ADHD Definition/description A persistent pattern of inattention and/or hyperactivity-impulsivity that interferes with functioning or development. Epidemiology • More common in boys - However, may be under-diagnosed in girls Causes • • • • • • Genetics Concordance ADHD in homozygous twins is greater than in dizygotic twins Premature birth Low birth weight Alcohol or tobacco use in pregnancy Toxins Pathophysiology • • • • • • The main brain regions involved are: - Frontal lobe - Prefrontal lobe - Parietal lobe - Cerebellum Structural and functional alterations in front striatal circuitry activity Deformations of the basal ganglia - The more severe the deformations -> the more severe the symptoms Deficits in the anterior cingulate Decreased dopamine activity in the caudate and preliminary evidence in limbic regions Anatomical changes: - Reductions in bilateral frontal, parietal and temporal lobe grey matter volumes - Larger sizes in right frontal love and left temporal lobe Diagnosis • • • • • CBC Electrolyte levels Liver function tests - Before commending a stimulant therapy Thyroid function tests Imaging studies: - MRI • - SPECT Barkley Home Situations Questionnaire DSM V Criteria A. A persistent pattern of inattention and/or hyperactivity-impulsivity that interferes with functioning or development as characterised by 1 or 2: • Inattention: for 6 or more of the following for at least 6 months to a degree that is inconsistent with developmental level and that negatively impacts directly on social and academic/occupation situations: CALL FOR FrED - Careless mistakes - Attention difficulty - Listening problems - Losses things - Fails to finish tasks - Organisational difficulty - Reluctance to do tasks - Forgetful activities - Easily distracted • Hyperactivity and impulsivity: six or more of the following for at least 6 months that is inconsistent with developmental level and negatively impacts directly on social and academic/occupational activities: (RUN FIDGE) - Runs, climbs, restless - Uninhibited conversation - Not able to play quietly - Fidgets or squirms in seat - Interrupts or intrudes on others - Difficulty waiting for turn - Get going, acting as if driven by motor - Evacuates seat unexpectedly - Talks excessively B. Several inattentive of hyperactive-impulsive symptoms were present prior to the age of 12. C. Several inattentive or hyperactive-impulsive symptoms are present in two or more settings. D. There is clear evidence that the symptoms interfere with, or reduce the quality of social, academic or occupational functioning. E. Those symptoms do not occur exclusively during the course of schizophrenia or another psychotic disorder, dissociative disorder, personality disorder, substance intoxication or withdrawal. Treatment and Management • • • • • Medications: - Stimulants ➔First line ➔Most effective ➔E.g. methylphenidate, dextroamphetamine, dexmethylphenidate, lisdexamfetamine etc. ➔All have similar efficacy, but differ in dosing, duration of action and adverse effects. ➔Target the symptoms of impulsivity, distractibility, poor task adherence, hyperactivity, and lack of attention. ➔Usually taken in the morning and not at bedtime -> mainly because of insomnia and exception is methylphenidate. ➔ADRs: appetite suppression, insomnia, weight loss, headaches, mood effects (depression and irritability). ➔May worsen tics in children with underlying tic disorders. ➔Affects on growth in children is not clear. ➔May cause: psychosis, substance abuse. - SNRIs and atomoxetine (Strattera) -> second line - Tricyclic anti-depressants ➔Before using them obtain a base line ECG ➔Can affect cardiac conduction - Clonidine and guanfacine have been used with mixed reports of efficacy. Sudden deaths have been reported in children taking clonidine with methylphenidate at bedtime. ➔The aetiology of these deaths is unclear, and this remains a controversial topic. - Modafinil ➔3rd or 4th line Behavioural psychotherapy - Effective when used in combination with an effective medication regimen. - Can help diminish uncertain expectation and increase organisation. Cognitive therapy for adults Psychological interventions Diet: - Foods containing preservatives or food colouring or foods high in simple sugars may worsen ADHD. ➔Not confirmed.