ADHD
ADHD means Attention Deficit Hyperactivity Disorder. ADHD is a neuropsychiatric condition affecting children, adolescents, and adult, characterized by a pattern of diminished sustained attention, and increased impulsivity or hyperactivity. ADHD affects up to 5 to 8 percent of school-age children, with 60 to 85 percent of those diagnosed as children continuing to meet criteria for the disorder in adolescence, and up to 60 percent continuing to be symptomatic into adulthood. Children, adolescents, and adults with ADHD often have significant impairment in academic functioning as well as in social and interpersonal situations. ADHD is frequently associated with comorbid disorders, including learning disorders, anxiety disorders, mood disorders, and disruptive behavior disorders.
ETIOLOGY
Cause of ADHD is mainly genetic, with a heritability of approximately 75 percent. ADHD symptoms are the product of complex interactions of neuroanatomical and neurochemical systems.
1. Genetic Factors:
Family studies shows an increased concordance in monozygotic compared to dizygotic twins, as well as a marked increased risk of two to eight times for siblings as well as parents of an ADHD child, compared to the general population. Cook and colleagues have found an association of the dopamine transporter gene (DAT1) with ADHD. Family studies and population-based studies have found an association between the dopamine four receptor seven-repeat allele (DRD4) gene and ADHD.
2. Neurochemical Factors:
Dopamine & Norepinephrine are the 2 Neurochemicals primarily implicated as dysfunctional in ADHD. Prefrontal cortex & Locus ceruleus areas of the brain have been implicated based on its role in attention and regulation of impulse control.
3. Neurophysiologic Factors:
EEG studies in ADHD children and adolescents have found increased theta activity, especially in the frontal brain regions. Further studies of youth with ADHD have provided data showing elevated beta activity in their EEG studies.
4. Neuroanatomical Aspects:
MRI & PET studies suggests that populations of children with ADHD show evidence of both decreased volume and decreased activity in prefrontal regions, anterior cingulate, globus pallidus, caudate, thalamus, and cerebellum. PET scans have also shown that female adolescents with ADHD have globally lower glucose metabolism than both control female andmale adolescents without ADHD. One theory postulate that the frontal lobes in children with ADHD do not adequately inhibit lower brain structures, an effect leading to disinhibition.
5. Developmental Factors:
Higher rates of ADHD are present in children who were born prematurely and whose mothers had infections during pregnancy.
6. Psychosocial Factors:
Severe chronic abuse, maltreatment, and neglect are associated with specific behavioral symptoms that overlap with ADHD, including poor attention and poor impulse control.
CLINICAL FEATURES
Symptoms are present before the age of 12; Usually starts before the age of 5. In school, children with ADHD may attack a test rapidly but may answer only the first two questions. They may be unable to wait to be called on in school and may respond before everyone else. Inappropriately blurts out answers. Cannot wait his turn. They have poor attention to detail & makes frequent mistakes. Cannot engage in activities requiring prolonged attention. Poor organizational skills, procrastinates from tasks requiring attention. Loses things. Fidgety/restless & cannot stay seated.
At home, caregivers cannot put them off for even a minute. They appear not to listen when spoken to. Impulsiveness and an inability to delay gratification are characteristic. Children with ADHD are often susceptible to accidents. Runs/climbs inappropriately. Cannot do things quietly (e.g., play), Inappropriately talkative. Interrupts others while they talk. The most cited characteristics of children with ADHD, in order of frequency, are hyperactivity, attention deficit (short attention span, distractibility, perseveration, failure to finish tasks, inattention, poor concentration), impulsivity (action before thought, abrupt shifts in activity,lack of organization, jumping up in class), memory and thinking deficits, specific learning disabilities, and speech and hearing deficits.
Associated features often include perceptual-motor impairment, emotional lability, and developmental coordination disorder. A significant percentage of children with ADHD show behavioral symptoms of aggression and defiance. School difficulties, both learning and behavioral, commonly exist with ADHD. Comorbid communication disorders or learning disorders that hamper the acquisition, retention, and display of knowledge complicate the course of ADHD.
DIAGNOSIS
A Psychiatrist can elicit inattention, impulsivity, and hyperactivity from a detailed history of a child’s early developmental patterns along with direct observation of the child, especially in situations that require sustained attention. Hyperactivity may be more severe in somesituations (e.g., school) and less marked in others (e.g., one-on-one interviews), and may be less evident in pleasant structured activities (sports). The diagnosis of ADHD requirespersistent, impairing symptoms of either hyperactivity/impulsivity or inattention in at least two different settings, like school and at home.
In school, children with ADHD often exhibit difficulties following instructions and require increased individualized attention from teachers. At home, children with ADHD frequently have difficulty complying with their parent’s directions and may need to be asked multiple times to complete relatively simple tasks. Children with ADHD typically act impulsively, are emotionally labile, explosive, lack focus, and are irritable. Children for whom hyperactivity is a predominant feature are more likely to be referred for treatment earlier than are children whose primary symptoms are attention deficit. Specific learning disorders in the areas of reading, arithmetic, language, and writing frequently occur in association with ADHD. School history and teacher’s reports are critical in evaluating whether a child’s difficulties in learning and school behavior are caused primarily by inattention or compromised understanding of the academic material. In addition to intellectual limitations, poor performance in school may result from maturational problems, social rejection, mood disorders, anxiety, or poor self-esteem due to learning disorders.
