• Mood Lability
• Neurodevelopmental Disorders
• ADHD
• Emotional Dysregulation
• Bipolar Disorders

Background: Attention Deficit/Hyperactivity Disorder (ADHD) in adulthood have an heterogeneous and atypical presentation, notably with less externalizing and hyperactive symptoms and with a higher rate of psychiatric comorbidities. A symptomatological dimension that is also frequently associated in adult ADHD patients is the Emotional Dysregulation (ED), often with low frustration tolerance, impulsivity, irritability and affect and mood lability. Although it has long been recognized that many individuals with ADHD also have difficulties with emotion regulation, no consensus has been reached on how to conceptualize this clinically challenging domain. There are yet limited investigation into this aspect on the clinical picture of the disorder and it is discussed whether symptoms of ED could add a better description of the psychopathology of ADHD and an additional core symptom. The aim of this study is to explore the correlates of the presence of low and high level of ED in a sample of adult ADHD patients and its relationship with clinical, temperamental characteristics and other psychiatric comorbidities.
Method: Forty adult ADHD patients were enrolled in this study and all patients were assessed using the Diagnostic Interview for ADHD in Adults (DIVA 2.0), the Structured Clinical Interview for DSM-IV Axis I and II Disorders (SCID I/II), the brief Temperament Evaluation of Memphis, Pisa, Paris and San Diego–M (brief TEMPS-M), the Reactivity Intensity Polarity Stability Questionnaire (RIPoSt), the Semi-structured Interview for Mood Disorders (SIMD-R), the Barratt Impulsiveness Scale (BIS-11), the Adult Self-Report Scale (ASRS-v 1.1), the Global Assessment of Functioning (GAF) and the Functioning Assessment Short Test (FAST). We divided the sample into two groups using the RIPoSt mean score: one group with Low-Emotional Dysregulation (L-ED) and the second group with High-Emotional Dysregulation (H-ED).
Results: The multivariate linear regression analysis, showed that the variables mostly associated with the RIPoSt Total score (R-Tot) (higher ED) were Cyclothymic Temperament (p<0.000), Borderline Personality Disorder (p<0.003), FAST total score (p<0.001), Irritable Temperament (p<0.003), Anxious Temperament (p<0.011) and FAST Leisure subscale (p<0.040). Considering the RIPoSt subscale, the linear regression analysis showed that the variables mostly associated were the affective temperaments and some FAST subscales. Comparing the two groups we found that the mean score of ASRS (p<0.006), the mean score of the Dysthymic (p<0.010), Cyclothymic (p<0.000), Irritable (p<0.000) and Anxious temperamental subscale (p<0.000) of the briefTEMPS-M, the total score of the BIS scale (p<0.013) and of the BIS Attentional subscale (p<0.000) were statistically significant higher in patients with H-ED. Among other psychiatric disorders, The Bipolar Disorder-II (BD-II) (p<0.01), Cyclothymia (p<0.03) and Borderline Personality Disorder (BPD) (p<0.03) were significantly most associated in ADHD patient with H-ED.
Conclusions: The group of ADHD patients with H-ED showed a significant higher impulsiveness, a closer relationships with bipolar and personality disorder (Cyclothymia, BD-II, BPD) and a higher prevalence of Cyclothymic, Irritable, Anxious and Dysthymic Temperaments, compared to the patients of the L-ED group. Our results suggested that adult ADHD with high ED could represent a specific subgroup of patients with a higher severity of ADHD symptoms and a higher prevalence of affective disorders, configuring a new subtype of neurodevelopmental disorder. As reported in literature, we may hypothesize that the strong association and co-occurrence between BD, BPD and ADHD, it could depends on a shared common neurobiological basis between these supposedly distinct disorders and that the ED may represent the shared core dimension, with a key role in etiopathogenesis of disorders with affective instability.