Gender differences in bipolar-II disorder

Gender differences in bipolar-II disorder (BP-II) are understudied. Study aim was to test if there were gender differences in the clinical and family history features of BP-II. Methods: Consecutive 374 BP-II private practice outpatients were interviewed by a senior psychiatrist using the Structured Clinical Interview for DSM-IV, modified to improve the detection of BP-II (by Benazzi and Akiskal 2003, J Affect Disord 73: 33 - 38), the Montgomery Asberg Depression Rating Scale (MADRS), the Hypomania Interview Guide, and the Family History Screen. Logistic regression was used to study associations and control for confounding. Alpha level was set at 0.05; P was two-tailed. Results: Females represented 67.3% of the group. The female to male ratio was independent of age. Females were more common in younger onset BP-II. Females, versus males, had significantly lower age at onset, more axis I comorbidity, atypical depressions, intra-depression hypomanic symptoms (i.e., mixed depression), and family history of suicidal behavior. On the MADRS, females had more sadness, loss of energy, loss of interest, and suicidal ideas. The symptom structure of hypomanic episodes was similar between females and males. Limitations Single interviewer, outpatient sample, private practice study setting. Discussion: Clinical differences were found between BP-II females and males. Differences were found only on the depressive pole of the disorder. However, the magnitude of the differences had not a strong clinical significance, suggesting that at present, on the basis of the variables and the population studied, there is little ground to support a female BP-II depression.