Table 1.
Descriptive and Clinical Characteristics of Patients and Healthy Volunteers
| Healthy Volunteers (n=24)† | nTRD MDD (n=18)† | TRD (n=15)† | |
|---|---|---|---|
| Age, mean (SD), y | 37.25 (13.5); range: 21–60 | 38.3 (12.3) range: 23–65 | 46.80 (11.9)a range: 28–68 |
| Female, No. (%) | 13 (54%) | 6 (33%) | 7 (47%) |
| Non-hispanic Caucasian, No. (%) | 13 (54%) | 8 (44%) | 12 (80%) |
| IQ, mean (SD) | 114.95 (10.3) | 111.12 (16.0) | 112.64 (12.1) |
| Years of education, mean (SD) | 16.38 (1.9) | 15.38 (2.9) | 14.00 (2.6)a |
| Median household annual income | $35,000–49,999 | $15,000–34,999 | $15,000–34,999 |
| HH-SES, mean (SD) | 50.29 (10.7) | 43.67 (15.3) | 46.47 (9.8) |
| Body Mass Index, mean (SD), kg/m2 | 26.27 (4.6) | 26.83 (4.3) | 27.72 (4.9) |
| Family History of Mood Disorder, No. (%) | 1 (4%) | 5 (31%) c | 6 (40%) a |
| Any Comorbid Anxiety Disorder, No. (%) | - | 13 (72%) | 11 (73%) |
| Social Phobia | 9 (50%) | 5 (33%) | |
| Obsessive Compulsive Disorder | 2 (11%) | 1 (7%) | |
| Post-Traumatic Stress Disorder | 2 (11%) | 2 (13%) | |
| Panic Disorder | 0 (0%) | 1 (7%) | |
| Specific Phobia | 1 (6%) | 0 (0%) | |
| Generalized Anxiety Disorder | 5 (28%) | 1 (7%) | |
| Anxiety Disorder Not Otherwise Specified | 3 (17%) | 5 (33%) | |
| MDD Subtypes, No. (%) | - | ||
| Atypical | 1 (6%) | 3 (20%) | |
| Melancholic | 1 (6%) | 1 (7%) | |
| Psychotic | 2 (11%) | 1 (7%) | |
| Antidepressant NaÏve, No. (%) | - | 9 (50%) | 0 (0%)b |
| 2-week Washout Period, No. (%) | - | 2 (11%) | 7 (47%)b |
| Time Since Illness Onset, mean (SD), y | - | 21.80 (16.4) | 26.93 (10.8) |
| Age-of-Onset, mean (SD), y | - | 17.73 (14.3) | 22.20 (15.4) |
| Number of Episodes, mean (SD) | - | 2.73 (4.8) | 2.00 (2.1) |
| Single Episode (Non-remitting), No. (%) | - | 11 (61%) | 10 (67%) |
| Duration of Current Episode >= 2y, No. (%) | - | 15 (83%) | 15 (100%) |
| Number of Failed Trials in Current Episode, mean (SD) | - | 0.89 (0.9) | 5.43 (2.8)b |
| HRSD17, mean (SD) | 0.84 (0.9) | 17.94 (5.5)c | 24.40 (5.1)a,b |
| QIDS-SR16, mean (SD) | 1.34 (1.5) | 13.11 (4.0)c | 18.13 (4.1)a,b |
| HAM-A, mean (SD) | 1.42 (1.3) | 19.44 (6.9)c | 27.00 (7.9)a,b |
| SDS, mean (SD) | - | 17.06 (5.7) | 19.14 (10.5) |
Note: Continuous variables compared by ANOVA w/LSD post-hoc comparisons, dichotomous variables compared by Fisher’s exact test, 2-tailed; HV = Healthy Volunteer; nTRD MDD = Non-Treatment-Resistant Major Depressive Disorder; TRD = Treatment-Resistant Depression; HH-SES = Hollingshead Four-Factor Index of Social Position; HRSD17 = Hamilton Rating Scale for Depression, 17-item; QIDS-SR16 = Quick Inventory of Depressive Symptoms-Self-Report; HAM-A = Hamilton Anxiety Rating Scale; SDS = Sheehan Disability Scale (18–22)
Descriptives are presented for subjects with interpretable occipital lobe MRS data; for ACC analyses, 3 HVs, 2 nTRD MDDs, and 3 TRD participants had uninterpretable data due to motion-degraded spectral quality
TRDs differ from HVs, p < .05
TRDs differ from nTRD MDDs, p < .05
nTRD MDDs differ from HVs, p < .05