Could comorbid bipolar disorder account for a significant share of executive function deficits in adults with attention-deficit hyperactivity disorder?
Article first published online: 29 NOV 2013
© 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd
Volume 16, Issue 3, pages 270–276, May 2014
How to Cite
Could comorbid bipolar disorder account for a significant share of executive function deficits in adults with attention-deficit hyperactivity disorder? Bipolar Disord 2014: 16: 270–276. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd., , , , , , , , , , , , , .
- Issue published online: 5 MAY 2014
- Article first published online: 29 NOV 2013
- Manuscript Accepted: 1 AUG 2013
- Manuscript Received: 18 OCT 2012
- Conselho Nacional de Desenvolvimento Científico e Tecnológico
- Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul
- Hospital de Clínicas de Porto Alegre
- ADHD ;
- attention-deficit hyperactivity disorder;
- bipolar disorder;
- executive function;
- Wisconsin Card Sorting Test
The frequent comorbidity between attention-deficit hyperactivity disorder (ADHD) and bipolar disorder (BD) represents a challenge for disentangling specific impairments of each disorder in adulthood. Their functional impairments seem to be mediated by executive function deficits. However, little is known about the extent to which each executive function deficit might be disorder specific or explained by the comorbidity. The aim of the present study was to determine if comorbid BD could account for a significant share of executive function deficits when measured by the Wisconsin Card Sorting Test (WCST) in adults with ADHD.
Adult patients with ADHD and healthy subjects were evaluated in the ADHD outpatient Program at the Hospital de Clínicas de Porto Alegre. Psychiatric diagnoses were based on DSM-IV criteria. WCST scores were compared by multivariate analysis of covariance among three groups: ADHD with BD (n = 51), ADHD without BD (n = 278), and healthy subjects (n = 91).
When compared to patients without BD and healthy subjects, patients with ADHD and comorbid BD showed lower scores in total correct answers (p = 0.003); higher scores in total errors (p = 0.004) and non-perseverative errors (p = 0.002); and completed fewer categories (p = 0.009). Patients with ADHD without BD did not differ from healthy subjects.
WCST impairments among patients with ADHD seem to be to a large extent attributable to comorbid BD. Although other executive function deficits (e.g., in the inhibitory control domain) have been demonstrated to accompany ADHD, the present findings suggest that set-shifting deficits are strongly related to comorbid BD.