ADHD and autism: differential diagnosis or overlapping traits? A selective review

• Published in: Attention deficit and hyperactivity disorders Vol. 4; no. 3; pp. 115 - 139
• Main Authors: Taurines, Regina, Schwenck, Christina, Westerwald, Eva, Sachse, Michael, Siniatchkin, Michael, Freitag, Christine
• Format: Journal Article
• Language: English
• Published: Vienna Springer Vienna 01.09.2012
• Subjects: Animals; Attention Deficit Disorder with Hyperactivity - diagnosis; Attention Deficit Disorder with Hyperactivity - drug therapy; Attention Deficit Disorder with Hyperactivity - epidemiology; Attention Deficit Disorder with Hyperactivity - genetics; Attention Deficit Disorder with Hyperactivity - therapy; Autistic Disorder - diagnosis; Autistic Disorder - drug therapy; Autistic Disorder - epidemiology; Autistic Disorder - genetics; Autistic Disorder - therapy; Behavior Therapy - methods; Central Nervous System Stimulants - therapeutic use; Comorbidity; Diagnosis, Differential; Genetic Predisposition to Disease - psychology; Humans; Medicine; Medicine & Public Health; Neuroimaging - psychology; Neuropsychological Tests; Proteomics - statistics & numerical data; Psychiatry; Review Article; Risk Factors; ADHD; Autism; Brain imaging; Risk factor; Proteomics; Genetics; Empathy; Reward
• ISSN: 1866-6116; 1866-6647; 1866-6647
• DOI: 10.1007/s12402-012-0086-2

According to DSM-IV TR and ICD-10, a diagnosis of autism or Asperger Syndrome precludes a diagnosis of attention-deficit/hyperactivity disorder (ADHD). However, despite the different conceptualization, population-based twin studies reported symptom overlap, and a recent epidemiologically based study reported a high rate of ADHD in autism and autism spectrum disorders (ASD). In the planned revision of the DSM-IV TR, dsm5 (www.dsm5.org), the diagnoses of autistic disorder and ADHD will not be mutually exclusive any longer. This provides the basis of more differentiated studies on overlap and distinction between both disorders. This review presents data on comorbidity rates and symptom overlap and discusses common and disorder-specific risk factors, including recent proteomic studies. Neuropsychological findings in the areas of attention, reward processing, and social cognition are then compared between both disorders, as these cognitive abilities show overlapping as well as specific impairment for one of both disorders. In addition, selective brain imaging findings are reported. Therapeutic options are summarized, and new approaches are discussed. The review concludes with a prospectus on open questions for research and clinical practice.