MADRS: 34.21 (±7.91) | In morning after overnight fast Storage −80 °C ELISA quantikine kit RD system Serum BDNFa 27.6 (±9.1) ng/ml | 3×/week, BL BP No. of sessionsa: 7 (±2.0) | Continued, except in one participant | Remission (<9 on MADRS at two consecutive assessments), remission rate: 33.3% | Remitters: 27.1 ± 9.3 Non-remitters: 31.2 ± 8.4 p = 0.44 |
Marano et al.55b,c | N = 15 ♀26.7 % 50d | MDD (66.7% UP, 33.3 BiP) 40.0% PS HRSD-21d: 30.0 (±9.0) | Before ECT, Storage −80 °C ChemiKine BDNF sandwich ELISA kit Plasm BDNFd 84.9 (±4.65) pg/ml | 3×/week, BL or BF, BP No. of sessionsd: 7 | Continued | Response (−50% on HRSD-21), response rate: 86.7% | Responders: 83.1 ± 63.0 Non-responders: 119.5 ± 33.1 p = ND |
Okamoto et al.52b | N = 18 ♀ 50% 60.6 (±14.1) | MDD or BiP, 27.7% PS HRSD-17: 23.1 (±4.5) | 7.00 AM, after overnight fast Storage −80 °C BDNF Emax Immunoassay Kit Serum BDNFa 11.0 (±11.2) ng/ml | 3×/week, BL BP No. of sessions: 12 | Continued | Response (−50% on HRSD-17), response rate: 66.7% Remission (<7 on HRSD-17), remission rate: 33.3% | Responders: 7.9 ± 9.9 Non-responders: 11.5 ± 11.0 p = ND, but it was reported to be not significant. |
Fernandes et al.60b | N = 15 ♀ 66.7% 52.7 (±15.9) | TR MDD (73.3% UP, 26.7% BiP), 53.9% PS HRSD: 24.15 (±6.32) | 1 day before ECT Storage −80 °C Sandwich ELISA, total protein measured by Lowry’s method Serum BDNFd 0.3 (IQR 0.1) pg | 3×/week, UL BP No. of sessionsa: 11.2 (±1.4) | Continued | Response (−50% on HRSD), response rate: 73.3% Remission (<7 on HRSD), remission rate: 33.3% | BDNF levels and p value: ND No differences between ECT outcome groups. |
Piccinni et al.59b | N = 18 ♀ 50% 44.9 (±17.0) | MDD (11% UP, 89%vBP), 44% PS HRSD-21: 26.4 (±6.0) | In morning after overnight fast Storage −20 °C ELISA Plasm BDNFb 2.1 (±1.2) ng/ml | 2×/week, BL BP No. of sessionsa: 8.3 (±1.2) | Continued, except mood stabilizers | Remission (<10 on HRSD-21 at two consecutive assessments), remission rate: 44.4% | Remitters: 2.9 ± 1.3 Non-remitters: 1.5 ± 0.5 p = 0.02 |
Hu et al.54c | N = 28 ♀ 82.1% 41.0 (±14.8) | MDD HRSD-17: 31.39 (±4.65) | 7:30 and 8:30 AM, 1 day before ECT Storage −20 °C Promega Enzyme-linked immunosorbent assay kit Serum BDNFa: 5.66 (±2.07) ng/ml | 3×/week, BL | Discontinued | Response (−50% on HRSD-17), response rate: 85.7% | Responders:5.5 ± 1.9 Non-responders: 6.5 ± 3.4 p = ND |
Gedge et al.58c | N = 11 ♀ 63.6% 46.5 | MDD HRSD-17: 23.73 (±1.43) | 7 days before ECT Storage −20 °C Sandwich ELISA Emax Immuno-AssaySystem Serum BDNFa: 9.95 (±1.94) ng/ml | 3×/week Administered as per hospital protocol No. of sessions: 12 | Continued | Response (−50% on HRSD-17), response rate: 45.5% | Responders:13.3 ± 6.7 Non-responders: 7.2 ± 5.2 p = ND |
Stelzhammer et al.56c | N = 7 ♀ 71.4% 52.9 (±8.8) | TR MDD HRSD: 26.9 (±6.9) | Immediately before first ECT session Storage −80 °C Serum BDNFa: ND ng/ml | 3×/week, BP Administered as per hospital protocol No. of sessions: 12 | Discontinued, start with AD after 6 ECT sessions | Response (−50% on HRSD), response rate: 42.9% | Responders:20.4 ± 13.5 Non-responders: 22.7 ± 7.0 p = ND |
Kleimann et al.51b,c | N = 11 ♀ 45.5% 47 (±16.5) | TR MDD, 73% PS MADRS: 34 (±8.3) | 8–10 AM after overnight fast Storage −80 °C DuoSet enzyme-linked immunesorbent assay Development System Serum BDNF: ND pg/ml | 3×/week, during 3.5 weeks Technique: as common practice in the facility | Continued | Response (−50% on MADRS), response rate: 54.5% Remission (<13 on MADRS), remission rate: 36.4% | Responders: 541.2 ± 294.9 Non-responders: 721.8 ± 364.1 p = 0.37 |
Freire et al.57b | N = 21 ♀ 90.5% 48.75 (±15.4) | DD (52.4% UP, 42.9% BiP), 47.6% PS HRSD-17: 26.04 (±6.62) | At admission Storage −80 °C ELISA, Milipore kit Serum BDNF: ND | 3×/week, UL high dose, BP No. of sessionsa: 8.8 (2.3) | Continued | Remission (<8 on HRSD-17), remission rate: 52.4% | BDNF levels: ND, but BDNF was higher in remitters than in non-remitters. p = 0.03 |
Ryan et al.53e | N = 61 ♀ 55.7% 52.7 (±15.4) | MDD (75.4% UP, 24.6% BiP), 24.6% PS HRSD-24: 31.2 (6.8) | 7.30–9.30 AM, after overnight fast Storage −80 °C DuoSet® ELISA kit Plasm BDNFa: 1.09 (±0.19) log10 ng/ml | 2×/week, 50.8% received moderate dose BL, 49.3% received high dose UL No. of sessionsa: 8.2 (2.6) | Continued | Response (−60% on HRSD-24 and a final score of ≤16 on HRSD-24), response rate: 54.1% Remission (−60% on HRSD-24 and a score of ≤10 for 2 weeks on HRSD-24), remission rate: 41.0% | Responders: 1.08 ± 0.2 Non-responders: 1.11 ± 0.2 p = 0.87 Remitters: 1.07 ± 0.2 Non-remitters: 1.11 ± 0.2 p = 0.1 |
Van Zutphen, 2019b | N = 94 ♀ 68.1% 73.3 (±8.1) | MDD, 51.1% PS MADRSd: 34.0 (±12.0) | 7.30 and 9.30 AM after overnight fast Storage −85 °C Emax Immuno Assay System Serum BDNFa: 18.1 (±6.6) ng/ml | 2×/week, UL or BL BP No. of sessionsd: 11 (6.3) | Continued in 38.3% | Response (−50% on MADRS), response rate: 81.9% Remission (<10 on MADRS), remission rate: 69.1% | Responders: 17.6 ± 6.7 Non-responders: 20.6 ± 5.6 p = 0.08 Remitters: 17.1 ± 6.8 Non-remitters: 20.4 ± 5.6 p = 0.02 |
