Table 1.
Demographic data and clinical characteristics of participants.
| Characteristic | Schizophrenia (n = 71) | Controls (n = 57) | P-value |
|---|---|---|---|
| Age, mean (SD) years | 40 (10) | 40 (11) | 0.702a |
| Gender, n (%) males | 53 (75) | 35 (61) | 0.108b |
| RIN, mean (SD) | 8.4 (0.9) | 8.7 (0.3) | 0.006a* |
| Ancestry, n (%) CEU | 62 (90) | 50 (88) | 0.742b |
| Substance use in past 3 months, n (%) | |||
| Tobacco (smoked) | 33 (47) | 12 (21) | 0.003b* |
| Alcohol | 59 (83) | 55 (97) | 0.016b* |
| Cannabis | 11 (15) | 7 (12) | 0.385b |
| Amphetamine | 4 (6) | 2 (4) | 0.439b |
| Cocaine | 0 (0) | 2 (4) | 0.137b |
| Opiates | 1 (1) | 1 (2) | 0.990b |
| Clozapine plasma level, mean (SD) μg/L | 432 (234) | – | – |
| Chlorpromazine equivalent (excluding clozapine) dosage mean (SD) mg/day | 142 (286) | – | – |
| Age of onset, mean (SD) years | 22.5 (6) | – | – |
| Duration of illness, mean (SD) years | 17 (8) | – | – |
| PANSS scores, mean (SD) | |||
| Positive | 10 (6) | – | – |
| Negative | 15 (5) | – | – |
| Disorganized | 8 (3) | – | – |
| Excitement | 6 (2) | – | – |
| Depression | 6 (3) | – | – |
| Total | 62 (14) | – | – |
CEU, Northern and Western European ancestry; TRS, treatment-resistant schizophrenia; RIN, RNA integrity number; PANSS, Positive and Negative Syndrome Scale.
aIndependent sample t-test.
bChi-square (χ2) test.
*P < 0.05.