Removal of pervasive developmental disorder (PDD) from the exclusion criteria
ADHD is one of the most frequent comorbid diagnosis in patients with PDD/ASD [11], and there is some evidence of genetic overlap between the two disorders [10]. Strictly applying the DSM-IV criteria may have prevented pharmacological treatment of some children with ASD and comorbid symptoms of ADHD who could have benefitted from this. Allowing for a diagnosis of ADHD with comorbid ASD may increase the prevalence of ADHD slightly
Other changes in the DSM-5 proposal
The proposal highlights that whenever possible information on symptoms and impairment should be obtained from two different informants, preferably a parent and teacher in the case of children and a third party/significant other in cases of adults. This is already a part of the text on ADHD in DSM-IV, but the Workgroup is concerned that clinicians tend to not pay sufficient attention to this requirement. Using multiple informants is more costly and time consuming, hence the Workgroup decided to recommend this rather than making it a requirement for the diagnosis
In addition, the Workgroup still considers lowering the cut-off for adults, i.e., change the threshold of symptoms required for a diagnosis. The Workgroup also plans to include recommendations for severity criteria for ADHD, although no suggestion for this has been published or made available online for comments as of yet (September 2012).
Possible impact of all proposed changes
Overall, the most important decision by the Workgroup was to retain the exact wording of each of the 18 symptoms, as a reformulation of the core symptoms would have had huge clinical and scientific impacts. The proposal will move ADHD away from being a disorder in children into being a neurodevelopmental disorder with a childhood onset. This corresponds very well with the overwhelming evidence of ADHD as a lifelong impairing condition and the new examples form a uniform basis for applying the diagnostic criteria on adults. Several rating scales and diagnostic interviews have rephrased the 18 DSM-IV diagnostic criterion into adult versions, but not in a uniform or coordinated way. DSM-5 will specify how these symptoms should be translated into difficulties in an adult everyday life. However, the majority of the suggested changes will have a tendency to increase the prevalence of ADHD, especially in adults and adolescents, but may be also in children.
International and national guidelines
Various guidelines for assessment and treatment of children and adolescents with ADHD have been published over the last decade, based on the diagnostic criteria in DSM-IV. The American Academy for Child and Adolescent Psychiatry (AACAP) has published several practice parameters [6, 15], and the European network for hyperkinetic disorders (EUNETHYDIS) has published European clinical guidelines [17]. The National Institute for Health and Clinical Excellence, NICE, has not only made very thorough reviews of the scientific literature and published a number of guidelines for clinicians on both assessment and treatment of children, adolescents, and adults [14], but also guidelines for patients and caregivers and suggestions for organization of clinics and implementation of the guidelines. Several European countries have published national guidelines (for instance in Germany [5, 9] and Denmark [18, 19]).