Table 1.
Demographic and clinical characteristics of participants in the 15 included studies
| Study | Number (female) | Age at study, y | Age of onset, y | Illness duration, y | Mean number of episodes | Statistic of cortical thickness (correction) | Score of severity (scale type) | Medication status | Scanner field strength (Tesla) | Voxel size (mm3) | ||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| MDD | HCs | P value for sex | MDD | HCs | P value for age | |||||||||
| Han et al. [19] | 20 (15) | 22 (15) | 0.63 | 42.7 | 43.7 | 0.81 | NA | 0.4 | 1.8 | P < 0.05 (MCS) | 19 (HDRS-17) | All naive | 3.0 | 1.0 × 1.0 × 1.0 |
| Kakeda et al. [13] | 40 (20) | 47 (13) | 0.05 | 46.6 | 40.7 | 0.06 | NA | 0.5 | 1.0 | P < 0.05 (MCS) | 22 (HDRS-17) | All naive | 3.0 | 0.9 × 0.9 × 1.2 |
| Lan et al. [30] | 56 (32) | 54 (26) | 0.65 | 36.9 | 31.8 | 0.06 | 23.4 | 13.6 | NA | P < 0.05 (MCS) | 24 (HDRS-17) | All Untreated > 2 weeks | 3.0 | 1.0 × 1.0 × 1.0 |
| Liu et al. [28] | 30 (13) | 41 (13) | 0.32 | 44.9 | 41.2 | 0.22 | NA | NA | 1.0 | P < 0.05 (MCS) | 21 (HDRS-17) | All naive | 3.0 | 0.9 × 0.9 × 1.2 |
| Na et al. [29] | 45 (34) | 72 (51) | 0.31 | 41.6 | 40.7 | 0.35 | NA | 2.5 | 1.8 | P < 0.05 (MCS) | 20 (HDRS-17) | All naive | 3.0 | 1.0 × 1.0 × 1.0 |
| Niu et al. [16] | 36 (19) | 30 (13) | 0.68 | 29.1 | 27.8 | 0.78 | 24.9 | 3.5 | 1.8 | P < 0.05 (MCS) | 27 (HDRS-24) | Untreated > 6 months (n = 17) Naive (n = 19) | 3.0 | NA |
| Peng et al. [9] | 16 (9) | 16 (9) | 1.00 | 34.4 | 33.9 | 0.77 | 33.3 | 0.2 | 1.0 | P < 0.05 (FDR) | 31 (HDRS-24) | All naive | 3.0 | 0.9375 × 0.9375 × 1.0000 |
| Qiu et al. [7] | 46 (33) | 46 (33) | 1.00 | 34.9 | 35.4 | 0.58 | NA | 0.4 | 1.0 | P < 0.05 (FDR) | 23 (HDRS-17) | All naive | 3.0 | NA |
| Späti et al. [14] | 21 (10) | 35 (20) | 0.49 | 36.6 | 32.7 | > 0.2 | NA | NA | 6.0 | P < 0.05 (MCS) | 26 (BDI) | Untreated > 6 weeks (n = 5) Naive (n = 16) | 3.0 | 0.94 × 0.94 × 1.00 |
| Taylor et al. [18] | 74 (52) | 91 (56) | 0.24 | 36.4 | 29.9 | NAa | NA | 5.9 | 3.1 | P < 0.05 (MCS)b | 24 (MADRS) | All Untreated > 1 month | 3.0 | 0.9 × 0.9 × 1.2 |
| van et al. [12] | 40 (27) | 31 (19) | 0.95 | 35.0 | 34.7 | 0.90 | 33.6 | 1.2 | 1.0 | P < 0.05 (FDR) | 13 (HDRS-17) | Untreated (n = 20)c/naive (n = 20) | 1.5 | 1.0 × 1.0 × 1.0 |
| van et al. [10] | 23 (15) | 22 (14) | 0.91 | 50.7 | 50.8 | 0.98 | 40.8 | NA | 2.8 | P < 0.05 (MCS) | 22 (HDRS-17) | All Untreated > 1 week | 1.5 | 1.0 × 1.0 × 1.0 |
| Wagner et al. [17] | 30 (25) | 30 (25) | 1.00 | 37.6 | 35.1 | NAd | 31.6 | 6.0 | 1.3 | P < 0.05 (MCS) | 25 (HDRS-21) | Untreated (n = 23)c/naive (n = 7) | 1.5 | 1.0 × 1.0 × 1.0 |
| Yang et al. [15] | 27 (13) | 27 (13) | 1.00 | 28.6 | 28.7 | 0.07 | 27.8 | 0.8 | 1.0 | P < 0.001 (Uncorr) | 28 (HDRS-24) | All naive | 3.0 | 1.0 × 1.0 × 1.0 |
| Zorlu et al. [11] | 25 (15) | 22 (14) | 0.71 | 36.7 | 38.5 | 0.45 | 30.6 | NA | 1.7 | P < 0.05 (MCS) | 26 (HDRS-17) | All Untreated > 2 months | 1.5 | 1.0 × 1.0 × 1.0 |
BDI Beck Depression Inventory, FDR false discovery rate, HCs healthy controls, HDRS-17/21/24 17/21/24-item Hamilton Depression Rating Scale, MADRS Montgomery–Asberg Depression Rating Scale, MCS Monte Carlo simulations, MDD major depression disorder, NA not available, Uncorr uncorrected, y year
aAlthough this study did not demonstrate the result of age compared between all the patients (both without and with thoughts of death) and controls, age was controlled as a covariate for all the group comparisons of cortical thickness
bThe author confirmed that there were no statistically significant differences in cortical thickness between the control group and the entire MDD group by email
cThese studies did not report the period of the untreated state
dThis study did not report the P values of mean age, but they stated no differences in age between patients with MDD and HCs