Association and linkage of alpha-2A adrenergic receptor gene polymorphisms with childhood ADHD. Transmission disequilibrium of polymorphic variants in the tryptophan hydroxylase-2 gene in attention-deficit/hyperactivity disorder A Pilot Twin Study of Psychological Measures of Attention Deficit Hyperactivity Disorder Dissecting the attention deficit hyperactivity disorder (ADHD) phenotype: Sustained attention, response variability and spatial attentional asymmetries in relation to dopamine transporter (DAT1) genotype Absence of the 7‐repeat variant of the DRD4 VNTR is associated with drifting sustained attention in children with ADHD but not in controls The homozygosity for 10-repeat allele at dopamine transporter gene and dopamine transporter density in Korean children with attention deficit hyperactivity disorder: relating to treatment response to methylphenidate Clinical symptoms and performance on the continuous performance test in children with attention deficit hyperactivity disorder between subtypes: a natural follow-up study for 6 months Adult outcome of attention-deficit/hyperactivity disorder: a controlled 16-year follow-up study. PREVALENCE ESTIMATIONS OF ATTENTION-DEFICIT/HYPERACTIVITY DISORDER: DIFFERENTIAL DIAGNOSES AND COMORBIDITIES IN A COLOMBIAN SAMPLE Attention-Deficit Hyperactivity Disorder (ADHD) symptoms and smoking patterns among participants in a smoking-cessation program. Moderators and mediators of treatment response for children with attention-deficit/hyperactivity disorder: the Multimodal Treatment Study of children with Attention-deficit/hyperactivity disorder. Characteristics of patients with schizophrenia successive to childhood attention deficit hyperactivity disorder (ADHD). Preschool children with disruptive behavior: three-year outcome as a function of adaptive disability. Disclosing the Disclosure: Factors Associated With Communicating the Results of Genetic Susceptibility Testing for Alzheimer's Disease Functional effects of the DAT1 polymorphism on EEG measures in ADHD. Using a Virtual Classroom environment to describe the attention deficits profile of children with Neurofibromatosis type 1. Predictors and consequences of adherence to the treatment of pediatric patients with attention-deficit/hyperactivity disorder in Central Europe and East Asia
Attention-deficit hyperactivity disorder ( ADHD ) is a heritable disorder , prevalent from childhood through adulthood . Although the noradrenergic ( NA ) system is thought to mediate a portion of the pathophysiology of ADHD , genes in this pathway have not been investigated as frequently as those in the dopaminergic system . Previous association studies of one c and i date gene in the NA system , ADRA2A , showed inconsistent results with regard to an MspI polymorphism . In the current study , two nearby single-nucleotide polymorphisms , which define HhaI and DraI restriction fragment length polymorphisms , were also genotyped and were in significant linkage disequilibrium with the MspI RFLP . Transmission disequilibrium tests ( TDTs ) in a sample of 177 nuclear families showed significant association and linkage of the DraI polymorphism with the ADHD combined subtype ( P=0.03 ) , and the quantitative TDT showed association of this polymorphism with the inattentive ( P=0.003 ) and hyperactive-impulsive ( P=0.015 ) symptom dimensions . The haplotype that contained the less common allele of the DraI polymorphism likewise showed a strong relationship with the inattentive ( P=0.001 ) and hyperactive-impulsive ( P=0.004 ) symptom dimensions . This study supports the hypothesis that an allele of the ADRA2A gene is associated and linked with the ADHD combined subtype and suggests that the DraI polymorphism of ADRA2A is linked to a causative polymorphism Attention-deficit/hyperactivity disorder ( ADHD ) is the most common behavioral disorder in childhood with substantial heritability . Pharmacological and molecular genetic studies as well as characterization of animal models have implicated serotonergic dysfunction in the pathophysiology of ADHD . Here , we investigated the effect of polymorphic variants in the gene of the tryptophan hydroxylase-2 ( TPH2 ) , the rate-limiting enzyme of serotonin ( 5-HT ) synthesis in the brain , in children and adolescents with ADHD . We analyzed three single nucleotide polymorphisms ( SNPs ) in and downstream of the transcriptional control region of the TPH2 gene in 103 families with 225 affected children .  