Table 1 Demographic and clinical variables of the study population

Age (years), mean ± SD

46.57 ± 9.21

48.48 ± 8.98

45 ± 9.26

0.18

Gender (male/female)

31/20

14/9

17/11

1

Bipolar (I/II)

33/18

12/11

21/7

0.14

Age at onset (years), mean ± SD

25.14 ± 11.24

24.43 ± 10.86

25.71 ± 11.71

0.69

Number depressive episodes (mean ± SD)

12.98 ± 15,79

10.55 ± 11,69

15.04 ± 18.56

0.31

Number mania/hypomania (mean ± SD)

8.87 ± 11.78

6.62 ± 9.11

10.76 ± 13.53

0.22

Number of drugs (mean ± SD)

2.41 ± 1.22

2.57 ± 1.20

2.29 ± 1.24

0.42

Rapid cycling (no/yes)

46/5

22/1

24/4

0.35

HAMD (mean ± SD)

6.39 ± 5.05

4.61 ± 3.13

7.86 ± 5.86

0.02

BDI (mean ± SD)

32 ± 8.84^a

29.39 ± 5.66

33.50 ± 10.93^a

0.09

YMRS (mean ± SD)

2.10 ± 2,56

2.04 ± 2,01

2.14 ± 2.98

0.88