Table 1.
Demographic and clinical characteristics by group.
| Characteristic | HC (n = 16) |
Dep/SI− (n = 13) |
Dep/SI+ (n = 11) |
p |
|---|---|---|---|---|
| Age at time of 1H-MRS scan (years), mean ± SD | 16.90 ± 1.92 | 16.70 ± 2.08 | 16.26 ± 1.87 | 0.708a |
| Sex | 0.783a | |||
| Female, n (%) | 11 (68.75%) | 8 (61.54%) | 6 (54.55%) | |
| Male, n (%) | 5 (31.25%) | 5 (38.46%) | 5 (45.45%) | |
| Family history | ||||
| Any psychiatric illness, n (%) | 7 (50.00%)b | 13 (100%) | 11 (100%) | <0.001a |
| Mood disorder, n (%) | 7 (50.00%)b | 13 (100%) | 10 (90.91%) | 0.003a |
| Attempted or completed suicide, n (%) | 0 (0%)b | 5 (41.67%)c | 7 (63.64%) | <0.001a |
| Depression severity: CDRS-R | ||||
| Total score, mean ± SD | 18.50 ± 1.41 | 48.69 ± 7.93 | 57.64 ± 9.77 | 0.021d |
| Adjusted total score (without SI, morbid ideation items), mean ± SD | 16.50 ± 1.41 | 45.23 ± 7.24 | 49.36 ± 9.00 | 0.225d |
| Current psychotropic medication, n (%) | 0 (0%) | 4 (30.77%) | 5 (45.45%) | 0.675d |
| Number of depressive episodes, mean ± SD | n/a | 1.54 ± 0.66 | 1.73 ± 0.79 | 0.529d |
| Duration of current MDE (months), mean ± SD | n/a | 5.71 ± 5.42 | 14.82 ± 17.70 | 0.127d |
| Cumulative duration of all lifetime MDEs (months), mean ± SD | n/a | 11.48 ± 8.26 | 19.82 ± 16.35 | 0.120d |
| Duration of depressive illness (years), mean ± SD | n/a | 1.59 ± 1.58 | 2.73 ± 1.98 | 0.130d |
| Suicidal ideation/behavior: C-SSRS | ||||
| Severity of ideation (current), n (%) | <0.001d | |||
| 0 = no suicidal ideation | 16 (100%) | 13 (100%) | 0 (0%) | |
| 1 = wish to be dead | 0 (0%) | 0 (0%) | 2 (18.18%) | |
| 2 = non-specific active suicidal thoughts | 0 (0%) | 0 (0%) | 2 (18.18%) | |
| 3 = active suicidal ideation with any method (not plan) without intent to act | 0 (0%) | 0 (0%) | 2 (18.18%) | |
| 4 = active suicidal ideation with some intent to act, without specific plan | 0 (0%) | 0 (0%) | 3 (27.27%) | |
| 5 = active suicidal ideation with specific plan and intent | 0 (0%) | 0 (0%) | 2 (18.18%) | |
| Intensity of ideation (current), mean ± SD | 0 ± 0 | 0 ± 0 | 13.09 ± 3.39 | <0.001d |
| Maximal lifetime SB severity, n (%) | <0.001d | |||
| 0 = none | 16 (100%) | 11 (84.62%) | 0 (0%) | |
| 1 = nonsuicidal self-injurious behavior | 0 (0%) | 2 (15.38%) | 2 (18.18%) | |
| 2 = planning or preparation for attempt | 0 (0%) | 0 (0%) | 0 (0%) | |
| 3 = aborted or interrupted attempt | 0 (0%) | 0 (0%) | 4 (36.36%) | |
| 4 = suicide attempt | 0 (0%) | 0 (0%) | 5 (45.45%) | |
1H-MRS proton magnetic resonance spectroscopy, C-SSRS Columbia Suicide Severity Rating Scale, CDRS-R Children’s Depression Rating Scale, Revised, Dep/SI− depressed without suicidal ideation, Dep/SI+ depressed with suicidal ideation, HC healthy control, MDE major depressive episode, n/a not applicable, SB suicidal behavior, SD standard deviation, SI suicidal ideation.
aThree-group comparisons (HC vs. Dep/SI− vs. Dep/SI+) on demographic characteristics were conducted using one-way ANOVAs for continuous variables and Fisher’s exact tests for categorical variables.
bMissing two observations.
cMissing one observation.
dTwo-group comparisons (Dep/SI− vs. Dep/SI+) on clinical characteristics were conducted using independent samples t-tests for continuous variables and Fisher’s exact tests for categorical variables.