Allelic association in families with more than one affected child was assessed using the pedigree disequilibrium test . Preferential transmissions were detected for the two SNPs in TPH2 's regulatory region ( rs4570625 , P=0.049 ; rs11178997 , P=0.034 ) , but not for the third SNP in intron 2 ( rs4565946 , P=0.3517 ) . Haplotype analysis revealed a strong trend of association between the regulatory region SNPs ( rs4570625 , rs11178997 ) and ADHD ( P=0.064 ) . Our results link potentially functional TPH2 variations to the pathophysiology of ADHD , and further support the relevance of 5-HT in disorders related to altered motor activity and cognitive processes There has been much interest in the genetics of attention deficit hyperactivity disorder and molecular genetic studies are now underway . The success of genetic studies will depend on how well the phenotype is defined . Twin studies using parent and teacher rated question naires or interviews all appear to yield highly heritable measures . Nevertheless , there is evidence to suggest that parent measures are subject to rater bias . Consequently there has been much interest in obtaining more objective measures of related traits such as attention span and impulsiveness using , computerised neuropsychological tasks . However there have been few twin studies examining the genetic contribution to these neuropsychological measures . The present study aims to investigate whether performance on the  Matching Familiar Figures Test ( MFFT ) and Continuous Performance Task ( CPT )  is genetically influenced in childhood . 20 monozygotic ( MZ ) and 20 dizygotic ( DZ ) twin pairs were r and omly selected from the Greater Manchester Twin Register . Preliminary data suggest that MZ twins perform more similarly than DZ twins on the MFFT , but not the CPT . Future work needs to examine whether other neuropsychological measures commonly used in research on ADHD are genetically influenced using larger twin sample ADHD is a childhood-onset behavioural disorder with a heterogeneous profile of neuropsychological impairment . Neuropsychological heterogeneity may , in part , reflect underlying genetic differences . Here we examined sustained attention , response variability and spatial attentional asymmetries in a sample of children and adolescents with ADHD ( n=22 ) in relation to dopamine transporter genotype ( DAT1 ) and also controls ( n=20 ) . Participants performed the sustained attention to response task ( SART ) ( testing sustained attention and response variability ) and the greyscales task ( a perceptual measure of attentional bias ) . The latter has previously been shown to yield a robust leftward attentional asymmetry in healthy subjects . The 10-repeat allele of the DAT1 gene has been associated with ADHD in a number of studies and appears to have biological significance . The ADHD group was sub-divided into those individuals with two copies of the " high-risk " 10-repeat allele ( high-risk DAT1 ) versus those with one or no copies of this allele ( low-risk DAT1 ) . The high-risk DAT1 ADHD group displayed greater response variability on the SART than either the low-risk DAT1 group or healthy controls , whereas the latter two groups did not differ . Further , the high-risk DAT1 group showed an attenuated spatial asymmetry , relative to the low-risk DAT1 ADHD group , who showed the typical leftward attentional asymmetry . Our results suggest that the 10-repeat DAT1 allele may mediate neuropsychological impairment in ADHD . The application of molecular genetics may help to define neuropsychological impaired subgroups of ADHD Many genetic studies have demonstrated an association between the 7‐repeat ( 7r ) allele of a 48‐base pair variable number of t and em repeats ( VNTR ) in exon 3 of the DRD4 gene and the phenotype of attention deficit hyperactivity disorder ( ADHD ) . Previous studies have shown inconsistent associations between the 7r allele and neurocognitive performance in children with ADHD . We investigated the performance of 128 children with and without ADHD on the Fixed and R and om versions of the Sustained Attention to Response Task ( SART ) . We employed time‐series analyses of reaction‐time data to allow a fine‐grained analysis of reaction time variability , a c and i date endophenotype for ADHD . Children were grouped into either the 7r‐present group ( possessing at least one copy of the 7r allele ) or the 7r‐absent group . The ADHD group made significantly more commission errors and was significantly more variable in RT in terms of fast moment‐to‐moment variability than the control group , but no effect of genotype was found on these measures . Children with ADHD without the 7r allele made significantly more omission errors , were significantly more variable in the slow frequency domain and showed less sensitivity to the signal ( d ' ) than those children with ADHD the 7r and control children with or without the 7r . These results highlight the utility of time‐series analyses of reaction time data for delineating the neuropsychological deficits associated with ADHD and the DRD4 VNTR . Absence of the 7‐repeat allele in children with ADHD is associated with a neurocognitive profile of drifting sustained attention that gives rise to variable and inconsistent performance . © 2008 Wiley‐Liss , The symptoms of attention deficit hyperactivity disorder ( ADHD ) can be treated with methylpheni date ( MPH ) , a potent blocker of dopamine transporter ( DAT ) . The homozygosity of the 10-repeat allele at the DAT gene ( DAT1 ) seems to be associated with a poor response to MPH in children with ADHD . In the present study , we investigated the association between DAT density using I-123-N-(3-iodopropen-2-yl)-2beta-carbomethoxy-3beta-(4-chlorophenyl)tropane [123I]IPT single photon emission computed tomography ( SPECT ) ] and the homozygosity for 10-repeat allele at DAT1 and response to MPH in Korean children with ADHD . Eleven drug-naive children with ADHD were included in the study and treated with MPH for about 8 weeks . After the genotyping and SPECT were performed , we compared DAT density between ADHD children with and without the homozygosity for 10-repeat allele at DAT1 and investigated the correlation between the homozygosity for 10-repeat allele and response to MPH .  