Table 1.
Socio-demographic and clinical characteristics of participants at baseline.
| Control group (N = 58) | MDD group (baseline, N = 80) | Significance | |
|---|---|---|---|
| Age (year, mean ± SD) | 45.5 ± 12.0 | 45.4 ± 12.1 |
t = 0.08 p = 0.93 |
| Gender (female/male) | 31/27 | 47/33 | X2 = 0.38 p = 0.53 |
| Educational level (low/high)a | 13/45 | 48/32 | X2 = 19.3 p < 0.001** |
| Age of onset (year, mean ± SD) | – | 36.1 ± 13.2 | – |
| Number of episodes (%) | |||
| First | – | 33.8 | – |
| Second | 32.4 | ||
| Third or higher | 33.8 | ||
| Early life stress event (% yes)b | 10.3 | 38.0 | X2 = 13.18 p < 0.001** |
| Antidepressant use (%) | |||
| None | 96.6 | 4 | – |
| SSRI | 1.7 | 41 | |
| SNRI | 0 | 34 | |
| Other (TCA, mirtazapine, bupropion) | 1.7 | 21 | |
| Depression severity (HDRS) | 0.6 ± 1.3 | 16.9 ± 5.0 | p < 0.001** |
| Positive affect (PANAS) | 36.3 ± 5.6 | 18.1 ± 5.8 | p < 0.001** |
| Negative affect (PANAS) | 14.7 ± 4.2 | 33.2 ± 8.7 | p < 0.001** |
| Anhedonia (SHAPS) | 19.2 ± 4.1 | 35.7 ± 7.6 | p < 0.001** |
| Neuroticism (NEO-FFI) | 3.4 ± 1.6 | 8.1 ± 1.3 | p < 0.001** |
P-values are derived from statistical analysis using independent sample t-test for continuous variables or Chi-Square test for categorical variables.
HDRS: Hamilton Rating Scale for Depression; PANAS: Positive and Negative Affect Scale; SHAPS: Snaith¬Hamilton Pleasure Scale; NEO-FFI: NEO-Five Factor Inventory Scale.
a
Low education = finished secondary school or less; High education = any additional education after secondary school.
b
Early life stress event: assessed by Structured Trauma Interview (STI).