Soo Churl Cho

Attention deficit hyperactivity symptoms and Internet addiction

Abstract  The objective of this study was to evaluate the relationship between attention deficit‐hyperactivity/impulsivity symptoms and Internet addiction. In total, 535 elementary school students (264 boys, 271 girls; mean age, 11.0 ± 1.0 years) were recruited. The presence or severity of Internet addiction was assessed by the Youngs Internet Addiction test. Parents and teachers of the children completed the DuPauls attention deficit hyperactivity disorder (ADHD) rating scale (ARS; Korean version, K‐ARS) and Child Behavior Checklists. Children with the highest and lowest quartiles in K‐ARS scores were defined to be in ADHD and non‐ADHD groups, respectively. Five children (0.9%) met criteria for a definite Internet addiction and 75 children (14.0%) met criteria for a probable Internet addiction. K‐ARS scores had significant positive correlations with Youngs Internet Addiction test scores. The Internet addiction group had higher total scores of K‐ARS and ADHD‐related subcategories in the Child Behavior Checklists than the non‐addiction group. The ADHD group had higher Internet addiction scores compared with the non‐ADHD group. Therefore, significant associations have been found between the level of ADHD symptoms and the severity of Internet addiction in children. In addition, current findings suggest that the presence of ADHD symptoms, both in inattention and hyperactivity‐impulsivity domains, may be one of the important risk factors for Internet addiction.

Depression and Internet Addiction in Adolescents

Background: The aim of the study was to evaluate the relationship between depression and Internet addiction among adolescents. Sampling and Method: A total of 452 Korean adolescents were studied. First, they were evaluated for their severity of Internet addiction with consideration of their behavioral characteristics and their primary purpose for computer use. Second, we investigated correlations between Internet addiction and depression, alcohol dependence and obsessive-compulsive symptoms. Third, the relationship between Internet addiction and biogenetic temperament as assessed by the Temperament and Character Inventory was evaluated. Results: Internet addiction was significantly associated with depressive symptoms and obsessive-compulsive symptoms. Regarding biogenetic temperament and character patterns, high harm avoidance, low self-directedness, low cooperativeness and high self-transcendence were correlated with Internet addiction. In multivariate analysis, among clinical symptoms depression was most closely related to Internet addiction, even after controlling for differences in biogenetic temperament. Conclusions: This study reveals a significant association between Internet addiction and depressive symptoms in adolescents. This association is supported by temperament profiles of the Internet addiction group. The data suggest the necessity of the evaluation of the potential underlying depression in the treatment of Internet-addicted adolescents.

Regional cerebral blood flow in children with attention deficit hyperactivity disorder: Comparison before and after methylphenidate treatment

Differences in brain activity of children with attention deficit hyperactivity disorder (ADHD) have been compared to normal healthy controls, suggesting neural correlates of cognitive/behavioral symptoms. Symptoms are improved with methylphenidate treatment but limited sources can be cited to show how brain activity in ADHD is altered after pharmacologic treatment. We investigated how long‐term oral medication of methylphenidate affects the resting regional cerebral blood flow (rCBF) in ADHD children, using single photon emission computerized tomography (SPECT). rCBF was decreased in the orbitofrontal cortex and middle temporal gyrus in the right hemisphere whereas it was increased in the dorsomedial prefrontal and somatosensory area bilaterally in drug‐naïve ADHD children compared to control child subjects. After treatment with methylphenidate, the extent of hyperperfusion in the somatosensory area was reduced and significant reduction of rCBF was found in the right striatum for the first time. Methylphenidate treatment also resulted in rCBF increase in superior prefrontal and reduction in ventral higher visual areas bilaterally. The results indicated that improving ADHD symptom after methylphenidate is associated with normalization of abnormally reduced orbitofrontal activity and abnormally increased somatosensory cortical activity. These changes were accompanied with reduced striatum activity lower than that of normal controls. These changes might be associated with improving ADHD to control attention and motor response to irrelevant environmental stimuli after methylphenidate treatment. Hum. Brain Mapp 24:157–164, 2005.

Atomoxetine versus methylphenidate in paediatric outpatients with attention deficit hyperactivity disorder: a randomized, double-blind comparison trial

