[Bipolarity among unipolar affective disorder patients--uniDEP-BI national multi-site study]

The main objective of the study was to evaluate the occurrence of bipolarity among outpatients with a recurrent major depressive disorder.

The uniDEP-BI study was conducted throughout Poland by 96 psychiatrists from 16 sites, who were trained in the study instruments. The sample was selected from the population of outpatients with at least one depressive episode (n = 880). The final study group included 246 working age adults (75.2% of females) treated for recurrent unipolar disorder. The study questionnaire consisted in the DSM-IV criteria of major depressive episode, (hypo)manic episode, criteria for bipolar spectrum disorder by Ghaemi et al.

Unipolar mood disorder was confirmed in 32.9% cases, bipolar I disorder was found in 19.5%, bipolar II in 35% and bipolar spectrum disorder in 12.6% of the assessed patients. Patients with bipolar compared to the unipolar mood disorder had significantly more frequently a family history of bipolar disorder, short (hypo)manic episodes after antidepressive treatment, premorbid cyclo-, hyperthymic or impulsive (borderline type) personality, recurrent depressive episodes, atypical depressive symptoms, early onset of depression (< 25 yrs), distracted attention and panic attacks. Subjects with confirmed recurrent depressive disorder were significantly more often working (37.2% vs. 22.7%). Duration of the illness was significantly shorter and the number of previous depressive episodes was significantly lower in this group.

The findings showed that the bipolarity features are more common among patients with unipolar mood disorders. It also points to a need of proper and deeper diagnostics of affective disorders and verification of rules and period of antidepressive and normothymic treatment.