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

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