ADHD children with 10/10 genotype ( n=7 ) had a significantly greater increase of the DAT density in basal ganglia than the children without 10/10 genotype ( n=4 ) . We found that while only 28.6 % ( 2/7 ) of the subject with 10/10 genotype showed good response to  MPH  treatment , 100 % ( 4/4 ) of the subjects without 10/10 genotype showed good response to  MPH treatment . Our findings support an association between homozygosity for 10-repeat allele at DAT1 and the DAT density assessed in vivo and correlation between the homozygosity for 10-repeat allele and poor response to MPH Background The aims of this study were to determine the time course of improvements in attention deficit hyperactivity disorder ( ADHD ) clinical symptoms and neurocognitive function in a realistic clinical setting , and the differences in ADHD symptom improvement using different classifications of ADHD subtypes . Methods The Child Behavior Checklist ( CBCL ) was completed by parents of ADHD children at the initial visit . The  computerized Continuous Performance Test ( CPT ) , Swanson , Nolan , and Pelham , and Version IV Scale for ADHD ( SNAP-IV ) , and  ADHD Rating Scale ( ADHD-RS ) were performed at baseline , one month , three months , and six months later , respectively . Patient care including drug therapy was performed at the discretion of the psychiatrist . The ADHD patients were divided into DSM-IV subtypes ( Inattentive , Hyperactive-impulsive and Combined type ) , and were additionally categorized into aggressive and non-aggressive subtypes by aggression scale in CBCL for comparisons . Results There were 50 ADHD patients with a mean age of 7.84 ± 1.64 years ; 15 of them were inattentive type , 11 were hyperactive-impulsive type , and 24 were combined type . In addition , 28 of the ADHD patients were grouped into aggressive and 22 into non-aggressive subtypes . There were significant improvements in clinical symptoms of hyperactivity and inattention , and impulsivity performance in CPT during the 6-month treatment . The clinical hyperactive symptoms were significantly different between ADHD patients sub-grouping both by DSM-IV and aggression . Non-aggressive patients had significantly greater changes in distraction and impulsivity performances in CPT from baseline to month 6 than aggressive patients . Conclusions We found that ADHD symptoms , which included impulsive performances in CPT and clinical inattention and hyperactivity dimensions , had improved significantly over 6 months under pragmatic treatments . The non-aggressive ADHD patients might have a higher potential for improving in CPT performance than aggressive ones . However , it warrant further investigation whether the different classifications of ADHD patients could be valid for predicting the improvements in ADHD patients ' clinical symptoms and neurocognitive performance OBJECTIVE To estimate the risks for psychopathology and functional impairments in adulthood among a longitudinal sample of youth with and without attention-deficit/hyperactivity disorder ( ADHD ) diagnosed in childhood . METHOD This was a case-controlled , 16-year ( 15 - 19 years ) prospect i ve follow-up study of ADHD . 140 boys with and 120 without DSM-III-R ADHD were recruited from pediatric and psychiatric setting s. The main outcome measures were  structured diagnostic interviews and measures of psychosocial , educational , and neuropsychological functioning . Data were collected from 1988 to 2006 . RESULTS At the 16-year follow-up , subjects with ADHD continued to significantly differ from controls in lifetime rates of antisocial , mood , anxiety , and addictive disorders , but with the exception of a higher interval prevalence of anxiety disorders ( 20 % vs 8 % ; z = 2.32 , P = .02 ) and smoking dependence ( 27 % vs 11 % ; z = 2.30 , P = .02 ) , the incidence of individual disorders in the 6-year interval between the current and prior follow-up did not differ significantly from controls . At follow-up , the ADHD subjects compared with controls were significantly ( P < .05 ) more impaired in psychosocial , educational , and neuropsychological functioning , differences that could not be accounted for by other active psychopathology . CONCLUSIONS These long-term prospect i ve findings provide further evidence for the high morbidity associated with ADHD across the life cycle , stressing the importance of early recognition of this disorder for prevention and early intervention strategies . These findings also indicate that , in adulthood , ADHD confers significant risks for impairment that can not be accounted for by other psychopathology The aim of this article was to analyze the prevalence of Attention Deficit/ Hyperactivity Disorder ( ADHD ) in Colombian Paisa children and adolescents . A r and omized sample of 4- to 17-year-old children and adolescents--176 males and 154 females -- was selected from schools in Manizales , Colombia . The diagnosis of ADHD was obtained using a semistructured psychiatric and neurological interview , medical histories revision , and neurological or psychiatric evaluations .  