Is there a relationship between depression with anxious distress DSM-5 specifier and bipolarity? A multicenter cohort study on patients with unipolar, bipolar I and II disorders

Background: To estimate the prevalence of DSM-5 anxious distress specifier (ADS) in depressed patients with major depressive disorder (MDD) or bipolar I or II disorder (BD), and to compare socio-demographic and clinical characteristics, and response to naturalistic short-term treatment between ADS and non-ADS group. Methods: 241 outpatients with a major depressive episode (MDE) were consecutively recruited. Outcome were remission (HDRS21 total score < 7), response (≥50% reduction of baseline HDRS21) and improvement (CGI-i score ≤ 2) after 12 weeks of treatment sustained for 4 weeks. Results: ADS was more frequent in BD than in MDD (respectively, 66.9% and 51.2%, χ2 = 6.1, p = 0.013). Compared with those non-ADS, patients with ADS had more severe depressive (respectively, HDRS21 total score 20.0 ± 4.4 and 18.6 ± 3.9, t-test = 2.67, p = 0.008) and mania symptoms (respectively, Y-MRS total score 2.2 ± 2.9 and 1.3 ± 2.3, M–W-test = 2.86; p = 0.004) at intake, a higher rate of BD family history (respectively, 35.2% and 22.2%, Χ2-test 10.4, p = 0.004) and more previous hypomanic episodes (respectively, (median (range) 0 (0–20) and 0 (0–15), MW-test = 2.39 p = 0.017). In the MDD group, patients with ADS had higher scores on hyperthymic temperament and mania symptoms (Y-MRS total score (median (range) 2.2 (0–26) and 0 (0–11), respectively, M–W test 2.071, p = 0.038). ADS and no-ADS patients did not significantly differ on outcome measures. Limitations: The observational nature of the study and the absence of blinding in outcome assessment. Conclusions: ADS is the most common DSM-5 specifier for MDE, is more frequent in BD and need a personalized treatment with moderate use of antidepressants, mostly tricyclic.