An Open-Label, Randomized Trial of Methylphenidate and Atomoxetine Treatment in Children with Attention-Deficit/Hyperactivity Disorder.

OBJECTIVE: The efficacy of both methylphenidate and atomoxetine has been established in placebo-controlled trials. The present study aimed to directly compare the efficacy of methylphenidate and atomoxetine in improving symptoms among children with attention-deficit/hyperactivity disorder (ADHD). METHODS: The study sample included 160 drug-naïve children and adolescents 7-16 years of age, with DSM-IV-defined ADHD, randomly assigned to osmotic-release oral system methylphenidate (OROS-methylphenidate) (n=80) and atomoxetine (n=80) in a 24 week, open-label, head-to-head clinical trial. The primary efficacy measure was the score of the ADHD Rating Scale-IV Parents Version: Investigator Administered and Scored (ADHD-RS-IV). The secondary efficacy measures included the Clinical Global Impressions-ADHD-Severity (CGI-ADHD-S) and Chinese Swanson, Nolan, and Pelham IV scale (SNAP-IV), based on the ratings of investigators, parents, teachers, and subjects. RESULTS: At week 24, mean changes in ADHD-RS-IV Inattention scores were 13.58 points (Cohen's d, -3.08) for OROS-methylphenidate and 12.65 points (Cohen's d, -3.05) for atomoxetine; and mean changes in ADHD-RS-IV Hyperactivity-Impulsivity scores were 10.16 points (Cohen's d, -1.75) for OROS-methylphenidate and 10.68 points (Cohen's d, -1.87) for atomoxetine. In terms of parent-, teacher-, and self-ratings on behavioral symptoms, both of the two treatment groups significantly decreased on the SNAP-IV scores at the end-point, with effect sizes ranging from 0.9 to 0.96 on the Inattention subscale and from 0.61 to 0.8 on the Hyperactivity/Impulsivity subscale for OROS-methylphenidate; and from 0.51 to 0.88 on the Inattention subscale and from 0.29 to 0.57 on the Hyperactivity/Impulsivity subscale for atomoxetine. No statistically significant differences between treatment groups were observed on the outcome measures. Vomiting, somnolence, and dizziness were reported more often for atomoxetine than for OROS-methylphenidate, whereas insomnia was reported more often for OROS-methylphenidate than for atomoxetine. CONCLUSIONS: After 24 weeks of treatment, OROS-methylphenidate and atomoxetine had comparable efficacy in reducing core ADHD symptoms in drug-naïve children and adolescents with ADHD.

Associations of symptoms and subtypes of attention-deficit hyperactivity disorder with visuospatial planning ability in youth.

Little is known about which ADHD core symptom or subtype is most associated with visuospatial planning deficit. This issue was investigated in a sample of 408 youths with current DSM-IV diagnosis of ADHD, and 332 youths without lifetime ADHD, aged 8-17 years (mean age 12.02±2.24). All the participants and their mothers were interviewed using the Chinese Kiddie Epidemiologic version of the Schedule for Affective Disorders and Schizophrenia to obtain information about ADHD symptoms and diagnosis and other psychiatric disorders. In addition to clinical assessments, the participants were assessed with the WISC-III and the Stocking of Cambridge task of the Cambridge Neuropsychological Test Automated Battery. Multi-level regression models were used for data analysis. The results showed that univariate analyses revealed that inattention, hyperactivity, and impulsivity were significantly associated with visuospatial planning, and the magnitude of such association was amplified with increased task difficulties. Only inattention independently predicted visuospatial planning in a model that included all three ADHD symptoms. After further controlling for comorbidity, age of assessment, treatment with methylphenidate, and Full-scale IQ, inattention was still independently associated with visuospatial planning indexed by mean moves needed to solve problems. In subtype comparison, participants with combined subtype and those with prominently inattentive subtype, rather than prominently hyperactivity/impulsivity subtype, had poorer visuospatial planning performance. Our findings indicate that inattention is independently associated with impaired visuospatial planning, and dimensional approach retains the important distinction among ADHD symptoms than subtype approach in understanding the neuropsychological functioning of ADHD.