Several rating scales and a neuropsychological assessment  were administered in order to confirm the diagnosis . Children with Full Scale Intelligence Quotient ( FSIQ ) between 71 and 84 were recorded as having Borderline Intellectual Functioning ( BIF ) , and those with a history of mild motor retardation , and /or Performance Intelligence Quotient ( PIQ ) lower than 71 , were recorded as having a Developmental Coordination disorder ( DCD ) , after confirmation by neurological and neuropsychological examinations . BIF and DCD children were excluded from the ADHD group . Total prevalence of ADHD adjusted by sex was 16.4 % ( males 19.8 % and females 12.3 % ) . Prevalence of clean ADHD cases was 11.5 % , distrib uted as follows : combined type , 6.4 % ; inattentive , 4.8 % ; and hyperactive-impulsive , 0.3 % . Distribution by sex was as follows : males , 14.8 % ; and females , 7.7 % ; with an odds ratio of 2.1 ( 95 % CI : 1 - 4.5 , h 2 = 4.0 , p < . 05 ) . Clean prevalence of ADHD adjusted by equal sex distribution was 11.3 % . Prevalence of BIF was 5.8 % , DCD 3.0 % , and mild mental retardation 3.9 % . Prevalence of ADHD did not show differences by socioeconomic status ( SES ) , in contrast to mild mental retardation in which BIF and DCD were significantly more frequent in the lower SES Previous research has suggested an increased liability to smoking among individuals with Attention-Deficit Hyperactivity Disorder ( ADHD ) . This link is thought to be attributable , in part , to nicotine 's beneficial effects on attention and performance . In the present study , we examined the association of ADHD symptoms of inattention and hyperactivity with smoking behavior in a sample of 226 male and female smokers ages 18 and older who were enrolled in a smoking-cessation program .  Prior to treatment , they completed measures of ADHD symptoms and st and ardized measures of smoking patterns . Hierarchical linear regression models were used to characterize the smoking patterns associated with ADHD inattention and hyperactivity symptoms , controlling for potential confounder variables . Smoking for stimulation purpose s and the urge to smoke to minimize withdrawal symptoms were the primary patterns associated with ADHD inattention symptoms , while hyperactivity symptoms were not associated with smoking patterns . Consistent with a self-medication hypothesis , these results suggest that smokers with frequent symptoms of inattention may use nicotine as a stimulant drug to help manage these symptoms . Future studies of the role of inattention symptoms in response to smoking treatment are warranted BACKGROUND Intent-to-treat analyses of the study revealed that medication management , alone or combined with intensive behavioral treatment , was superior to behavioral treatment and community care in reducing attention-deficit/hyperactivity disorder ( ADHD ) symptoms ; but only combined treatment showed consistently greater benefit than community care across other outcome domains ( disruptive and internalizing symptoms , achievement , parent-child relations , and social skills ) . We examine response patterns in subgroups defined by baseline variables ( moderators ) or variables related to treatment implementation ( mediators ) . METHODS We reconducted r and om-effects regression ( RR ) analyses , adding factors defined by moderators ( sex ,  prior medication use  ,  comorbid disruptive or anxiety disorder  , and public assistance ) and a mediator ( treatment acceptance/attendance ) . RESULTS Study outcomes ( N = 579 ) were upheld in most moderator subgroups ( boys and girls , children with and without prior medication , children with and without comorbid disruptive disorders ) . Comorbid anxiety disorder did moderate outcome ; in participants without anxiety , results paralleled intent-to-treat findings . For those with anxiety disorders , however , behavioral treatment yielded significantly better outcomes than community care ( and was no longer statistically different from medication management and combined treatment ) regarding ADHD-related and internalizing symptoms . In families receiving public assistance , medication management yielded decreased closeness in parent-child interactions , and combined treatment yielded relatively greater benefits for teacher-reported social skills . In families with high treatment acceptance/attendance , intent-to-treat results were upheld . Acceptance/attendance was particularly important for medication treatments . Finally , two thirds of children given community care received stimulants . Behavioral treatment did not significantly differ from , but medication management was superior to , this subgroup . CONCLUSIONS Exploratory analyses revealed that our study ( the Multimodal Treatment Study of Children With Attention-Deficit/Hyperactivity Disorder [ MTA ] ) results were confirmed across most baseline variables and treatment acceptance/attendance . In children with ADHD plus anxiety , behavioral treatment surpassed community care and approached medication-based treatments regarding parent-reported ADHD symptoms The goal of this study was to investigate the characteristics of schizophrenic patients with a history of childhood attention deficit hyperactivity disorder ( ADHD ) . The study was performed on 37 adolescent patients meeting the DSM-III-R criteria for schizophrenia and ADHD and 40 controls with schizophrenia only . Schizophrenic patients who were diagnosed in childhood as suffering from ADHD had more prominent developmental disturbances in infancy , more insidious course of schizophrenia , failed to respond to neuroleptics and had poorer outcome as compared to patients with schizophrenia only . The results of this study indicate that schizophrenia subsequent to childhood ADHD has a poor prognosis as compared to schizophrenia only A significant discrepancy between intelligence and daily adaptive functioning , or adaptive disability ( AD ) , has been previously found to be a associated with significant psychological morbidity in preschool children with disruptive behavior ( DB ) . The utility of AD as a predictor of later developmental risks was examined in a 3-year longitudinal study of normal ( N = 43 ) and DB preschool children . The DB children were grouped into those with AD ( DB+AD ; N = 28 ) and those without AD ( DB-only ; N = 98 ) . All children were followed with annual evaluations to the end of second grade . Both DB groups demonstrated substantial and pervasive psychological and educational morbidity at 3-year follow-up . In comparison to DB-only children , DB+AD children had more symptoms of attention-deficit hyperactivity disorder ( ADHD ) and conduct disorder ( CD ) , more severe and pervasive behavior problems at home , more parent-rated externalizing and internalizing , and lower academic competence and more behavioral problems at school . Parents of DB+AD children also reported greater parenting stress than did parents in the other groups . A significant contribution of AD to adverse outcomes in the DB group remained on some measures even after controlling for initial severity of DB . AD also contributed significantly to CD symptoms at follow-up after controlling for initial DB severity and initial CD symptoms . The results corroborate and extend earlier findings of the utility of AD as a risk indicator above severity of DB alone . They also imply that AD in the context of normal intellectual development may arise from both the deficient self-regulation associated with ADHD and from disrupted parenting . with exposure to kindergarten moderating these adverse effects This study explored the extent to which recipients of genetic susceptibility testing for Alzheimer 's disease ( AD )  communicated their results to others . It also examined demographic characteristics , along with beliefs about AD , associated with such communication . Participants ( N = 271 ) in a r and omized clinical trial involving genetic testing for Apolipoprotein E ( APOE ) gene variants among first-degree relatives of AD patients reported their communication behaviors 6 weeks after the results disclosure . Information on beliefs about AD and genetic testing was collected at baseline . Eighty-two percent of participants receiving APOE genotype information shared their results with someone . Specifically , 64 % shared with family members , 51 % with spouse or significant others , 35 % with friends , and 12 % with health care professionals . Greater AD treatment optimism was associated with communicating results to family ( OR = 1.43 ) , spouse ( OR = 1.62 ) , friends ( OR = 1.81 ) , and health care professionals ( OR = 2.20 ) . Lower perceived risk ( OR = 0.98 ) and higher perceived importance of genetics in the development of AD ( OR = 1.93 ) were associated with results communication in general . Lower perceived drawbacks of AD genetic testing  was associated with results communication to friends ( OR = 0.65 ) . Beliefs about AD risks and causes , genetic testing , and development of treatments partly may determine the interpersonal communication patterns of genetic susceptibility test results OBJECTIVE This paper examines whether dopamine transporter gene ( DAT1 ) allele status mediates medication-related change in cognitive and neurophysiological measures among children with attention-deficiency/hyperactivity disorder ( ADHD ) . METHOD A single 10-mg dose of methylpheni date was given in a double-blind , placebo-controlled fashion to children with ADHD who were seen for cognitive testing and EEG recording . Buccal sample s were obtained and