Clinical variable | Early onset diagnostic subgroup | χ 2 or t | P | |
---|---|---|---|---|
Bipolar disorder type 1 (N = 169) | Bipolar disorder type 2 (N = 142) | |||
Female (%) | 96 (56.8) | 85 (59.9) | 0.3 | 0.6 |
Age at interview, mean (SD) | 45.3 (13.5) | 42.8 (14.4) | 1.5 | 0.01 |
Presence of family history of any psychiatric disorder (%) | 99 (58.9) | 93 (65.5) | 1.4 | 0.2 |
Presence of family history of mood disorder (%) | 85 (52.5) | 84 (60.0) | 1.7 | 0.2 |
Presence of family history of bipolar disorder (%) | 31 (18.5) | 36 (25.4) | 2.2 | 0.1 |
Number of manic/hypomanic episodes, mean (SD) | 4.4 (5.1) | 4.3 (4.2) | 0.2 | 0.8 |
Number of depressive episodes, mean (SD) | 5.5 (4.7) | 6.0 (5.6) | −0.8 | 0.4 |
Illness duration, mean (SD) | 22.5 (12.8) | 21.9 (13.7) | 0.4 | 0.7 |
Lifetime comorbidity with substance dependence (%) | 15 (8.9) | 8 (5.6) | 1.2 | 0.3 |
Lifetime comorbidity with alcohol dependence (%) | 10 (5.9) | 19 (13.4) | 5.1 | 0.02 |
Presence of suicidal behaviour (%) | 47 (28.0) | 45 (31.7) | 0.5 | 0.5 |
Type of clinical course cycle | ||||
MDI (%) | 75 (44.4) | 51 (35.9) | 10.4 | 0.035 |
DMI (%) | 20 (11.8) | 31 (21.8) | ||
Irregular cycling (%) | 65 (38.5) | 58 (40.8) | ||
Continuous cycling (%) | 5 (3.0) | 2 (1.4) | ||
Rapid cycling (%) | 4 (2.4) | 0 (0.0) |