Table 1.
Demographic and clinical characteristics of study participants
| Group; mean ± SD* | ||||||
|---|---|---|---|---|---|---|
|
|
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| Characteristic | Schizophrenia, n = 71 | Bipolar disorder, n = 43 | Healthy controls, n = 196 | Statistical test | p value | Post hoc |
| Age, yr | 28.2 ± 7.8 | 31.3 ± 11.3 | 31.5 ± 7.8 | F = 4.22 | 0.016 | 1 < 2,3 |
| Male sex, no. (%) | 44 (62) | 19 (43.2) | 113 (57.7) | χ2 = 4.15 | 0.13 | |
| Education, yr† | 12.2 ± 2.8 | 13.8 ± 2.3 | 14.5 ± 2.2 | F = 21 | < 0.001 | 1 < 2,3 |
| IQ†‡ | 98.5 ± 15.4 | 110.5 ± 11 | 112.8 ± 10.6 | F = 32.7 | < 0.001 | 1 < 2,3 |
| Age at onset, yr†§ | 22.7 ± 6.1 | 20.7 ± 8.2 | — | t = 1.45 | 0.15 | — |
| Duration of illness, yr†¶ | 5.3 ± 5.3 | 10.7 ± 9.4 | — | t = −3.81 | < 0.001 | — |
| Symptom rating† | ||||||
| PANSS total | 58.1 ± 13.7 | 41.3 ± 7.4 | — | t = 7.4 | < 0.001 | — |
| PANSS positive | 13.3 ± 4.9 | 8.3 ± 2.2 | — | t = 6 | < 0.001 | — |
| PANSS negative | 14.8 ± 5 | 9.2 ± 2.7 | — | t = 6.7 | < 0.001 | — |
| PANSS general | 30 ± 6.8 | 23.5 ± 4.6 | — | t = 6 | < 0.001 | — |
| GAF symptom | 46.1 ± 14 | 60.2 ± 10.1 | — | t = −5.7 | < 0.001 | — |
| GAF function | 47 ± 12.4 | 57.9 ± 11.8 | — | t = −4.6 | < 0.001 | — |
| Medication, no. (%); defined daily dose†** | ||||||
| Antipsychotics | 59 (93.7); 1.33 ± 1.25 | 22 (51.2); 0.88 ± 0.58 | — | t = 1.87 | 0.07 | — |
| Lithium | 5 (7.9); 0.65 ± 0.23 | 10 (27); 1.07 ± 0.44 | — | t = −1.98 | 0.07 | — |
| Antiepileptic | 3 (4.8); 0.34 ± 0.33 | 8 (21.2); 1.07 ± 0.33 | — | t = −3.52 | 0.008 | — |
| Antidepressants | 21 (33.3); 2.51 ± 4.19 | 13 (35.1); 1.34 ± 0.88 | — | t = 1.01 | 0.32 | — |
BD = bipolar disorder; GAF = Global Assessment of Functioning; PANSS = Positive and Negative Syndrome Scale; SD = standard deviation.
Unless indicated otherwise.
Data missing in the following categories: education (15 schizophrenia, 5 BD, 11 controls), IQ (12 schizophrenia, 4 BD, 11 controls), age at onset and duration of illness (6 schizophrenia), symptom rating (4 schizophrenia) and medication (8 schizophrenia, 6 BD).
Measured using the Wechsler Abbreviated Scale of Intelligence.
Defined as age at first symptom of psychosis for patients with schizophrenia and depression/mania/hypomania for patients with BD.
Defined as the number of years between age at onset and age at MRI scanning.
Some patients were taking more than 1 medication.