Attention-deficit hyperactivity disorder symptoms in a clinic sample of children and adolescents with pervasive developmental disorders.

OBJECTIVES: The aims of this systematic chart review were to determine the frequency of attention-deficit/hyperactivity disorder (ADHD) in a clinic sample of children and adolescents with autism spectrum disorders (ASD), to compare ADHD symptoms in children with Autistic Disorder, Asperger's Disorder, and pervasive developmental disorders-not otherwise specified (PDD-NOS), to compare ADHD symptoms in individuals with and without ADHD-related chief complaints, and to determine the correlation between ADHD Rating Scale (ADHD RS) scores and age. METHOD: This systematic chart review examined data from children and adolescents who were consecutively referred to a university-based autism psychopharmacology program. All individuals were diagnosed by semistructured interview for ASD and ADHD, and ADHD symptoms were assessed using ADHD RS scores. RESULTS: Of 83 children, 78% fulfilled Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV) criteria for ADHD and exceeded the 93rd percentile norm for the ADHD RS. Hyperactivity-impulsivity scores were significantly greater in individuals with autism than those with other ASDs. DSM-IV ADHD diagnosis was represented equally in individuals with and without ADHD as their chief complaints. ADHD RS hyperactivity-impulsivity and total scores were negatively correlated with age. CONCLUSION: ADHD symptoms are pervasive in clinically referred children and adolescents with ASD.

Effect of methylphenidate on executive functioning in adults with attention-deficit/hyperactivity disorder: normalization of behavior but not related brain activity.

BACKGROUND: We examined the effect of prolonged methylphenidate (MPH) treatment on the functional neuroanatomy of executive functioning in adult men with attention-deficit/hyperactivity disorder (ADHD). METHODS: Positron emission tomography with [(15)O] water measured alterations of regional cerebral blood flow (rCBF) during the Paced Auditory Serial Addition Task and a control task in 10 ADHD and 11 normal control men. Attention-deficit/hyperactivity disorder men were imaged unmedicated and after a clinically optimal dose of MPH for 3 weeks. RESULTS: Methylphenidate improved ADHD task performance, reduced rCBF in the prefrontal cortex (PFC), and increased rCBF in the right thalamus and precentral gyrus. Comparisons between the ADHD and normal control groups showed that normal control participants exhibited greater anterior cingulate cortex and temporal gyrus rCBF than ADHD participants under both conditions. Executive functioning was associated with greater subcortical (basal ganglia and cerebellar vermis) activation in the ADHD than normal control group under both conditions. CONCLUSIONS: Methylphenidate does not normalize task-related activity in ADHD. Task-related rCBF decreases in the PFC may be due to improved filtering out of task-irrelevant stimuli by way of MPH-mediated dopamine release in the PFC.

A positron emission tomography study of methylphenidate in adults with ADHD: alterations in resting blood flow and predicting treatment response.

A hallmark symptom of attention-deficit hyperactivity disorder (ADHD) is an excess of motoric behavior or hyperactivity. Methylphenidate (MPH) is known to reduce hyperactivity in individuals with ADHD. Yet little is known about how it alters neural activity and how this relates to its clinical effects. The goal of this study is to examine MPH-induced changes during resting brain metabolism, and to examine how these changes correlate with measures of behavioral response to the drug. Measures of regional cerebral blood flow (rCBF) using positron emission tomography (PET) were acquired at rest for ten adult subjects with ADHD during both an unmedicated state and after a 3-week period of chronic dosing with a clinically optimal dose of MPH. Compared with the on-MPH condition, the off-MPH condition was associated with relative increases in rCBF bilaterally in the precentral gyri, left caudate nucleus, and right claustrum. The on-MPH condition was associated with relative increases in rCBF in the cerebellar vermis. A correlational analysis measured the relation between rCBF in the off-medication condition to change in ADHD ratings between the off- and on-MPH condition to identify brain regions associated with treatment response. The degree of change in the ratings was negatively correlated with rCBF increases in the midbrain, cerebellar vermis, and the precentral and middle frontal gyri in the off-MPH condition. The majority of these brain regions are involved in the planning and execution of motor behavior. These data suggest that MPH modulates brain regions associated with motor function to achieve a reduction in ADHD symptoms.