Table 1 Subject characteristics

Age, mean ± SD

45.0 ± 3.4

50.6 ± 4.7

<0.001

48.5 ± 5.0

Age at onset of bipolar disorder, mean ± SD

14.9 ± 7.1

15.5 ± 8.6

0.82

15.3 ± 8.0

Bipolar diagnosis, N (%)

0.45

 I

11 (53)

17 (48)

28 (50)

 II

7 (33)

16 (45)

23 (41)

 NOS

2 (14)

2 (6)

5 (9)

Duration of illness, mean ± SD

30.0 ± 6.7

35.1 ± 8.6

0.02

33.2 ± 8.3

Rapid cycling, N (%)

13 (61.9)

24 (75)

0.31

37 (69)

Ethnicity, Caucasian, non-Hispanic, N (%)

17 (80)

33 (97)

0.18

50 (91)

Marital status, married/partnered, N (%)

10 (48)

19 (56)

0.55

29 (53)

Employment status, full or part time, N (%)

8 (38)

14 (41)

0.82

22 (40)

BMI, mean ± SD

28.4 ± 5.7

31.3 ± 7.3

0.14

30.1 ± 6.8

Comorbid anxiety, N (%)

19 (90)

33 (94)

0.60

52 (93)

Comorbid alcohol use, N (%)

8 (38)

2 (6)

<0.01

10 (18)

Comorbid substance use, N (%)

3 (14)

8 (23)

0.43

11 (20)

Number of mood stabilizers (Li, AED, and antipsychotics), mean ± SD

1.28 ± 0.8

1.25 ± 0.7

0.88

1.27 ± 0.7