Table 1.
Baseline demographic and clinical characteristics
| Prolonged-release melatonin N = 20 | Placebo N = 28 | |||
|---|---|---|---|---|
| N | % | N | % | |
| Men | 11 | 55.0 | 18 | 64.3 |
| Diagnosis | ||||
| Paranoid schizophrenia | 15 | 75.0 | 23 | 82.1 |
| Non-paranoid schizophrenia | 0 | 0 | 2 | 7.1 |
| Schizoaffective disorder | 2 | 10.0 | 0 | 0 |
| Bipolar affective disorder | 3 | 15.0 | 3 | 10.7 |
| Housing | ||||
| Living independently | 17 | 85.0 | 19 | 67.8 |
| Supported housing | 1 | 5.0 | 0 | 0 |
| Institution | 2 | 10.0 | 9 | 32.1 |
| Occupational status | ||||
| Employed | 0 | 0 | 0 | 0 |
| Financial aid/cash subsidies | 0 | 0 | 2 | 7.1 |
| Disability pension | 18 | 90.0 | 44 | 91.7 |
| Other | 2 | 10.0 | 2 | 4.2 |
| Benzodiazepine treatment | ||||
| One drug | 15 | 75.0 | 22 | 78.6 |
| Two drugs | 5 | 25.0 | 6 | 21.4 |
| Clonazepam | 11 | 55.0 | 30 | 62.5 |
| Diazepam | 0 | 0 | 1 | 2.0 |
| Oxazepam | 5 | 25.0 | 9 | 18.8 |
| Nitrazepam | 2 | 10.0 | 4 | 8.3 |
| Lorazepam | 0 | 0 | 1 | 2.1 |
| Zopiclone | 2 | 10.0 | 2 | 4.2 |
| Zolpidem | 0 | 0 | 1 | 3.6 |
| Antipsychotic drug treatment | ||||
| One drug | 12 | 60.0 | 13 | 46.4 |
| Two drugs | 7 | 35.0 | 11 | 39.3 |
| ≥ Three drugs | 1 | 5.0 | 14 | 14.3 |
| Antidepressant drug treatment | ||||
| ≥ One drug | 14 | 70.0 | 14 | 50.0 |
| Mood stabilizer drug treatment | ||||
| ≥ One drug | 6 | 30.0 | 7 | 25.0 |
| Anticholinergic drug treatment | ||||
| One drug | 1 | 5.0 | 7 | 25.0 |
| Mean | SD | Mean | SD | |
| Age, years | 47.7 | 8.2 | 45.9 | 10.3 |
| Duration of illness, years | 23.3 | 12.7 | 18.9 | 8.1 |
| PANSS total score | 61.1 | 15.2 | 64.5 | 12.5 |
| Benzodiazepine treatment duration, years | 11.3 | 9.1 | 11.6 | 7.2 |
| Benzodiazepine total dose, mg diazepam equivalents | 25.1 | 24.3 | 25.5 | 14.1 |
| Total antipsychotic dose, mg olanzapine equivalents | 17.7 | 11.5 | 27.6 | 25.2 |
| IS | 0.63 | 0.10 | 0.57 | 0.10 |
| IV | 0.74 | 0.21 | 0.85 | 0.26 |
| RA | 0.85 | 0.10 | 0.87 | 0.09 |
PANSS positive and negative syndrome scale, IS interdaily stability, IV intradaily variability, RA relative amplitude
No statistically significant differences (p < 0.05) between groups at baseline (categorical variables evaluated with chi-square test and continuous variables evaluated with independent t-test)