Cognitive heterogeneity in adult attention deficit/hyperactivity disorder: A systematic analysis of neuropsychological measurements.
Attention Deficit/Hyperactivity Disorder (ADHD) in childhood is associated with impaired functioning in multiple cognitive domains: executive functioning (EF), reward and timing. Similar impairments have been described for adults with persistent ADHD, but an extensive investigation of neuropsychological functioning in a large sample of adult patients is currently lacking. We systematically examined neuropsychological performance on tasks measuring EF, delay discounting, time estimation and response variability using univariate ANCOVA's comparing patients with persistent ADHD (N=133, 42% male, mean age 36) and healthy adults (N=132, 40% male, mean age 36). In addition, we tested which combination of variables provided the highest accuracy in predicting ADHD diagnosis. We also estimated for each individual the severity of neuropsychological dysfunctioning. Lastly, we investigated potential effects of stimulant medication and a history of comorbid major depressive disorder (MDD) on performance. Compared to healthy adults, patients with ADHD showed impaired EF, were more impulsive, and more variable in responding. However, effect sizes were small to moderate (range: 0.05-0.70) and 11% of patients did not show neuropsychological dysfunctioning. The best fitting model predicting ADHD included measures from distinct cognitive domains (82.1% specificity, 64.9% sensitivity). Furthermore, patients receiving stimulant medication or with a history of MDD were not distinctively impaired. To conclude, while adults with ADHD as a group are impaired on several cognitive domains, the results confirm that adult ADHD is neuropsychologically heterogeneous. This provides a starting point to investigate individual differences in terms of impaired cognitive pathways.
Department of Human Genetics, Radboud university medical center, Nijmegen, The Netherlands.|Donders Centre for Cognitive Neuroimaging, Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, The Netherlands.
Jeanette C
JC
Mostert
Department of Psychiatry, Donders Institute for Brain, Cognition and Behaviour, Radboud university medical center, Nijmegen, The Netherlands.
A Marten H
AMH
Onnink
Department of Human Genetics, Radboud university medical center, Nijmegen, The Netherlands.
Marieke
M
Klein
Department of Human Genetics, Radboud university medical center, Nijmegen, The Netherlands.|Department of Psychiatry, Donders Institute for Brain, Cognition and Behaviour, Radboud university medical center, Nijmegen, The Netherlands.
Janneke
J
Dammers
Department of Human Genetics, Radboud university medical center, Nijmegen, The Netherlands.
Anais
A
Harneit
Department of Human Genetics, Radboud university medical center, Nijmegen, The Netherlands.
Theresa
T
Schulten
Department of Human Genetics, Radboud university medical center, Nijmegen, The Netherlands.|Donders Centre for Cognitive Neuroimaging, Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, The Netherlands.
Kimm J E
KJE
van Hulzen
Department of Psychiatry, Donders Institute for Brain, Cognition and Behaviour, Radboud university medical center, Nijmegen, The Netherlands.
Cornelis C
CC
Kan
Karakter Child and Adolescent Psychiatry University Centre, Nijmegen, The Netherlands.
Dorine
D
Slaats-Willemse
Karakter Child and Adolescent Psychiatry University Centre, Nijmegen, The Netherlands.|Department of Cognitive Neurosciences, Donders Institute for Brain, Cognition and Behaviour, Radboud university medical center, Nijmegen, The Netherlands.
Jan K
JK
Buitelaar
Department of Human Genetics, Radboud university medical center, Nijmegen, The Netherlands.|Department of Psychiatry, Donders Institute for Brain, Cognition and Behaviour, Radboud university medical center, Nijmegen, The Netherlands.
Barbara
B
Franke
Department of Human Genetics, Radboud university medical center, Nijmegen, The Netherlands.
Martine
M
Hoogman
D000328:Adult; D001289:Attention Deficit Disorder with Hyperactivity / Q000150:complications / Q000175:diagnosis / Q000188:drug therapy / Q000523:psychology*; D000697:Central Nervous System Stimulants / Q000627:therapeutic use; D003071:Cognition; D015331:Cohort Studies; D015897:Comorbidity; D065786:Delay Discounting; D003865:Major Depressive Disorder / Q000150:complications; D056344:Executive Function; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008960:Models, Psychological; D009426:Netherlands; D009483:Neuropsychological Tests; D011569:Psychiatric Status Rating Scales; D012680:Sensitivity and Specificity; D013998:Time Perception; D055815:Young Adult
D000697:Central Nervous System Stimulants
Adult ADHD; Executive function; Heterogeneity; Neuropsychology; Reaction time variability; Reward