Table 1.
Sociodemographic and clinical differences between patients diagnosed with bipolar I disorder (N = 587) and bipolar II disorder (N = 221). Pearson’s chi-squared tests (or Fisher’s exact test [*]) has been used for categorical variables, Wilcoxon rank-sum test for continuous variables. P < 0.05 are shown in bold. Pairwise Fisher’s exact test was used for post-hoc comparisons of multinomial variables, using Benjamini–Hochberg procedure as false discovery rate (FDR) correction method. Pairwise significant differences (FDR-p < 0.05) between individual categories are indicated with lowercase letters. Abbreviations: M = median; IQR = interquartile range; SMD = standardized mean difference
| Bipolar I disorder | Bipolar II disorder | |||
|---|---|---|---|---|
| Sociodemographic variables | N (%) / M [IQR] | N (%) / M [IQR] | SMD | p |
| Age (years) | 44.09 [34.80, 53.59] | 47.99 [38.75, 58.17] | 0.201 | 0.005 |
| Sex (female) | 335 (57.1) | 147 (66.5) | 0.195 | 0.018 |
| Marital status* | 0.420 | < 0.001 | ||
| Single | 137 (33.9) | 29 (17.8) | a,b | |
| Married | 170 (42.1) | 94 (57.7) | a | |
| Divorced | 91 (22.5) | 34 (20.9) | ||
| Widowed | 6 (1.5) | 6 (3.7) | b | |
| Socioeconomic status | 0.375 | 0.024 | ||
| Work full-time | 86 (22.4) | 23 (15.1) | ||
| Work part-time | 35 (9.1) | 11 (7.2) | ||
| Unemployment insurance | 33 (8.6) | 10 (6.6) | ||
| Social assistance | 48 (12.5) | 20 (13.2) | ||
| Disabled | 106 (27.6) | 36 (23.7) | ||
| Other | 21 (5.5) | 17 (11.2) | ||
| Retired | 29 (7.6) | 23 (15.1) | ||
| Student | 26 (6.8) | 12 (7.9) | ||
| General Assessment of Functioning (GAF) score | 70.00 [60.00, 80.00] | 70.00 [60.00, 80.00] | 0.049 | 0.828 |
| Mood disorder features | ||||
| Age at onset of major depression (years) | 20.00 [16.00, 26.00] | 22.00 [16.00, 28.00] | 0.134 | 0.373 |
| Age at onset of mania or hypomania (years) | 25.00 [19.00, 33.00] | 28.00 [20.00, 37.00] | 0.230 | 0.022 |
| Age at onset of mood disorders (years) | 22.00 [17.00, 29.00] | 23.00 [18.00, 31.00] | 0.095 | 0.389 |
| Age at first psychiatric treatment (years) | 31.00 [23.00, 40.00] | 38.00 [28.75, 47.00] | 0.437 | < 0.001 |
| Illness duration (years) | 19.00 [11.00, 29.00] | 22.00 [12.00, 30.00] | 0.146 | 0.048 |
| Illness duration before treatment | 0.409 | 0.010 | ||
| Treatment before mood disorder onset | 33 (11.7) | 8 (6.7) | ||
| Early treatment (from onset to 2 years after) | 87 (31.0) | 22 (18.3) | a | |
| Average delay (3 to 9 years from onset) | 61 (21.7) | 29 (24.2) | ||
| Late treatment (9 to 10 years from onset) | 51 (18.1) | 26 (21.7) | ||
| Very late treatment (20 or more years from onset) | 49 (17.4) | 35 (29.2) | a | |
| Psychiatric comorbidity | ||||
| Social anxiety | 90 (20.2) | 45 (25.1) | 0.119 | 0.210 |
| Panic disorder | 95 (20.5) | 43 (24.2) | 0.087 | 0.370 |
| Generalized anxiety | 133 (29.9) | 61 (33.9) | 0.086 | 0.377 |
| Obsessive compulsive disorder | 49 (10.6) | 25 (14.2) | 0.109 | 0.258 |
| Substance use disorders | 163 (35.2) | 47 (26.7) | 0.185 | 0.051 |
| Attention-deficit/hyperactivity disorders | 23 (5.3) | 10 (5.9) | 0.025 | 0.933 |
| Learning disabilities | 21 (4.8) | 10 (5.8) | 0.043 | 0.774 |
| Primary insomnia | 43 (9.9) | 33 (19.1) | 0.263 | 0.003 |
| Personality disorders | 52 (12.1) | 21 (12.7) | 0.018 | 0.958 |
| Medical history | ||||
| Diabetes mellitus | 44 (11.0) | 15 (9.0) | 0.065 | 0.586 |
| Hypertension | 48 (12.2) | 32 (19.4) | 0.200 | 0.036 |
| Menstrual abnormalities | 61 (30.0) | 34 (33.3) | 0.071 | 0.650 |
| Thyroid problems | 88 (22.2) | 51 (32.3) | 0.229 | 0.018 |
| Head injury | 96 (28.1) | 29 (21.0) | 0.165 | 0.139 |
| Neurological comorbidity | 15 (4.7) | 7 (5.4) | 0.031 | 0.953 |
| Migraine | 59 (15.4) | 45 (29.2) | 0.335 | < 0.001 |
| Family history | ||||
| Bipolar disorder (proportion of first-degree relatives affected) | 0.00 [0.00, 0.03] | 0.00 [0.00, 0.03] | 0.003 | 0.960 |
| Major depressive disorder (proportion of first-degree relatives affected) | 0.00 [0.00, 0.20] | 0.12 [0.00, 0.25] | 0.189 | 0.011 |
| Schizophrenia (proportion of first-degree relatives affected) | 0.00 [0.00, 0.00] | 0.00 [0.00, 0.00] | 0.057 | 0.982 |
| Schizoaffective disorder (proportion of first-degree relatives affected) | 0.00 [0.00, 0.00] | 0.00 [0.00, 0.00] | 0.034 | 0.659 |
| Anxiety disorders (proportion of first-degree relatives affected) | 0.00 [0.00, 0.00] | 0.00 [0.00, 0.00] | 0.083 | 0.040 |
| Other psychiatric disorders (proportion of first-degree relatives affected) | 0.14 [0.00, 0.33] | 0.20 [0.00, 0.33] | 0.142 | 0.180 |
| First-degree family history of completed suicide | 33 (8.1) | 12 (7.6) | 0.019 | 0.980 |
| First-degree family history of suicide attempt | 83 (20.5) | 43 (27.7) | 0.169 | 0.087 |
| First- or second-degree family history of completed suicide | 72 (18.0) | 24 (15.6) | 0.063 | 0.592 |
| First- or second-degree family history of suicide attempt | 129 (32.3) | 51 (33.6) | 0.026 | 0.864 |