注意力不足過動症 Attention-deficit/hyperactivity disorder

Diagnostic criteria of DSM-V A. characterized by (1) and/or (2) 1. inattention: >= 6 of the following 9 s/s for more than 6 months that is inconsistent with developmental level and negatively impacts directly on social and academic/occupational activities a. often fails to give close attention to details or makes careless mistakes in schoolwork or other activities b. has difficulty sustaining attention in tasks or play activities c. does not seem to listen when spoken to directly d. does not follow through on instructions and fails to finish schoolwork, chores, or duties in the workplace

Diagnostic criteria of DSM-V 1. inattention e. had difficulty organizing tasks and activities f. often avoids, dislikes or is reluctant to engage in tasks that require sustained mental effort g. often loses things necessary for tasks or activities h. easily distracted by extraneous stimuli i. Forgetful in daily activities

Diagnostic criteria of DSM-V 2. hyperactivity and impulsivity: >= 6 s/s have persisted for at last 6 months that is inconsistent with developmental level and negatively impacts directly on social and academic/occupational activities a. often fidgets with or taps hands or feet or squirms in seat b. often leaves seat in situations when remaining seated is expected c. often runs about or climbs in situations where it is inappropriate d. often unable to play or engage in leisure activities quietly e. often on the go, acting as if driven by a motor

Diagnostic criteria of DSM-V 2. hyperactivity and impulsivity f. often talks excessively g. often blurts out an answer before a question had been completed h. often had difficulty waiting his or her turn i. Often interrupts or intrudes on others

Diagnostic criteria of DSM-V B. Symptoms were present prior to age 12 years C. Symptoms were present in 2 or more settings (eg. Home, school, with friends, in activities) D. Symptoms interfere with or reduce the quality of social, academic or occupational functioning. E. Exclude schizophrenia or other mental disorder (eg. Mood disorder, anxiety disorder, dissociative disorder, personality disorder, substance intoxication or withdraw)

Epidemiology Incidence: 2-20% of grade-school children in USA; 3-7% pre-pubertal elementary school children Boy>girl (2-9 : 1) Parents show a increased incidence of hyperkinesis, sociopathy, alcohol use or conversion disorder Siblings are at higher risk to have learning disorder and academic difficulty 1st degree relatives are at high risk to develop ADHD, disruptive behavior disorders, anxiety disorders, and depressive disorders.

Etiology Genetic factors Developmental factors: winter infection during the 1st trimester Brain damage: ADHD exhibit soft neurological signs at higher rates Neuro-chemical factors: noradrenergic system of the central system( locus ceruleus) and peripheral sympathetic system

Etiology Neurophysiological factors 1. EEG: increased beta band percentages decreased delta band percentage 2. CT scan: no consistent finding 3. PET: lower cerebral blood flow & metabolic rates in the frontal lobe area

Etiology Psychosocial factors: emotional deprivation stressful psychic events disruption of family equilibrium anxiety-inducing factors

Pathology and Lab. examination EEG &PET: decreased cerebral blood flow in the frontal regions Continuous performance task (CPT): errors of omission (poor attention) errors of commission (impulsivity)

Differential diagnosis Anxiety disorder mania Conduct disorder Learning disorder

Course and prognosis Symptoms persist into adolescence or adult life: 50% Overactivity is usually the 1st symptom to remit and distractibility is the last Remission is usually between ages of Most patients undergo partial remission, are vulnerable to antisocial behavior, substance use disorder & mood disorders. Learning problems often continue throughout life.

Course and prognosis ADHD adults: diminished hyperactivity remain impulsive and accident-prone lower in educational attainments at risk for developing conduct disorder & substance-related disorder Social difficulties

Pharmacologic Treatment 1. CNS stimulants: The 1st choice Two most commonly used agents in USA: (1) Dextroamphetamine: >= 3 years old (2) Methylphenidate: >= 6 years old

Stimulant medications Dopamine agonist Effective in up to ¾ children Common side effect: headache, stomache, nausea, insomnia, rebound effect MPH can exacerbate tic disorder, cause growth suppression (make up at drug free period) 75% children exhibited sig. improvement in school performance

Stimulant medications MTS(MPH transdermal system): mg/h Onset: one hour good for children who have difficulty swallowing pills patches releasing MPH continually Side effect: as oral form MPH

pharmacologic treatment 2. Non-stimulant medications Atomoxetine (strattera): selective inhibition of presynatic norepinephrine transporter Maximal plasma levels: 1-2 hours Half-life: 5 hours For children>=6 years old

Atomoxetine (strattera): Common side effects: Dimmished appetite Abd. Discomfort Dizziness Irritability Increase BP & HR

Atomoxetine (strattera): Metabolized by cytochrome P450 (CYP) 2D6 hepatic enzyme system Increase plasma concentration of Atomoxetine: 1. poor metabolizers 2. drugs inhibit CYP 2D6 (eg. fluxetine, paroxetine, quinidine)

Other drugs for ADHD Bupropion (Wellbutrin) Clonidine: ADHD with tic disorders Tricycline drugs: arrhythmia side effect Antipsychotic: for refractory hyperactivity in children and adolescents. Watch out side effect Modafinil (Provigil): CNS stimulant

Monitoring pharmacological treatment Workup before starting use of stimulant medications Physical examination: annually Pulse: quarterly Weight: quarterly Height: quarterly

Psychosocial interventions Social skill groups Training for parents Behavioral interventions at school & at home. Manage coexisting learning disorder or additional psychiatric disorders

ADHD in adults Utah criteria for adult ADHD I. retrospective childhood ADHD diagnosis ( by parent interview or reported by pt) II. 5 additional symptoms: inattentiveness, hyperactivity, mood lability, irritability and hot temper, impaired stress tolerance, disorganization, impulsivity III. Exclusions: severe depression, psychosis, severe personality disorder

treatment Fist line choice: CNS stimulant Positive response: increased attention span, decreased impulsiveness, improved mood

Questions 1. What is the incidence of ADHD of prepubertal elementary school children? a. 1% b. 3-7% c. 20% d.50% 2. What is the current hypothesis that ADHD is transmitted? a. infection b. drug induced c. genetic d. unknown 3. What are the core symptoms of ADHD? a. inattention b. mood c. substance abuse d. insomnia 4. What is the first choice of agents for ADHD children and adults? a. haldol b. halcion c. NSAID d.CNS stimulant 5. What is the percentage of ADHD symptoms persisting into adolescence or adult life? a. 10% b. 20% c. 30% d %

Answers % 2. genetic 3. inattention 4. CNS stimulant %