Attention-deficit/hyperactivity disorder subtypes

Histamine produces its pharmacological actions by three subtypes of receptors the postsynaptic Hi and H2 receptors and the presynaptic H3 receptor. The H3 receptor is mainly located in the central nervous system (CNS), where it acts as an inhibitory autoreceptor in the central histaminergic neuronal pathways [176]. A number of therapeutic applications have been proposed for selective H3 receptor antagonists, including several CNS disorders such as Alzheimer s disease. Attention Deficit Hyperactivity Disorder, Schizophrenia, or for enhancing memory or obesity control. 

Waldman, I., Rowe, D., Abramowitz, A., Kozel, S., Mohr, J., Sherman, S., Cleveland, H., Sanders, M., Card, J., and Stever, C. (1998) Association and linkage of the dopamine transporter gene and attention-deficit hyperactivity disorder in children heterogeneity owing to diagnostic subtype and severity. Am J Hum Genet 63 1767-1776. 

Attention-deficit hyperactivity disorder is called hyperkinetic disorder in the ICD-10, which does not include the same subtypes as those in the DSM. According to the DSM-IV, ADHD is a broader definition than that given for HKD (hyperkinetic disorder) in the ICD-... 

While the "classic" manic is readily diagnosed, differentiating between diagnostic subtypes may be more difficult, especially when a seasonal pattern exists. Further disorders to rule out in the differential diagnosis include attention deficit hyperactivity disorder, schizophrenia, and schizoaffective disorder. 

Swanson JM, Kinsboume M, Nigg J, Lanphear B, Stefanatos GA, Volkow N, Taylor E, Casey BJ, Castellanos FX, Wadhwa PD. (2007) Etiologic subtypes of attention-deficit/hyperactivity disorder brain imaging, molecular genetic and environmental factors and the dopamine hypothesis. Neuropsychol Rev 17 39-59. 

ADHD, attention-deficit/hyperactivity disorder AV, atrioventricular BPH, benign prostatic hypertrophy CAD, coronary artery disease CHF, congestive heart failure COPD, chronic obstructive pulmonary disease CV, cardiovascular DA, dopamine Dl, subtype 1 dopamine receptor Epi, epinephrine FFA, free fatty acids 5-HT, serotonin ISA, intrinsic sympathomimetic activity MI, myocardial infarction NE, norepinephrine NO, nitric oxide PVR, peripheral vascular resistance. 

Sagvolden T., Johansen E. B., Aase H. and RusseU V. A. 2005a. A dynamic developmental theory of attention-deficit/hyperactivity disorder (ADHD) predominantly hyperactive/impulsive and combined subtypes. Behav. Brain Sci. 28 397-419... 

Analysis of structured psychiatric interviews makes it possible to identify different subtypes of the disorder, depending on the prevalence (and persistence for at least 6 months) of different symptoms (9 for the attention deficit variant and 9 for the hyperactive variant) (i) ADHD, combined type subtype (6/9 or more inattention symptoms and 6/9 or more hyperactivity/impulsiv-ity symptoms) (ii) ADHD, predominantly inattentive type subtype (6/9 or more inattention symptoms, but fewer than 6/9 hyperactivity/impulsivity symptoms) (iii) ADHD, predominantly hyperactive-impulsive type sub-type (6/9 or more hyperactivity-impulsivity symptoms, but fewer than 6/9 inattention symptoms). The minimum score for a child to be considered to be affected with ADHD is therefore 6/9 for both ADHD, predominantly inattentive type and ADHD, predominantly hyperactive-impulsive type subtypes, and at least 12/18 for the ADHD, combined type subtype. 

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