Objective: To (i) test whether atomoxetine is non-inferior to methylphenidate in treating symptoms of attention deficit hyperactivity disorder (ADHD) in paediatric patients; and (ii) determine the tolerability of the two drugs. Method: This double-blind study was conducted in 6- to 16-year-old outpatients with ADHD (DSM-IV) in China, Korea and Mexico (January–October 2004). Patients were randomly assigned to once-daily atomoxetine (0.8–1.8 mg kg−1 day−1; n = 164) or twice-daily methylphenidate (0.2–0.6 mg kg−1 day−1; n = 166) for ∼8 weeks. Primary efficacy assessment was the comparison of response rates (≥40% reduction from baseline to end point in total score) on the Attention Deficit Hyperactivity Disorder Rating Scale-IV-Parent Version: Investigator-Administered and -Scored. Tolerability measures included, but were not limited to, the assessment of treatment-emergent adverse events (TEAEs) and weight. Results: Atomoxetine was non-inferior to methylphenidate in improving ADHD symptoms based on response rates (atomoxetine, 77.4%; methylphenidate, 81.5%; one-sided 95% lower confidence limit = −11.7%, p = 0.404). Treatment-emergent adverse effects experienced significantly more frequently in the atomoxetine group, compared with the methylphenidate group, included anorexia (37.2% vs. 25.3%; p = 0.024), nausea (20.1% vs. 10.2%; p = 0.014), somnolence (26.2% vs. 3.6%; p <0.001), dizziness (15.2% vs. 7.2%; p = 0.024) and vomiting (11.6% vs. 3.6%; p = 0.007), most of which were of mild or moderate severity. Atomoxetine-treated patients experienced a small but significantly greater mean weight loss from baseline to end point than methylphenidate-treated patients (−1.2 kg vs. −0.4 kg; p <0.001). Conclusions: This study suggests that atomoxetine is non-inferior to methylphenidate in the improvement of ADHD symptoms in paediatric outpatients. Although both of the drugs were well tolerated, atomoxetine was associated with a higher incidence of TEAEs than methylphenidate.

A multicenter, randomized, double-blind, placebo-controlled study of aripiprazole in children and adolescents with Tourette's disorder.

OBJECTIVE To examine the short-term efficacy and tolerability of aripiprazole for children and adolescents with Tourettes disorder. METHOD This 10-week multicenter, double-blind, randomized, placebo-controlled trial was conducted from August 2008 to April 2010. Children and adolescents (aged 6-18 years) with a DSM-IV diagnosis of Tourettes disorder and a Yale Global Tic Severity Scale total tic score of 22 or more were randomly assigned (1:1 ratio) to placebo or aripiprazole. The primary outcome measure was mean change from baseline in the total tic score on the Yale Global Tic Severity Scale (last observation carried forward). Assessments of safety and tolerability included spontaneously reported adverse events, extrapyramidal symptoms, serum prolactin level, metabolic variables, and other laboratory evaluations. RESULTS Of 61 subjects, 89% completed the study. Patients who received aripiprazole demonstrated a significant reduction from baseline to end of study on the mean (SD) total tic score of the Yale Global Tic Severity Scale compared to those who received placebo (-15.0 [8.4] and -9.6 [8.8], respectively, P=.0196). Response rate on the Tourettes Syndrome Clinical Global Impression-Improvement was 66% and 45% in the aripiprazole and placebo groups, respectively. Mean decrease in the Tourettes Syndrome Clinical Global Impression-Severity of Illness score was significantly different between the groups (P=.0321). In general, aripiprazole was well tolerated and there were no early discontinuations due to adverse events. The incidence of treatment-emergent adverse events between the groups was not significantly different (P=.7550). While aripiprazole decreased serum prolactin concentration (P<.0001), it increased mean body weight, body mass index, and waist circumference significantly (P=.0055, P=.0142, and P=.0270, respectively). CONCLUSIONS In comparison with placebo, aripiprazole was efficacious, generally tolerated and safe in the short-term treatment of children and adolescents with Tourettes disorder. TRIAL REGISTRATION ClinicalTrials.gov identifier:NCT00706589.

A preliminary study: novelty seeking, frontal executive function, and dopamine receptor (D2) TaqI A gene polymorphism in patients with methamphetamine dependence.

INTRODUCTION Dopamine receptor polymorphisms have been associated with specific patterns of novelty seeking (NS) temperamental nature and frontal executive function. In addition, carriers of dopamine receptor type 2 (DRD2)-TaqI A1 have been hypothesized to be potentially vulnerable to addictive behaviors. In the present study, the association between dopamine D2 polymorphisms, NS, and frontal executive function was studied. METHODS Thirty-seven methamphetamine (MA)-dependent subjects and 40 healthy comparison subjects participated in the current study. The severity of addiction, NS temperament, and frontal executive functions were measured using the Addiction Severity Index, the NS subscale in the Temperament and Character Inventory, and the Wisconsin Card Sorting Test, respectively. All subjects were genotyped with regard to DRD2-TaqI polymorphisms. RESULTS The prevalence of DRD2-TaqI A1 allele polymorphisms was greater in the MA-abuser group than in the comparison group. Patients with MA dependence also had higher NS characteristics and high scores in total trials, errors, and perseverative errors of the Wisconsin Card Sorting Test than comparison subjects. Within patients with MA dependence, the subgroup of DRD2-TaqI A1 carrier had greater NS scores relative to those without, whereas there was only a trend level of lower frontal executive function in the first subgroup. CONCLUSION In the present study, the MA-dependent patients with DRD2-TaqI A1 allele had significantly greater NS scores and lower frontal executive function with a trend level than those without. These preliminary results suggest that MA-dependent patients may have the possibility of genetic and biogenic vulnerability to MA.

