Search results for "attention deficit hyperactivity disorder"

Candidate genetic pathways for attention-deficit/hyperactivity disorder (ADHD) show association to hyperactive/impulsive symptoms in children with AD…

2013

Item does not contain fulltext OBJECTIVE: Because multiple genes with small effect sizes are assumed to play a role in attention-deficit/hyperactivity disorder (ADHD) etiology, considering multiple variants within the same analysis likely increases the total explained phenotypic variance, thereby boosting the power of genetic studies. This study investigated whether pathway-based analysis could bring scientists closer to unraveling the biology of ADHD. METHOD: The pathway was described as a predefined gene selection based on a well-established database or literature data. Common genetic variants in pathways involved in dopamine/norepinephrine and serotonin neurotransmission and genes involv…

Children with autism and attention deficit hyperactivity disorder. Relationships between symptoms and executive function, theory of mind, and behavio…

2018

Abstract Background The underlying mechanisms of comorbidity between autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD) are still unknown. Executive function (EF) deficits and theory of mind (ToM) have been the most investigated cognitive processes. Aims This study proposed to analyze EF, ToM and behavioral problems in children with ASD + ADHD, ADHD, ASD and typical development (TD). The relationship between ADHD and ASD symptoms with EF, ToM and behavioral problems in children with ASD + ADHD was also explored. Methods and procedures Participants were 124 children between 7 and 11 years old (22 ASD + ADHD, 35 ADHD, 30 ASD, and 37 TD), matched on age and IQ. …

Efficacy and safety of extended-release guanfacine hydrochloride in children and adolescents with attention-deficit/hyperactivity disorder: A randomi…

2014

AbstractGuanfacine extended-release (GXR), a selective α2A-adrenergic agonist, is a non-stimulant treatment for attention-deficit/hyperactivity disorder (ADHD). This study assessed the efficacy (symptoms and function) and safety of dose-optimized GXR compared with placebo in children and adolescents with ADHD. An atomoxetine (ATX) arm was included to provide reference data against placebo. Patients (6–17 years) were randomized at baseline to dose-optimized GXR (0.05–0.12mg/kg/day – 6–12 years: 1–4mg/day; 13–17 years: 1–7mg/day), ATX (10–100mg/day) or placebo for 4 or 7 weeks. The primary efficacy measure was change from baseline in ADHD Rating Scale version IV (ADHD-RS-IV). Key secondary me…

Prospective relationships of ADHD symptoms with developing substance use in a population-derived sample

2011

BackgroundClinically ascertained reports suggest that boys and girls with attention deficit hyperactivity disorder (ADHD) may differ from each other in their vulnerability to substance use problems.MethodA total of 1545 Finnish adolescents were assessed for DSM-IV-based ADHD symptoms by their parents and classroom teachers using standardized rating scales at age 11–12 years. At age 14, substance use disorders and psychiatric co-morbidity were assessed with the Semi-Structured Assessment for the Genetics of Alcoholism, providing DSM-III-R/DSM-IV diagnoses for Axis I disorders. At age 17.5, substance use was assessed by multi-item questionnaire.ResultsAlthough baseline ADHD symptoms were less…

Meta-analysis of genome-wide association studies of attention-deficit/hyperactivity disorder

2010

Contains fulltext : 87688.pdf (Publisher’s version ) (Closed access) OBJECTIVE: Although twin and family studies have shown attention-deficit/hyperactivity disorder (ADHD) to be highly heritable, genetic variants influencing the trait at a genome-wide significant level have yet to be identified. As prior genome-wide association studies (GWAS) have not yielded significant results, we conducted a meta-analysis of existing studies to boost statistical power. METHOD: We used data from four projects: a) the Children's Hospital of Philadelphia (CHOP); b) phase I of the International Multicenter ADHD Genetics project (IMAGE); c) phase II of IMAGE (IMAGE II); and d) the Pfizer-funded study from the…

Corpus Callosum Morphology in Attention Deficit-Hyperactivity Disorder: Morphometric Analysis of MRI

1991

Although behavioral evidence provides support for the notion that attention deficit-hyperactivity disorder (ADHD) is related to central nervous system dysfunction, there is little direct evidence to reveal which neurometabolic systems or brain structures are involved. Recent magnetic resonance imaging (MRI) studies suggest that, compared to nondisabled controls, ADHD children may have a smaller right frontal region. Morphometric analysis of MRI scans was used in this exploratory study to determine whether correlated regional variation might exist in the corpus callosum of children with ADHD. While all MRI scans were judged to be clinically normal, morphometric analysis revealed that, compa…

Comorbidity between obesity and attention deficit/hyperactivity disorder: Population study with 13–15-year-olds

2006

Objective: This study analyzes whether obese children have a higher risk of attention deficit/hyperactivity “characteristics” (AD/HD) than do children with other nutritional states. Method: This study included 35,403 participants from 486 community schools. They completed the AD/HD scale of the Strengths and Difficulties Questionnaire (SDQ) and were weighed and measured. 2879 of the participants were obese and 78 were morbidly obese (BMI >40). Results: A discrete, nonsignificant, increment was found in the AD/HD characteristics of male participants with morbid obesity, as compared with the other nutritional states. Among morbidly obese females, the prevalence of AD/HD characteristics was sl…

DSM-IV Combined Type ADHD Shows Familial Association With Sibling Trait Scores

2008

Contains fulltext : 69060.pdf (Publisher’s version ) (Closed access) Attention deficit hyperactivity disorder (ADHD) is a discrete clinical syndrome characterized by the triad of inattention, hyperactivity, and impulsivity in the context of marked impairments. Molecular genetic studies have been successful in identifying genetic variants associated with ADHD, particularly with DSM-IV inattentive and combined subtypes. Quantitative trait locus (QTL) approaches to linkage and association mapping have yet to be widely used in ADHD research, although twin studies investigating individual differences suggest that genetic liability for ADHD is continuously distributed throughout the population, u…

2014

Disorders such as borderline personality disorder (BPD) or attention-deficit/hyperactivity disorder (ADHD) are characterized by impulsive behaviors. Impulsivity as used in clinical terms is very broadly defined and entails different categories including personality traits as well as different cognitive functions such as emotion regulation or interference resolution and impulse control. Impulse control as an executive function, however, is neither cognitively nor neurobehaviorally a unitary function. Recent findings from behavioral and cognitive neuroscience studies suggest related but dissociable components of impulse control along functional domains like selective attention, response selec…

Genetic relationship between five psychiatric disorders estimated from genome-wide SNPs

2013

AM Vicente - Cross-Disorder Group of the Psychiatric Genomics Consortium Most psychiatric disorders are moderately to highly heritable. The degree to which genetic variation is unique to individual disorders or shared across disorders is unclear. To examine shared genetic etiology, we use genome-wide genotype data from the Psychiatric Genomics Consortium (PGC) for cases and controls in schizophrenia, bipolar disorder, major depressive disorder, autism spectrum disorders (ASD) and attention-deficit/hyperactivity disorder (ADHD). We apply univariate and bivariate methods for the estimation of genetic variation within and covariation between disorders. SNPs explained 17-29% of the variance in …