The mental status examination in a given child with ADHD who is aware of his or her impairment may reflect a demoralized or depressed mood. A child with ADHD may exhibit distractibility and perseveration and signs of visual-perceptual, auditory-perceptual, or language-based learning disorders. A neurologic examination may reveal visual, motor, perceptual, or auditory discriminatory immaturity or impairments without overt signs of visual or auditory disorders. Children with ADHD often have problems with motor coordination and difficulty copying age-appropriate figures, rapid alternating movements, right-left discrimination, ambidexterity, reflex asymmetries, and a variety of subtle non-focal neurologic signs (soft signs). A child with an unrecognized temporal lobe seizure focus may have behavior disturbances which can resemble those of ADHD.
DIFFERENTIAL DIAGNOSIS
ADHD must be differentiated from other disorders which may share similar symptoms.
A temperamental constellation of high activity level and short attention span, in the normal range for the child’s age, and without impairment, should be ruled out. Differentiating these temperamental characteristics from the cardinal symptoms of ADHD before the age of 3 years is difficult, mainly because of the overlapping features of an ordinarily immature nervous system and the emerging signs of visual-motor-perceptual impairments frequently seen in ADHD.
It is critical to evaluate for anxiety. Anxiety can accompany ADHD as a symptom or comorbid disorder, and anxiety can manifest with overactivity and easy distractibility.
It is not uncommon for a child with ADHD to become demoralized or, in some cases, to develop depressive symptoms in reaction to persistent frustration with academic difficulties and resulting in low self-esteem. But this must be differentiated from a primary depressive disorder and secondary academic, behavioural & social problems.
Mania and ADHD share many core features, such as excessive verbalization, motoric hyperactivity, and high levels of distractibility. Also, in children with mania, irritability seems to be more common than euphoria. Although mania and ADHD can coexist, children with bipolar I disorder exhibit more waxing and waning of symptoms than those with ADHD. Children with ADHD who had developed bipolar I disorder at 4-year follow-up had a higher co-occurrence of additional disorders and a higher family history of bipolar disorders and other mood disorders than children without bipolar disorder.
Frequently, oppositional defiant disorder, or conduct disorder and ADHD, may coexist. We must also distinguish specific learning disorders from ADHD; a child may be unable to read or do mathematics because of a learning disorder, rather than because of inattention. ADHD often coexists with one or more learning problems, including deficits in reading, mathematics, or written expression.
COURSE AND PROGNOSIS
The course of ADHD is variable. Symptoms persist into adolescence in 60 to 85 percent of cases, and into adult life in approximately 60 percent of cases. The remaining 40 percent of cases may remit at puberty or in early adulthood. In some cases, the hyperactivity may disappear, but the decreased attention span and impulse-control problems persist. Overactivity is usually the first symptom to remit, and distractibility is the last. ADHD does not usually remit during middle childhood. A family history of the disorder predicts persistence, as do adverse life events, and comorbidity with conduct symptoms, depression, and anxiety disorders. When remission occurs, it is usually between the ages of 12 and 20. After remission, the child can go on to have a productive adolescence and adult life, satisfying interpersonal relationships, and few significant sequelae. Most patients with the disorder, however, undergo partial remission and are vulnerable to antisocial behavior,substance use disorders, and mood disorders. Learning problems often continue throughout life.
In about 60 percent of cases, some symptoms persist into adulthood. Those who persist with the disorder may show diminished hyperactivity but remain impulsive and accidentprone. Children with ADHD whose symptoms persist into adolescence are at higher risk for developing conduct disorder. Children with both ADHD and conduct disorder are also at risk for developing substance use disorders. The development of substance use disorders among ADHD youth in adolescence appears to be more related to the presence of conduct disorder rather than to ADHD.
Most children with ADHD have some social difficulties. Socially dysfunctional children with ADHD have significantly higher rates of comorbid psychiatric disorders and experience more problems with behavior in school as well as with peers and family members. Overall, the outcome of ADHD in childhood seems to be related to the degree of persistent comorbid psychopathology, primarily conduct disorder, social disability, and chaotic family factors. For optimal outcomes, it is essential to ameliorate children’s social functioning, diminish aggression, and improve family situations as early as possible.
Laboratory Investigations
• TFT- Thyroid blood test to rule out hypothyroidism/hyperthyroidism
• Vitamin blood levels – B12, vitD3
• Blood & Urine Routines
• LFT & RFT
• EEG
• ECG
TREATMENT
Pharmacotherapy
Pharmacologic treatment is considered the first line of treatment for ADHD. CNS stimulants: Methylphenidate are the first choice of agents in that they have the highest efficacy with generally mild tolerable side effects. Nonstimulant medications approved by the FDA in the treatment of ADHD include atomoxetine, a norepinephrine uptake inhibitor. α-agonistsclonidine is also useful in treating ADHD. Antidepressants, such as bupropion, have been used with variable success in the treatment of ADHD. Modafinil has also been tried with some success. Venlafaxine & Fluoxetine has been used with success in patients with comorbid depression & anxiety
Psychosocial Interventions
Psychosocial interventions for children with ADHD include psychoeducation, academic organization skills remediation, parent training, behavior modification in the classroom and at home, CBT, and social skills training. Evaluation and treatment of coexisting learning disorders or additional psychiatric disorders are essential. When we help children structure their environment, their anxiety diminishes. Parents and teachers should work together to develop concrete expectations for the child, and a system of rewards when the child meets these expectations. Children with ADHD do not benefit from being exempted from the requirements, expectations, and planning applicable to other children.
Reference:
1. Oxford Textbook of Psychiatry
2. Kaplan & Sadock’s Comprehensive Textbook of Psychiatry
3. The ICD-10: Classification of Mental and Behavioural Disorders
4. Diagnostic and Statistical Manual of Mental Disorders (DSM–5)
5. https://www.ncbi.nlm.nih.gov/pmc/
Self-Assessment