Copy number variations associated with idiopathic autism identified by whole-genome microarray-based comparative genomic hybridization.

Objectives Autism spectrum disorder (ASD) has been thought to have strong genetic background, but major contributing genes or associated molecular–genetic pathways are yet to be identified. To explore the idiopathic ASD-associated copy number variations (CNVs), we conducted case–control study using whole-genome copy number analysis. Methods Whole-genome microarray-based comparative genomic hybridization was carried out on 28 children (24 boys and four girls) diagnosed as ASD and 62 Korean adults (45 males and 17 females) without any signs of abnormalities and family history of genetic disorders as normal controls. Fluorescence in-situ hybridization and capillary electrophoresis-single-strand conformational polymorphism were used for quantitative verification of the ASD-associated CNVs. Results Thirty-eight CNVs were identified. Among them, the distributions of copy number loss CNVs on 8p23.1 (odds ratio: 5.1, 95% confidence interval: 1.7–14.5, P=0.003) and on 17p11.2 (odds ratio: uncalculable because of zero cell, P=0.008) were found to be significantly different between ASD and control groups. DEFENSIN family occurs in a cluster at 8p23.1 region. Fluorescence in-situ hybridization and capillary electrophoresis-single-strand conformational polymorphism coherently showed reduced copy number of DEFENSIN in cases with 8p23.1 copy number loss CNV, which validated microarray-based comparative genomic hybridization results; but there are no known coding genes in the CNV on 17p11.2. Conclusion Our approach as well as results can help to elucidate the genetic mechanism of idiopathic ASD.

The relationship between temperament and character and psychopathology in community children with overweight.

ABSTRACT. This study investigated the relationship between temperament and character and psychopathology in at risk of overweight and overweight children. The Child Behavior Checklist (CBCL) and the Junior Temperament and Character Inventory (JTCI) questionnaires were administered to 453 children (10-12 years of age, 203 boys and 250 girls) in Kimpo, South Korea. Subjects were divided into three groups; (1)nonoverweight children (n = 345), (2) children at risk of overweight (n = 72), and (3) overweight children (n = 36). CBCL and the JTCI scores were compared among three groups. In addition, the relationships between subscales of the CBCL and the JTCI were evaluated. On the CBCL, overweight children had higher scores in social problems, delinquent problems, and total problems compared to nonoverweight children. Children at risk of overweight showed higher scores only in social problems compared to nonoverweight children. On the JTCI, lower persistence and tendency of higher novelty seeking was observed in overweight children compared to nonoverweight children. Persistence scores were negatively correlated with scores of delinquent problems, externalizing problems, and total problems in overweight children. Compared to nonoverweight and children at risk of overweight, overweight children had distinct patterns of temperament and character that were related to the specific psychopathology.

Association of the DAT1 polymorphism with attention deficit hyperactivity disorder (ADHD): a family-based approach.

The dopamine transporter gene (DAT1) is of particular interest in the genetic study of attention deficit hyperactivity disorder (ADHD), because psychostimulants interact directly with the dopamine transporter protein. Association between ADHD and the 10‐repeat allele of a 40 base pair (bp) variable number of tandem repeats (VNTR) polymorphism of DAT1 was first reported in 1995 [Cook et al. (1995); Am J Hum Genet 56:993–998]. Subsequently, several investigators have also confirmed this association, although others reported conflicting results. We analyzed the DAT1 polymorphism in a sample of 33 Korean probands with a Diagnostic and Statistical Manual of Mental Disorders version IV (DSM‐IV) diagnosis of ADHD and found evidence of increased transmission of the 10‐repeat allele using transmission disequilibrium test (TDT) (P = 0.001; OR = 7.88, CI = 2.20–28.29). These data support the role of DAT1 in ADHD susceptibility among Asian populations.

Association between PTGS2 polymorphism and autism spectrum disorders in Korean trios

Cyclooxygenase-2 (Cox-2) is an inducible enzyme involved in neuroplasticity and the neuropathology of the central nervous system. This study evaluated the relationship between autism spectrum disorders (ASDs) and polymorphisms of PTGS2 (the gene encoding Cox-2) with 151 Korean family trios including children with ASDs. We found that the A allele of rs2745557 was preferentially transmitted in ASDs (p < 0.01) and that the GAAA haplotype was significantly associated with ASDs (p < 0.01). We also observed statistically significant associations between each genotype and the specific symptom domain scores of ADOS and ADI-R, including communication, qualitative abnormalities in reciprocal social interaction, and overactivity/agitation.