Demographic characteristics of patients with schizophrenia and bipolar disorder and heathy controls
| Variable | Control* n = 205 | Bipolar disorder* n = 51 | Schizophrenia* n = 157 | p value (F or χ2) | Post hoc analysis |
|---|---|---|---|---|---|
| Age, yr | 35.2 ± 13.6 | 46.5 ± 16.0 | 42.8 ± 13.6 | 2.63 × 10−9 (20.7) | HC < BD, SCZ |
| Sex (no. of males/females) | 133/72 | 27/24 | 62/95 | 9.80 × 10−6 (23.1)† | — |
| Education, yr | 16.3 ± 2.4 | 14.1 ± 2.3 | 12.5 ± 2.1 | 1.19 × 10−42 (123.3) | HC > BD > SCZ |
| Estimated premorbid IQ | 109.3 ± 7.3 | 105.6 ± 10.3 | 98.9± 11.4 | 4.21 × 10−20 (50.3) | HC > BD > SCZ |
| Handedness (right/left/bilateral) | 194/11/0 | 49/1/1 | 150/7/0 | 0.25 (8.2)‡ | — |
| CPZ-eq, mg/d | — | 115.7 ± 149.4 | 500.3 ± 513.7 | 3.48 × 10−7 (27.7) | — |
| BPD-eq, mg/d | — | 0.0 ± 0.3 | 0.9 ± 2.4 | 0.016 (5.9) | — |
| IMI-eq, mg/d | — | 51.6 ± 97.3 | 2.9 ± 20.6 | 1.46 × 10−8 (34.8) | — |
| Age at onset, yr | — | 33.6 ± 14.0 | 26.9 ± 11.1 | 4.92 × 10−4 (12.5) | — |
| Duration of illness, yr | — | 13.0 ± 11.6 | 16.2 ± 12.1 | 0.10 (2.7) | — |
| PANSS positive symptoms score | — | — | 16.1 ± 6.1 | — | — |
| PANSS negative symptoms score | — | — | 18.4 ± 6.9 | — | — |
| HAMD-17 score | — | 11.0 ± 6.5 | — | — | — |
| YMRS score | — | 2.4 ± 3.9 | — | — | — |
BD = bipolar disorder; BPD-eq = biperiden equivalents of total antiparkinsonian drugs; CPZ-eq = total antipsychotic dosage in chlorpromazine equivalents; HAMD-17 = 17-item Hamilton Rating Scale for Depression; HC = healthy control; IQ = intelligence quotient; IMI-eq = imipramine equivalents of total antidepressants; PANSS = Positive and Negative Syndrome Scale; SCZ = schizophrenia; YMRS = Young Mania Rating Scale.
↵* Values are mean ± standard deviation unless otherwise indicated.
↵† χ2 test.
‡ Fisher exact test.
Complete demographic information was not obtained for all particpants (number for which the estimated premorbid IQ was available: SCZ, n = 149; BD, n = 48; HC, n = 187).