Table 1.
Demographic characteristics
| Variables | Total (N = 2705) |
Antidepressant (−) (N = 1598) |
Antidepressant (+) (N = 1107) |
P value | Scale type | Statistical method |
|---|---|---|---|---|---|---|
| Gender | 0.240 | nominal scale | chi-square test | |||
| Male: n(%) | 1240 (45.8) | 748 (46.8) | 492 (44.4) | |||
| Female: n(%) | 1465 (54.2) | 850 (53.2) | 615 (55.6) | |||
| Body mass index (kg/m2): mean | 23.4 | 23.2 | 23.7 | 0.010 | interval scale | Mann-Whitney U-test |
| Age at study entry: mean | 50.2 | 50.7 | 49.6 | 0.074 | interval scale | Mann-Whitney U-test |
| Age at onset of bipolar symptoms: mean | 34.6 | 34.7 | 34.3 | 0.875 | interval scale | Mann-Whitney U-test |
| Period of attending clinic (yaer): mean | 7.9 | 7.6 | 8.3 | 0.004 | interval scale | Mann-Whitney U-test |
| Current work status: n(%) | 0.594 | nominal scale | chi-square test | |||
| Employed | 1808 (66.8) | 1075 (67.3) | 733 (66.2) | |||
| Unemployed | 897 (33.2) | 523 (32.7) | 374 (33.8) | |||
| Educational level: n(%) | 0.574 | ordinal scale | Mann–Whitney U-test | |||
| Junior high school or high school graduate | 1407 (52.0) | 841 | 566 | |||
| Junior college graduate | 240 (8.9) | 135 | 105 | |||
| College or postgraduate degree | 1058 (39.1) | 622 | 436 | |||
| Mood stabilizer prescription: n (%) | 2251 (83.2) | 1395 (87.3) | 856 (77.3) | < 0.001 | nominal scale | chi-square test |
| Antipsychotics prescription: n (%) | 1449 (53.6) | 892 (55.8) | 557 (50.3) | 0.005 | nominal scale | chi-square test |
| Anxiolytics prescription: n (%) | 1000 (37.0) | 472 (29.5) | 528 (47.7) | < 0.001 | nominal scale | chi-square test |
| Hypnotics prescription: n (%) | 1605 (59.3) | 896 (56.1) | 709 (64.0) | < 0.001 | nominal scale | chi-square test |
| Intelligence Quotient, IQ: n (%) | 0.884 | ordinal scale | Mann-Whitney U-test | |||
| > 85 | 2569 (95.0) | 1517 | 1052 | |||
| 85–71 | 106 (3.9) | 60 | 46 | |||
| < 71 | 30 (1.1) | 21 | 9 | |||
| GAF score: n(%) | < 0.001 | ordinal scale | Mann-Whitney U-test | |||
| 81–100 | 885 (32.7) | 575 (36.0) | 310 (28.0) | |||
| 61–80 | 1243 (46.0) | 739 (46.2) | 504 (45.5) | |||
| 41–60 | 512 (18.9) | 252 (15.8) | 260 (23.5) | |||
| 1–40 | 65 (2.4) | 32 (2.0) | 33 (3.0) | |||
| Psychiatric comorbidity: n (%) | 507 (18.7) | 265 (16.6) | 242 (21.9) | < 0.001 | nominal scale | chi-square test |
| Personality disorder: n (%) | 147 (5.4) | 70 (4.4) | 77 (7.0) | 0.005 | nominal scale | chi-square test |
| Developmental disorder: n (%) | 177 (6.5) | 97 (6.1) | 80 (7.2) | 0.264 | nominal scale | chi-square test |
| Physical comorbidity: n (%) | 821 (30.4) | 468 (29.3) | 353 (31.9) | 0.160 | nominal scale | chi-square test |
| Rapid cycler: n (%) | 299 (11.1) | 169 (10.6) | 130 (11.7) | 0.373 | nominal scale | chi-square test |
| Substance abuse: n (%) | 138 (5.1) | 83 (5.2) | 55 (5.0) | 0.862 | nominal scale | chi-square test |
| Mood status: n(%) | < 0.001 | nominal scale | chi-square test | |||
| Depressive state | 1098 (40.6) | 519 (32.5) | 579 (52.3) | |||
| Manic state | 230 (8.5) | 186 (11.6) | 44 (4.0) | |||
| Mixed state | 261 (9.6) | 159 (9.9) | 102 (9.2) | |||
| Remission | 1116 (41.3) | 734 (45.9) | 382 (34.5) |
p < 0.0025 was regarded as significant using Bonferroni’s correction due to multiple testing
GAF Global Assessment of Function