Differentiating Bipolar Disorder–Not Otherwise Specified and Severe Mood Dysregulation

Abstract

Objective Bipolar Disorder–Not Otherwise Specified (BP-NOS) and Severe Mood Dysregulation (SMD) are severe mood disorders that were both defined to address questions about the diagnosis of bipolar disorder (BD) in youth. SMD and BP-NOS are distinct phenotypes that differ in clinical presentation and longitudinal course. The purpose of this review is to inform clinicians about the clinical features of the two phenotypes and about the research literature distinguishing them. Method We review the literature on SMD as studied in the National Institute of Mental Health Intramural Research Program and on BP-NOS in youth. For BP-NOS, we focus on the phenotype defined in the Course of Bipolar Youth (COBY) study, since this has received the most study. Results SMD is characterized by impairing, chronic irritability without distinct manic episodes. Most commonly, BP-NOS is characterized by manic, mixed or hypomanic episodes that are too short to meet DSM-IV-TR duration criterion. Research provides strong, albeit suggestive, evidence that SMD is not a form of BD; the most convincing evidence are longitudinal data indicating that youth with SMD are not at high risk to develop BD as they age. The BP-NOS phenotype appears to be on a diagnostic continuum with BD type I and type II. BP-NOS and BD- type I subjects have similar symptom and family history profiles, and youth with BP-NOS are at high risk to develop BD as they age. Currently, little research guides treatment for either phenotype. Conclusions Pressing research needs include identifying effective treatments for these phenotypes, ascertaining biomarkers that predict conversion from BP-NOS to BD, elucidating associations between SMD and other disorders, and defining the neural circuitry mediating each condition.

Disruptive Mood Dysregulation Disorder and Bipolar Disorder Not Otherwise Specified: Fraternal or Identical Twins?

“…Youth with DMDD were similar to those with BP-NOS on most clinical factors, including: Number of diagnoses; number of medications; likelihood of prior hospitalization; comorbid ADHD, anxiety disorders, pervasive developmental disorders, elimination disorders, and psychosis; global impairment; PGBI-10M; and depressive and anxiety symptom severity. Only disruptive behavior disorders were more common in children with DMDD, consistent with prior research (Stringaris et al 2010;Axelson et al 2012;Towbin et al 2013). Irritability on the parentreported Irritability Scale was nominally higher at baseline, but to a nonsignificant degree, for the DMDD group compared with the BP-NOS group, but then decreased more rapidly over time.…”

“…The Family History Screen (Weissman et al 2000) was completed to collect information on parental psychiatric disorders. In addition to presence or absence of manic symptoms, parents were considered to have a probable bipolar disorder if they had elated mood plus three additional symptoms of mania or irritable mood plus four additional symptoms of mania.…”

DSM-5: Disruptive mood dysregulation disorder

“…In contrast, youth meeting criteria for bipolar disorder not otherwise specified type (i.e., those who do not meet duration criteria for bipolar disorder but have significant periods of manic or hypomanic symptoms and other bipolar disorder symptoms) do seem to be at very high risk for full bipolar disorder over time (Towbin et al, 2013). Hence, distinguishing youth with DMDD from those with unspecified bipolar disorder has important clinical implications as treatment strategies for the two are likely to be different.…”

Callous-Unemotional Traits, Proactive Aggression, and Treatment Outcomes of Aggressive Children With Attention-Deficit/Hyperactivity Disorder

“…Reactive aggression is a frequent complication of psychiatric disorders that raise susceptibility to negative affect, especially irritability, that impair impulse control, or that distort one’s detection and appraisal of threat. 12–19 …”