The impact of cyclothymic temperament in adult ADHD

Abstract

Attention-Deficit/Hyperactivity Disorder (ADHD) is a prevalent neurodevelopmental disorder in children and adults. Many ADHD patients experience affective symptoms that resemble the cyclothymic temperament trait, which is suggested to be a part of the bipolar spectrum. However, the relationship between adult ADHD and cyclothymic temperament has never been systematically studied. A sample of 586 clinically diagnosed Norwegian adult ADHD patients and 721 population derived controls responded to the 21-item cyclothymic subscale of the Temperament Evaluation of Memphis, Pisa, Paris and San Diego auto-questionnaire (TEMPS-A). Self-reported data on psychiatric symptoms, comorbidity, educational and occupational level, and known comorbidity in family members, including bipolar disorder, was also obtained. The mean TEMPS-A scores were 13.0 for patients and 4.6 for controls (p<0.001), and 71% of the patients compared to 13% of the controls were classified as having a cyclothymic temperament (TEMPS score ≥11 points). Among ADHD patients, cyclothymic temperament was strongly associated with more childhood and adult ADHD symptoms, lower educational and occupational achievements and increased psychiatric comorbidity, including bipolar disorder (10%). In addition, 49% screened positive on the Mood Disorder Questionnaire. Although the cyclothymic TEMPS-A scale has been used in clinical settings in Norway for many years, it has not yet been officially validated. Cyclothymic temperament is highly prevalent in adults with ADHD, and this characterises a subgroup of more psychiatrically impaired individuals, possibly reflecting an underlying affective instability with a pathophysiology closer to the bipolar spectrum disorders.