A comparison of symptoms of bipolar and unipolar depression in postpartum women

Background: Distinguishing postpartum women with bipolar from unipolar depression remains challenging, particularly in obstetrical and primary care settings. The post-birth period carries the highest lifetime risk for the onset or recurrence of Bipolar Disorder (BD). Characterization of differences between unipolar and bipolar depression symptom presentation and severity is critical to differentiate the two disorders. Methods: We performed a secondary analysis of a study of 10,000 women screened by phone with the Edinburgh Postnatal Depression Scale at 4–6 weeks post-birth. Screen-positive mothers completed the Structured Clinical Interview for DSM-4 and those diagnosed with BD and unipolar Major Depressive Disorder (UD) were included. Depressive symptoms were assessed with the 29-item Structured Interview Guide for the Hamilton Rating Scale for Depression (SIGH-ADS). Results: The sample consisted of 728 women with UD and 272 women with BD. Women with BD had significantly elevated levels of depression severity due to the higher scores on 8 of the 29 SIGH-ADS symptoms. Compared to UD, women with BD had significantly higher rates of comorbid anxiety disorders and were twice as likely to report sexual and/or physical abuse. Limitations: Only women who screened positive for depression were included in this analysis. Postpartum women with unstable living situations, who were hospitalized or did not respond to contact attempts did not contribute data. Conclusions: Severity of specific symptom constellations may be a useful guide for interviewing postpartum depressed women along with the presence of anxiety disorder comorbidity and physical and/or sexual abuse.