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ADHD: An Australian Perspective Dr Craig Andrews Child Psychiatrist The Speaker • I work in Government Child and Adolescent Community Mental Health Services (CAMHS) in three different Local Government districts of Sydney • I am part of a Multi-disciplinary team (MDT) of Doctors, Psychologists, and Nurses • I have treated several hundred children with ADHD What is ADHD? • Attention Deficit Hyperactivity Disorder is a neurodevelopmental disorder • It is a disorder characterised by signs and symptoms of inattention (i.e disorganisation and lack of persistence), hyperactivity (i.e excess of movements), and impulsivity (i.e acting without reflecting) • Detailed clinical assessment of the child and parents is required to differentiate ADHD from other disorders which can also have some of the same signs and symptoms Clinical Example • A year old boy from an intact and functioning middle class family • He presented with academic and social failure and exclusion from his private school where supports had been applied as available • His parents blamed his inattention, hyperactivity, impulsivity, defiance and anxiety problems on the school environment • His problems were replicated in his new government school, and his parents were now prepared to consider he may have ADHD • • • • • • He was unconcerned and insightless into his behaviours His parents were despairing and defensive His clinical assessment was consistent with ADHD, and Oppositional Defiant Disorder (ODD) The following disorders were screened for and excluded Depression, Anxiety, Development (e.g Autism), Intelligence and Learning, Attachment, Trauma, and Speech and Language Corroborative history from his current and past class teachers was consistent with ADHD and ODD Connor’s rating scales of his behaviours completed by his teacher and his parents were in the clinical range for both ADHD and ODD • He had an excellent response to immediate release Methylphenidate mg/kg in divided doses with no significant side effects • He was able to attend normally in class for the first time • His parents were very grateful that their child was now functioning at school • He was switched to a long acting formulation of Methylphenidate for convenience and enhanced compliance, increased privacy (and reduced stigma) with no school time dosing, and diversion risk reduction • Parents declined Behavioural Parent training with team psychologist Research findings • ADHD is one of the best-researched disorders in medicine • It is a valid neurobiological condition that causes significant impairment • It is one of the most common childhood psychiatric conditions (7.8% lifetime childhood diagnosis in a USA National Survey 2003) • The principal cause is genetic; 76% heritability in review of 20 independent twin studies • Genome scans suggest many genes are involved • The non genetic causes are neurobiological; they include perinatal stress, low birth weight, traumatic brain injury, maternal smoking in pregnancy, and extreme early environmental deprivation • Large scale clinical trials over years have proven the efficacy of drug treatments • The Multimodal Treatment of ADHD (MTA) study demonstrated greater efficacy of medication compared to psychosocial treatment alone (e.g behaviour therapy) Drug treatments • The Stimulants (Methylphenidate and Dexamphetamine) are highly efficacious treatments for ADHD In double blind placebocontrolled trials 65-75% subjects respond compared to 4-30% on placebo Effect size of 1.0 • 44% of subjects respond preferentially to either Methylphenidate or Dexamphetamine, hence both are often trialled • Many stimulant non responders respond to Atomoxetine (a noradrenergic reuptake inhibitor) which has an effect size of 0.62 • Clonidine is an alpha2-adrenergic agonist commonly used to treat sleep disturbance in ADHD, or co-morbid tics It only has a small effect size when used alone as an ADHD treatment • Atypical Anti-psychotics such as Risperidone are occasionally used as adjuvant treatments for severe cases, especially for severe aggression Drug side effects • Stimulants - include appetite decrease, weight loss, insomnia, headache Occasionally cause tics and emotional lability • Stimulants not - increase rate of tics relative to placebo; induce aggression; increase risk of sudden death (but if significant pre-existing heart disease consult cardiologist); lead to substance abuse (they reduce risk of this) • Stimulants can cause – clinically insignificant growth retardation (need to monitor height and weight); small increase in blood pressure (monitor) • Atomoxetine - usually transient side effects, include gastrointestinal distress, sedation and decreased appetite No evidence causes hepatotoxicity Very small increase in risk of suicidal ideation without evidence this leads to completed suicide • Clonidine – monitor pulse and blood pressure; avoid abrupt discontinuation Follow up treatment • Review to monthly once stable • Monitor growth on normative growth chart, blood pressure, side effects, efficacy of dose, school reports of behaviour and academic progress • Monitor for emergence of co-morbidity, e.g anxiety, depression • Periodically trial off medication to see if still required at a time of low stress, e.g annually Psychosocial treatments • Psycho-education is helpful in all cases • Patients with suboptimal response to medication, comorbid disorders (e.g anxiety), and stress in family life benefit from psychosocial intervention • The psychosocial intervention needs to be individualised to the patient and their family • For children aged less than 12 years of age Parentadministered behavioural modification training (e.g Positive Parenting Program; 1,2,3 Magic) assists Parents to manage specific problem behaviours and repair strained parent-child relationships • Social skills training – there is little evidence that supports its use Parents are usually advised to involve their children in structured community children’s groups where skills can be learnt in vivo under adult supervision, e.g religious youth groups, sports teams • Cognitive Behavioural therapy can assist co-morbid anxiety and depression Educational interventions • Neuropsychiatric and intellectual assessment is made where clinically indicated • Behaviourally based classroom interventions administered by teachers and aides, e.g sit child at the front of the class • Referral to specialist educational settings for behaviourally disturbed and/or emotionally disturbed children is common in cases referred for Child Psychiatric evaluation Other therapies • • • • • • • • • • • There is no evidence to support use of :- elimination or restriction diets - diet supplementation with essential fatty acids - behavioural optometry - chiropractic treatment - biofeedback (including neurofeedback) - homeopathy - acupuncture - physical activity - massage - sensory integration therapies Monitoring of use in Australia • • • • • • Stimulants are controlled drugs that require a specially authorised prescription The Ministry of Health grants prescription rights on application Generally prescribers are Paediatricians and Child Psychiatrists Prescribers are required to trial immediate release Methyphenidate prior to trialling long acting formulations Atomoxetine can only be prescribed where stimulants are ineffective, not tolerated due to weight loss or worsening of tics, or where risk of stimulant abuse or diversion is high Prescribers must submit monthly notification of stimulant prescriptions made identifying the patients name, address, age, weight, and dosage used Individual patient application is required for treatment of children under the age of four, and above maximum recommended dose Use in children under the age of two is forbidden Diversion • Despite the above controls diversion of stimulants to users of illicit psychostimulants does occur • In a 2009 cross-sectional survey of 300 such users in Australia, 31% had used diverted prescribed immediate release stimulants • They usually took them for recreational use, but a minority were self medicating an undiagnosed and untreated ADHD Costs • The Government subsides the cost of medication for patients via a Pharmaceutical Benefits Scheme funded by a universal Medicare levy on all taxpayers • Approximate dispensed price for the Government in Australian $ for an average monthly dose (patients pay a lower subsidised price) • - Methylphenidate immediate release 30 mg daily $22 • - Methylphenidate sustained release 30 mg daily $52 • - Dexamphetamine 15 mg daily $18 • - Atomoxetine 40-60 mg daily $110 • - Clonidine 200 mcg daily $20 • The cost of medications can vary significantly by country for many reasons, e.g Government bargaining with drug companies Summary • ADHD is common neurodevelopmental disorder that causes significant impairment • There is a range of efficacious medications available to treat it, as well as a range of often helpful psychosocial and educational interventions • I find ADHD a satisfying disorder to treat as it is possible to quickly make a big difference in the lives of children and their families ... screened for and excluded Depression, Anxiety, Development (e.g Autism), Intelligence and Learning, Attachment, Trauma, and Speech and Language Corroborative history from his current and past class... was consistent with ADHD and ODD Connor’s rating scales of his behaviours completed by his teacher and his parents were in the clinical range for both ADHD and ODD • He had an excellent response... disturbance in ADHD, or co-morbid tics It only has a small effect size when used alone as an ADHD treatment • Atypical Anti-psychotics such as Risperidone are occasionally used as adjuvant treatments