Evaluation and Treatment of Children with Attention Deficit Disorders
Sally E. Shaywitz MD1
Bennett A. Shaywitz MD2
1 Director, Learning Disorders Unit; Associate Professor of Pediatrics, Yale Child Study Center and Yale University School of Medicine, 333 Cedar St, New Haven, CT 06510
2 Director, Pediatric Neurology; Associate Professor of Pediatrics and Neurology, Yale Child Study Center and Yale University School of Medicine, New Haven, Connecticut
Attention deficit disorder (ADD) is the most common neurobehavioral disorder in the pediatric age group: it affects 5% to 10% of the school-age population, with boys outnumbering girls 3 or 4:1. The development of research diagnostic criteria (RDC), based upon the Diagnostic and Statistical Manual of Mental Disorders (DSM III), represents a significant theoretical and practical advance for the reliable and valid diagnosis of ADD. Ascertainment of such specific criteria for inclusion and exclusion of the diagnosis are dependent upon the acquisition of complete and pertinent historical information, information that must be obtained from a number of sources, including the child, his/her parents, and the school. In addition to the usual clinical history, such information is most practically obtained via questionnaires which serve to systematize and simplify the acquisition of historical information.
Although the routine neurologic examination is usually not helpful in discriminating children with ADD, examination for neuromaturational signs (NMS or "soft signs") such as laterality, choreiform movements, mirror on overflow phenomena, diadochokinesis, and performance on a variety of fine and gross motor tasks frequently reveals abnormalities. Routine and even specialized laboratory tests (CT, karyotype) generally are not useful, but good management demands an accurate assessment of both intelligence and achievement, using individually administered tests.
Management of the child with ADD should focus on the optimization of an educational plan, and necessitates an awareness of such general educational approaches as self-contained classrooms, structured classroom settings, removal from distracting stimuli, and optimal timing and specific recommendations for deciding upon curriculum changes. At times, psychotherapy and other behavioral therapies are indicated. When pharmacotherapy is used, the physician must determine not only the optimal time to initiate pharmacothenapy, but the particular symptoms he hopes to ameliorate. Dosage is dictated by an understanding of the pharmacology of the particular agent chosen. The stimulant drugs have proven to be the safest and most effective agents, and methylphenidate is the usual first choice. Recent investigations have clarified the pharmacokinetics of methylphenidate, and indicate an elimination half-life of two hours, with a time to peak blood levels after oral administration of 2.5 hours. A dose of 0.3 mg/kg is a safe and effective initial dose. If there is no response the drug can be increased in increments of 5 mg/d each week until a maximum dose of 0.6 mg/kg/d is achieved. Blood levels in children who have responded to methylphenidate average 8 to 10 ng/mL at 0.3 mg/kg and 20 to 30 ng/mL at a dose of 0.6 mg/kg. Use of the drug only during school days but not on weekends and during school vacations limits exposure and reduces the likelihood of growth suppression, one of the potential toxic effects of the drug. A more serious concern is the development of multiple tic syndrome (Gilles de la Tourette's syndrome) as a consequence of methylphenidate. The potential for this complication can be minimized by avoiding methylphenidate in any child with a significant family history of tics or Gilles de Ia Tourette's syndrome and eliminating the drug at the first sign of any tics.
