Table 1.
Sample characteristics.
| Group | SZ | BD | HC | Group comparisons |
||
|---|---|---|---|---|---|---|
| SZ vs. BD | SZ vs. HC | BD vs. HC | ||||
| Demographics, education | ||||||
| Total N | 223 | 190 | 284 | |||
| Sex (% female) | 95 (42.6) | 111 (58.4) | 134 (47.2) | χ2 = 9.65, p = 1.89E-03 | χ2 = 5.32, p = 2.11E-02 | χ2 = 0.88, p = 3.48E-01 |
| Age (years) | 32.10 ± 9.31 | 34.99 ± 11.31 | 35.22 ± 9.60 | t = − 2.73, p = 1.96E-02 | t = − 3.42, p = 1.99E-03 | t = − 0.37, p = 1 |
| Education (years) | 12.75 ± 2.49 | 13.50 ± 2.27 | 14.15 ± 2.26 | t = − 2.36, p = 5.62E-02 | t = − 5.43, p < 1E-04 | t = − 2.81, p = 1.54E-02 |
| Ethnicity (% caucasian) | 180 (80.7) | 171 (90) | 280 (98.5) | |||
| Cognitive domains mean z ± sd (n) | ||||||
| g | − 1.64 ± 2.45 (181) | − 0.01 ± 2.20 (177) | 1.08 ± 1.58 (278) | t = − 7.58, p < 1E-04 | t = − 14.59, p < 1E-04 | t = − 6.19, p < 1E-04 |
| Processing speed | − 0.63 ± 0.92 (193) | − 0.13 ± 0.92 (177) | 0.51 ± 0.82 (283) | t = − 5.76, p < 1E-04 | t = − 14.90, p < 1E-04 | t = − 8.33, p < 1E-04 |
| Verbal learning/memory | − 0.45 ± 0.83 (194) | 0.06 ± 0.90 (178) | 0.25 ± 0.72 (284) | t = − 6.07, p < 1E-04 | t = − 9.83, p < 1E-04 | t = − 2.99, p = 8.56E-03 |
| Executive function | − 0.53 ± 0.87 (193) | − 0.01 ± 0.69 (178) | 0.37 ± 0.49 (284) | t = − 7.08, p < 1E-04 | t = − 14.41, p < 1E-04 | t = − 6.41, p < 1E-04 |
| Working memory/attention | − 0.35 ± 0.89 (194) | − 0.07 ± 1.01 (177) | 0.28 ± 0.99 (284) | t = − 3.17, p = 4.79E-03 | t = − 7.33, p < 1E-04 | t = − 3.72, p = 6.5E-04 |
| Symptomsamean ± sd (n) | ||||||
| Duration of illnessb | 10.33 ± 8.15 (220) | 13.69 ± 9.91 (188) | na | t = − 3.7, p = 2.4E-04 | ||
| PANSS negative | 15.55 ± 6.59 (220) | 10.11 ± 3.60 (186) | na | t = 10.5, p < 1E-04 | ||
| PANSS positive | 14.86 ± 5.38 (219) | 10.08 ± 3.64 (187) | na | t = 10.6, p < 1E-04 | ||
| PANSS total | 62.18 ± 17.21 (217) | 45.59 ± 10.12 (186) | na | t = 12, p < 1E-04 | ||
| Drug use n (%) | ||||||
| Alcohol use last month | 131 (58.7) | 139 (73.2) | 213 (75.0) | |||
| Amphetamine last month | 8 (3.6) | 2 (1.1) | 1 (0.4) | |||
| Cocaine use last month | 4 (1.8) | 3 (1.6) | 2 (0.7) | |||
| Cannabis use last month | 17 (7.6) | 16 (8.4) | 3 (1.1) | |||
| AUDIT score mean ± sd (n) | 6.51 ± 5.87 (198) | 8.05 ± 5.83 (178) | 6.10 ± 2.93 (247) | |||
| Medication n (%) | ||||||
| Antipsychotic | 179 (80.3) | 74 (38.9) | na | |||
| Lithium | 2 (0.9) | 35 (18.4) | na | |||
| Antiepileptic | 29 (13.0) | 82 (43.2) | na | |||
| Antidepressant | 57 (25.6) | 52 (27.4) | na | |||
| Hospitalization (mean ± sd) | 2.4 (3.3) | 1.6 (2.3) | na | |||
| Polygenic risk scores (PGRS) (total N = 505) | ||||||
| N | 145 | 144 | 216 | |||
| SZ PGRS (mean ± sd) | 0.34 ± 0.94 | 0.11 ± 1.01 | − 0.30 ± 0.94 | t = 1.72, p = 2.57E-01 | t = 6.05, p < 1E-04 | t = 4.13, p = 1.26E-04 |
| BD PGRS (mean ± sd) | 0.03 ± 0.99 | 0.22 ± 0.96 | − 0.17 ± 1.01 | t = − 1.62, p = 3.16E-01 | t = 1.84, p = 2E-01 | t = 3.61, p = 1E-03 |
AUDIT: Alcohol Use Disorders Identification Test. SZ = Schizophrenia, BD = Bipolar Disorder, HC = Controls.
a
The median time period between the clinical assessment and MRI scan was 155 days.
b
Defined as years between age at the first occurrence of any psychiatric illness episode (psychotic, affective, or other) and date of MRI scan.