genotyped for the DAT1 polymorphism . RESULTS DAT1 allele status was associated with performance on a sustained attention task and medication-related EEG changes . Compared with those with one or more copies of the DAT1 9-repeat allele ( 9R ) , children with two copies of the 10-repeat allele ( 10R ) exhibited poorer performance on the vigilance task . In addition , children with 10R exhibited medication-related EEG changes of increased central and parietal beta power , decreased right frontal theta power , and lower theta/beta ratios ; 9R carriers showed the opposite pattern . CONCLUSIONS The data suggest that the DAT1 polymorphism mediates medication-related changes in cortical activity among children with ADHD The objectives of this study were to describe the nature of the attention deficits in children with Neurofibromatosis type 1 ( NF1 ) in comparison with typically developing ( TD ) children , using the Virtual Classroom ( VC ) , and to assess the utility of this instrument for detecting attention deficits . Twenty-nine NF1 children and 25 age- and gender-matched controls , aged 8 - 16 , were assessed in a VC . Parents ' ratings on the  Conners ' Parent Rating Scales-Revised : Long ( CPRS-R : L ) question naire were used to screen for Attention Deficit-Hyperactivity Disorder ( ADHD ) . Significant differences were found between the NF1 and the control groups on the number of targets correctly identified ( omission errors ) and the number of commissions ( commission errors ) in the VC , with poorer performance by the NF1 children ( p < 0.005 ) . Significant correlations were obtained between the number of targets correctly identified , the number of commission errors , and the reaction time . Significant correlations were also found between the total correct hits and the cognitive problems/inattention scale , as well as two other indexes of the CPRS-R : L : the DSM-IV Symptoms Subscale and the ADHD Index . The VC results support the hypothesis that NF1 is marked by inattention and impulsivity and that participants with NF1 are more inattentive ( omission errors ) and impulsive ( commission errors ) than normal controls . The VC appears to be a sensitive and ecologically valid assessment tool for use in the diagnosis of attention deficits among children with NF1 Purpose To assess baseline predictors and consequences of medication non-adherence in the treatment of pediatric patients with attention-deficit/hyperactivity disorder ( ADHD ) from Central Europe and East Asia . Patients and methods Data for this post-hoc analysis were taken from a 1-year prospect i ve , observational study that included a total of 1,068 newly-diagnosed pediatric patients with ADHD symptoms from Central Europe and East Asia .  Medication adherence during the week prior to each visit was assessed by treating physicians using a 5-point Likert scale , and then dichotomized into either adherent or non-adherent . Clinical severity was measured by the Clinical Global Impressions-ADHD-Severity ( CGI-ADHD ) scale and the Child Symptom Inventory-4 ( CSI-4 ) Checklist . Health-Related Quality of Life ( HRQoL ) was measured using the Child Health and Illness Profile-Child Edition ( CHIP-CE ) . Regression analyses were used to assess baseline predictors of overall adherence during follow-up , and the impact of time-varying adherence on subsequent outcomes : response ( defined as a decrease of at least 1 point in CGI ) , changes in CGI-ADHD , CSI-4 , and the five dimensions of CHIP-CE . Results Of the 860 patients analyzed , 64.5 % ( 71.6 % in Central Europe and 55.5 % in East Asia ) were rated as adherent and 35.5 % as non-adherent during follow-up . Being from East Asia was found to be a strong predictor of non-adherence . In East Asia , a family history of ADHD and parental emotional distress were associated with non-adherence , while having no other children living at home was associated with non-adherence in Central Europe as well as in the overall sample . Non-adherence was associated with poorer response and less improvement on CGI-ADHD and CSI-4 , but not on CHIP-CE . Conclusion Non-adherence to medication is common in the treatment of ADHD , particularly in East Asia . Non-adherence was associated with poorer response and less improvement in clinical severity . A limitation of this study is that medication adherence was assessed by the treating clinician using a single item question
Association of high reaction time variability with the 7-repeat allele absence appears to be the most consistent result and seems to be specific to ADHD .
Speed of processing , set-shifting and cognitive impulsiveness were less frequently investigated but seem to be altered in the 7-repeat allele carriers .
High reaction time variability seems to be the most replicated cognitive marker associated with the 10-repeat homozygosity .
BACKGROUND We review ed systematic ally the results of genetic studies investigating associations between putative susceptibility genes for attention-deficit hyperactivity disorder ( ADHD ) and neuropsychological traits relevant for this disorder .