Psychiatric comorbidities in patients with major depressive disorder and patients with bipolar II depression in a psychiatric setting

Abstract

Objective This report aimed at exploring magnitude of psychiatric comorbidities of patients with major depressive disorder (MDD) or bipolar Ⅱ depression. Comorbidity patterns between MDD and bipolar Ⅱ depression were compared and the association of clinical presentation with the two types of depressive episodes were analyzed. Methods A cross-sectional survey was conducted on a total of 833 patients that met the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition Text Revision criteria for MDD or bipolar Ⅱ depression with current major depressive episodes who were seeking help in a psychiatric hospital were enrolled. Endorsement of comorbid psychiatric disorders were based on the MINI-International Neuropsychiatric Interview (Chinese version). Psychiatric comorbidities were compared between the two groups and the binary logistic model was developed to estimate association of endorsement of psychiatric comorbidities with the two types of depressive episodes. Results Up to 68.0% (70/125) of participants with bipolar Ⅱ depression and 53.1% (277/708) of participants with MDD adopted at least one psychiatric comorbidity (χ2=9.534, P=0.002). Significant difference of presence of agoraphobia (without panic attack) (26.4% (33/125) vs. 8.1% (57/708), χ2=31.118, P=0.000), social anxiety disorder (21.6% (27/125) vs. 11.4% (81/708), χ2=9.718, P=0.002), psychosis (11.2% (14/125) vs. 2.4% (17/708), χ2= 22.957, P=0.000) and eating disorders (3.2%(4/125) vs. 0.7%(5/708), P=0.033) were detected between the two groups. Comorbid agoraphobia (OR=3.332, 95% CI 1.970- 5.635, P=0.000) or psychosis (OR=3.432, 95% CI 1.543-7.632, P=0.002), and endorsement of recurrent depression (OR=2.457, 95% CI 1.625-3.714, P=0.000) or attempted suicides (OR=1.764, 95% CI 1.045-2.975, P=0.033) was associated with bipolar Ⅱ depression. Conclusions MDD and bipolar Ⅱ depression differed in comorbidity patterns although psychiatric comorbidities are both commonly seen in the two conditions. A comprehensive assessment on comorbidity pattern and recognition of differential clinical presentations of bipolar Ⅱ depression versus MDD may be helpful to guide clinicians to more accurate diagnoses. Key words: Depressive disorder; Bipolar disorder; Comorbidity