Abstract
Objective: The aim of this study to investigate the differences between depressive episodes of disorder type I (BD-I), type II (BD-II) and unipolar depression (UD).
Methods: For this purpose patients from outpatients or inpatients units have been included in the study. Fourty-nine patients who were diagnosed with BD-I depressive episode, 47 patients who were diagnosed with BD-II depressive episode, and 46 patient who were diagnosed with major depressive episode (UD) according to DSM-IV have been evaluated consecutively. Exclusion criterion was ordered treatment for current episode. Diagnostic interviews were done with SCID-I and II, information about patient and disease were recorded by using SKIP-TURK. Hamilton Depression Rating Scale (HDRS), Suicide Intent Scale (SIS), Barratt Impulsivity Scale (BIS), The Eating Attitudes Test (EAT), Pittsburg Sleep Quality Index (PSQI) and Arizona Sexual Experience Scale (ASES) were used to evaluate each patient.
Results: Melancholic features and psychotic symptoms were more frequent in BD-I, atypical features and suicid attempt were more frequent in BD-II. Sudden onset and seasonality were mostly found in BD-II. However, item scores of HDRS, except items assessing middle and terminal insomnia, genital symptoms, and insight, were different between the groups. There was a strong relation between HDRS and BIS scores in UD, a moderate relation between BIS and PSQI scores in BD-I, and a moderate relation between BIS and EAT scores in BD-II patients.
Conclusion: Although some similarities in the characteristics of depressive episodes of mood disorders exist, there are some remarkable differences between them that can be useful in differential diagnosis and treatment.

Key words: bipolar depression, unipolar depression, bipolar disorder type II