Table 4.
Characteristics of the clinical trials on prebiotics, probiotics, and synbiotics in major depressive disorder included in the systematic review.
| Authors | Study Design | Country | Population | Depression Definition | Mean Age (SD) | Sex (% F) |
|---|---|---|---|---|---|---|
| Akkasheh 2016 [70] | DB RCT | Iran | MDD (N = 40) | DSM-IV; HAMD-17 ≥ 15 |
Pro: 38.3 (12.1) Plb: 36.2 (8.2) |
ND |
| Bambling 2017 [71] | Open-label trial |
Australia | Resistant MDD (N = 12) |
MINI-V | Pro: 49.3 (10.9) | Pro: 66.7 |
| Romijn 2017 [72] | DB RCT | New Zealand | Low mood (N = 79) | QIDS-SR16 ≥ 11; DASS-42-D ≥ 14 |
Pro: 35.8 (14) Plb: 35.1 (14.5) |
Pro: 20 Plb: 23 |
| Ghorbani 2018 [73] | DB RCT | Iran | MDD (N = 40) | DSM-V | Syn: 34.45 Plb: 35.50 |
Syn: 70 Plb: 70 |
| Miyaoka 2018 [74] | Prospective open-label trial | Japan | TRD (N = 40) | DSM-IV-TR | Pro: 44.2 (15.6) Ctr: 41.9 (14.2) |
Pro: 52.0 Ctr: 52.0 |
| Chahwan 2019 [77] | TB RCT | Australia | Clinical and sub-clinical depression (N = 71) | MINI-IV | Pro: 36.65 (11.75) Plb: 35.49 (12.34) Ctr: 35.95 (11.74) |
Pro: 21 Plb: 28 Ctr: 15 |
| Kazemi 2019 [75] | DB RCT | Iran | MDD (N = 110) | ICD-10 | Pro: 36.2 Pre: 75.0 Plb: 66.7 |
Pro: 71.1 Pre: 75.0 Ctr: 66.7 |
| Rudzki 2019 [76] | DB RCT | Poland | MDD (N = 60) | DSM-IV-TR | Pro: 39.13 (9.96) Plb: 38.90 (12) |
Pro: 76.7 Plb: 66.7 |
| Heidarzadeh 2020 [79] | DB RCT | Iran | MDD (N = 78) | ICD-10 | Pro: 36.2 Pre: 75.0 Plb: 66.7 |
Pro: 71.1 Pre: 75.0 Plb: 66.7 |
| Reininghaus 2020 [80] | DB RCT | Austria | MDD (N = 82) | MINI-IV | Pro: 43.00 (14.31) Plb: 40.11 (11.45) |
Pro: 71.4 Plb: 81.8 |
| Reiter 2020 [81] | DB RCT | Austria | MDD (N = 61) | MINI-IV | Pro: 43.00 (14.31) Plb: 40.11 (11.45) |
Pro: 71.4 Plb: 81.8 |
| Saccarello 2020 [82] | DB RCT | Italy | MDD (N = 90) | ICD-10 | Pro: 48.6 (10.67) Plb: 47.5 (11.9) |
Pro: 84.4 Plb: 75 |
| Arifdjanova 2021 [87] | Open RCT | Russia | Mild-moderate depressive episode | ICD-10 | Pro: 32.9 (6.1) Plb: 33.1 (5.7) |
Pro and Plb: 62.2 |
| Browne 2021 [83] | DB pilot trial | Netherlands | Depressive sxs (N = 40) |
EPDS ≥ 10 | Pro: 29.65 (3.9) Plb: 31.7 (4) |
ND |
| Chen 2021 [84] | Open trial | Taiwan | MDD (N = 11) | DSM-V | Pro: 39.4 (12.0) | Pro: 72.7 |
| Vaghef-Mehrabany 2021 [78] | DB RCT | Iran | MDD (N = 62) | DSM-V | Pre: 37.45 Plb: 40.00 |
ND |
| Wallace 2021 [53] | Open pilot study | Canada | MDD (N = 10) | MINI-IV; MADRS ≥ 20 |
Pro: 25.2 (7.0) Plb: 40.00 |
Pro: 70 |
| Zhang 2021 [86] | DB RCT | China | MDD (N = 69) | DSM-V | Pro: 45.8 (12.3) Plb: 49.7 (9.6) |
Pro: 63.2 Plb: 84.5 |
| Tian 2022 [85] | DB RCT | China | MDD (N = 45) | HAMD-24 > 14 | Pro: 51.32 (16.11) Plb: 48.15 (13.96) |
Pro: 70.0 Plb: 64.0 |
Note. Abbreviations: CES-D, Center for Epidemiological Studies Depression Scale; Ctr, control; DASS-42-D, depression subscale of the Depression, Anxiety and Stress Scale; DB, double-blind; DSM-IV-TR, Diagnostic and Statistical Manual of Mental Disorders-Fourth Edition-Text Revision; DSM-IV, Diagnostic and Statistical Manual of Mental Disorders-Fourth Edition; DSM-V, Diagnostic and Statistical Manual of Mental Disorders-Fifth Edition; EPDS, Edinburgh Postnatal Depression Scale; HAM-D, Hamilton Depression Rating Scale; HAMD-17, Hamilton Depression Rating Scale-17; HAMD-24, Hamilton Depression Rating Scale-24; ICD-10, International Statistical Classification of Diseases and Related Health Problems-10; MADRS, Montgomery-Asberg Depression Rating Scale; MDD, major depressive disorder; MINI-IV, Mini-International Neuropsychiatric Interview for DSM-IV; MINI-V, Mini-International Neuropsychiatric Interview for DSM-V; ND, Not declared; Plb, placebo; Pre, prebiotic; Pro, probiotic; QIDS-SR16, Quick Inventory of Depressive Symptomatology; RCT, Randomized controlled trial; SB, single-blind; SSRI, Selective serotonin reuptake inhibitor; Sxs, symptoms; Syn, synbiotic; TB, triple-blind; TRD, treatment-resistant major depressive disorder.