Subject(s)
Antioxidants/therapeutic use , Melatonin/therapeutic use , Night Terrors/complications , Night Terrors/drug therapy , Somnambulism/complications , Somnambulism/drug therapy , Asperger Syndrome/complications , Child, Preschool , Humans , Male , Night Terrors/diagnosis , Severity of Illness IndexABSTRACT
Studies of the clinical correlates of the subtypes of Attention-Deficit/Hyperactivity Disorder (ADHD) have identified differences in the representation of age, gender, prevalence, comorbidity, and treatment. We report retrospective chart review data detailing the clinical characteristics of the Inattentive (IA) and Combined (C) subtypes of ADHD in 143 cases of ADHD-IA and 133 cases of ADHD-C. The children with ADHD-IA were older, more likely to be female, and had more comorbid internalizing disorders and learning disabilities. Individuals in the ADHD-IA group were two to five times as likely to have a referral for speech and language problems. The children with ADHD-IA were rated as having less overall functional impairment, but did have difficulty with academic achievement. Children with ADHD-IA were less likely to be treated with stimulants. One eighth of the children with ADHD-IA still had significant symptoms of hyperactivity/impulsivity, but did not meet the DSM-IV threshold for diagnosis of ADHD-Combined Type. The ADHD-IA subtype includes children with no hyperactivity and children who still manifest clinically significant hyperactive symptomatology but do not meet DSM-IV criteria for Combined Type. ADHD-IA children are often seen as having speech and language problems, and are less likely to receive medication treatment, but respond to medical treatment with improvement both in attention and residual hyperactive/impulsive symptoms.
Subject(s)
Attention Deficit Disorder with Hyperactivity/classification , Medical Records , Attention Deficit Disorder with Hyperactivity/drug therapy , Attention Deficit Disorder with Hyperactivity/epidemiology , Central Nervous System Stimulants/therapeutic use , Child , Comorbidity , Demography , Educational Status , Female , Humans , Language Disorders/epidemiology , Language Disorders/therapy , Learning Disabilities/epidemiology , Male , Prevalence , Remedial Teaching/methods , Severity of Illness Index , Speech Disorders/epidemiology , Speech Disorders/therapyABSTRACT
The initial molecular genetic studies of attention deficit hyperactivity disorder (ADHD) evaluated two candidate genes (DAT and DRD4) suggested by dopamine theories of this common disorder and its treatment with stimulant medication. The initial reports of weak associations with ADHD have been replicated by many (but not all) investigators, as is expected for genes with small effects. This literature is reviewed, along with emerging literature generated by active research groups investigating additional genes that might contribute to the genetic basis of this complex disorder.
Subject(s)
Attention Deficit Disorder with Hyperactivity/genetics , Genetic Predisposition to Disease , Membrane Glycoproteins , Membrane Transport Proteins/genetics , Nerve Tissue Proteins , Receptors, Dopamine D2/genetics , Attention Deficit Disorder with Hyperactivity/psychology , Child , Dopamine Plasma Membrane Transport Proteins , Genotype , Humans , Karyotyping , Membrane Transport Proteins/physiology , Receptors, Dopamine D2/physiology , Receptors, Dopamine D4 , Sequence Analysis, DNAABSTRACT
An association of the dopamine receptor D4 (DRD4) gene located on chromosome 11p15.5 and attention deficit/hyperactivity disorder (ADHD) has been demonstrated and replicated by multiple investigators. A specific allele [the 7-repeat of a 48-bp variable number of tandem repeats (VNTR) in exon 3] has been proposed as an etiological factor in attentional deficits manifested in some children diagnosed with this disorder. In the current study, we evaluated ADHD subgroups defined by the presence or absence of the 7-repeat allele of the DRD4 gene, using neuropsychological tests with reaction time measures designed to probe attentional networks with neuroanatomical foci in D4-rich brain regions. Despite the same severity of symptoms on parent and teacher ratings for the ADHD subgroups, the average reaction times of the 7-present subgroup showed normal speed and variability of response whereas the average reaction times of the 7-absent subgroup showed the expected abnormalities (slow and variable responses). This was opposite the primary prediction of the study. The 7-present subgroup seemed to be free of some of the neuropsychological abnormalities thought to characterize ADHD.
