Major Depressive Disorder with Mixed Features: Clinical Characteristics of Patients Entered in a Multiregional Study

There has been continued evidence that some patients with Major Depressive Disorder also experience symptoms that are below the diagnostic threshold for hypomania. Major depressive disorder (MDD) associated with subthreshold hypomanic symptoms (mixed features) has been identified as a distinct nosological entity in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5).  In a publication in the Progress in Neuro-Psychopharmacology and Biological Psychiatry, Dr. Steven Targum and Dr. Cara Pendergrass identified the predominant “manic” symptoms endorsed by patients with MDD with mixed features.

figure-1The study was done as part of the subject selection approval process for a clinical trial called RESOLVE 1: A randomized, 6-week, double-blind, placebo-controlled, flexible-dose, parallel group study of lurasidone for the treatment of major depressive disorder with mixed features ( NCT01421134).  Lurasidone was well-tolerated and significantly improved depressive symptoms, manic symptoms, and overall illness severity in patients.  A full description of the study design and treatment results recently has been reported by Suppes and colleagues in the American Journal of Psychiatry “Lurasidone for the Treatment of Major Depressive Disorder with Mixed Features: A Randomized, Double-Blind, Placebo-Controlled Study.”

In the examination of clinical characteristics, racing thoughts and increased talkativeness were identified as the two most prominent manic symptoms reported by over 60% of patients with a decreased need for sleep reported by over 40% of patients with MDD with “mixed” features. Data also revealed that irritability and distractibility were reported as often as increased talkativeness and flight of ideas and suggested that these symptoms definitely co-exist within the “mixed” depression patient population.  However, the DSM-5 criteria specifically exclude psychomotor agitation, irritable mood, and distractibility from the diagnostic criteria for the mixed features specifier stating that these symptoms may overlap with acute depression as part of a major depressive episode.  The authors concluded that a four- or five-symptom cluster characterized the manic presentation in the majority of patients diagnosed as having MDD with “mixed” features in this first placebo.

FULL CITATION: Major depressive disorder with subthreshold hypomania (mixed features): Clinical characteristics of patients entered in a multiregional, placebo-controlled study.Prog Neuropsychopharmacol Biol Psychiatry. 2016 Feb 22;68:9-14. doi: 10.1016/j.pnpbp.2016.02.007
JOURNAL: Progress in Neuropsychopharmacology & Biological Psychiatry
AUTHORS: Targum SD, Suppes T, Pendergrass JC, Lee S, Silva R, Cucchiaro J, Loebel A
YEAR: 2016 February 22