Serotonin 2A Receptor Gene Polymorphism in Korean Children with Attention-Deficit/Hyperactivity Disorder

Objective

The purpose of this study was to investigate the association between the T102C polymorphism in the serotonin 2A receptor gene and attention-deficit/hyperactivity disorder (ADHD) in Korean patients.

Methods

A total of 189 Korean children with ADHD as well as both parents of the ADHD children and 150 normal children participated in this study. DNA was extracted from blood samples from all of the subjects, and genotyping was conducted. Based on the allele and genotype information obtained, case-control analyses were performed to compare the ADHD and normal children, and Transmission disequilibrium tests (TDTs) were used for family-based association testing (number of trios=113). Finally, according to the significant finding which was showed in the case-control analyses, the results of behavioral characterastics and neuropsychological test were compared between ADHD children with and without the C allele.

Results

In the case-control analyses, statistically significant differences were detected in the frequencies of genotypes containing the C allele (χ²=4.73, p=0.030). In the family-based association study, TDTs failed to detect linkage disequilibrium of the T102C polymorphism associated with ADHD children. In the ADHD children, both the mean reaction time and the standard deviation of the reaction time in the auditory continuous performance test were longer in the group with the C allele compared to the group without the C allele.

Conclusion

The results of this study suggest that there is a significant genetic association between the T102C polymorphism in the serotonin 2A receptor gene and ADHD in Korean children.     

COMT,neuropsychological function and brain structure in schizophrenia: a systematic review and neurobiological interpretation

Background

Endophenotypes in genetic psychiatry may increase our understanding of the molecular mechanisms underlying disease risk and its manifestations. We sought to investigate the link between neuropsychological impairments and brain structural abnormalities associated with the COMT Val¹⁵⁸Met polymorphism in patients with schizophrenia to improve understanding of the pathophysiology of this disorder.

Methods

We performed a systematic review using studies identified in PubMed and MEDLINE (from the date of the first available article to July 2012). Our review examined evidence of an association between the COMT Val¹⁵⁸Met polymorphism and both neuropsychological performance and brain structure in patients with psychosis, in their relatives and in healthy individuals (step 1). The review also explored whether the neuropsychological tasks and brain structures identified in step 1 met the criteria for an endophenotype (step 2). Then we evaluated evidence that the neuropsychological endophenotypes identified in step 2 are associated with the brain structure endophenotypes identified in that step (step 3). Finally, we propose a neurobiological interpretation for this evidence.

Results

A poorer performance on the n-back task and the Continuous Performance Test (CPT) and smaller temporal and frontal brain areas were associated with the COMT Val allele in patients with schizophrenia and their relatives and met most of the criteria for an endophenotype. It is possible that the COMT Val¹⁵⁸Met polymorphism therefore contributes to the development of these neuropsychological and brain structural endophenotypes of schizophrenia, in which the prefrontal cortex may represent the neural substrate underlying both n-back and CPT performances.

Limitations

The association between a single genetic variant and an endophenotype does not necessarily imply a causal relationship between them.

Conclusion

This evidence and the proposed interpretation contribute to explain, at least in part, the biological substrate of 4 important endophenotypes that characterize schizophrenia.     

Gender-specific association of the brain-derived neurotrophic factor gene with attention-deficit/hyperactivity disorder

Objective

Attention-deficit/hyperactivity disorder (ADHD) is a complex neurodevelopmental disorder with a strong genetic component. Brain-derived neurotrophic factor (BDNF), which participates in the differentiation and survival of dopaminergic and noradrenergic neurons, could play a role in ADHD development. We aimed to explore the relationships between ADHD and BDNF gene polymorphism.

Methods

We conducted a case-control analysis of 202 ADHD subjects and 159 controls, performed a transmission disequilibrium test on 151 trios, and compared the results of a continuous performance test (CPT) according to the genotype of the three single nucleotide polymorphisms (rs11030101, rs6265, rs16917204) in the BDNF gene.

Results

In the case-control analysis, the AA genotype of the BDNF rs11030101 polymorphism was significantly associated with ADHD only in girls (p=0.024, odds ratio=3.00). The T-G-G haplotype was significantly less frequent (p=0.005) and A-G-G was more frequent (p=0.048) in girls with ADHD than in control girls (global p=0.027). A multivariate analysis of variance for commission errors on the CPT showed a significant main effect for the rs11030101 genotype (p=0.026) and an interaction effect of the rs11030101 genotype and gender (p=0.032) in ADHD probands.

Conclusion

These results provide preliminary evidence for a gender-specific association between BDNF and ADHD in the Korean population.     

Catechol-O-methyltransferase genotype modifies executive functioning and prefrontal functional connectivity in women with anorexia nervosa

Background

Anorexia nervosa is characterized by high levels of perseveration and inflexibility, which interfere with successful treatments. Dopamine (DA) signalling seems to play a key role in modulating the prefrontal cortex, since both DA deficiency and excess negatively influence the efficiency of cognitive functions. The present study explores the effect of a functional polymorphism (Val158Met) in the catechol-O-methyltransferase (COMT) gene on the set-shifting abilities and prefrontal functional connectivity of patients with anorexia nervosa.

Methods

All participants performed the Wisconsin Card Sorting Task, and a subsample underwent resting-state functional magnetic resonance imaging.

Results

We included 166 patients with DSM-IV lifetime anorexia nervosa and 140 healthy women in our study. Both underweight and weight-recovered patients with anorexia nervosa showed high levels of perseveration, but only in the underweight group did the Val158Met polymorphism affect cognitive performance, showing the U-shaped curve characteristic of increased DA signalling in the prefrontal cortex. Underweight patients with anorexia nervosa who are Met homozygotes had significantly higher levels of perseveration and increased prefrontal functional connectivity than underweight patients in the other genotype groups, indicating abnormal regional cortical processing.

Limitations

Although our data show that grey matter reduction in starving patients with anorexia nervosa did not explain our findings, the cross-sectional design of the present study did not allow us to distinguish between the effects of starvation and those of low estrogen levels.

Conclusion

Starvation affects DA release in the prefrontal cortex of patients with anorexia nervosa with different effects on executive functioning and prefrontal functional connectivity according to the COMT genotype. This observation has several therapeutic implications that need to be addressed by future studies.     

Association between Antipsychotics-Induced Restless Legs Syndrome and Tyrosine Hydroxylase Gene Polymorphism

Objective

Restless legs syndrome (RLS) has been reported to be more prevalent in schizophrenic patients who take antipsychotics. The cause of RLS is unknown but associated with dopaminergic deficiency. Tyrosine hydroxylase (TH) is the enzyme responsible for catalyzing the conversion of L-tyrosine to DOPA. The purpose of this study is to determine whether the TH gene Val81Met polymorphism is associated with antipsychotic-induced RLS.

Methods

One hundred ninety Korean schizophrenic patients were evaluated by the diagnostic criteria of the International RLS Study Group (IRLSSG). The genotyping was performed by PCR-based methods.

Results

Of the one hundred ninety schizophrenic patients, 44 (23.2%) were found to have RLS. Although there were no significant associations between TH genotypes or allele frequencies and RLS, when separate analyses were performed by sex (male or female), we detected significant differences in the frequencies of the genotype (χ²=6.15, p=0.046) and allele (χ²=4.67, p=0.031) of the TH gene Val81Met polymorphism between those with and without RLS in the female patients.

Conclusion

These findings suggest that the TH gene Val81Met SNP might be associated with antipsychotic-induced RLS in female schizophrenic patients.     

Catechol-O-methyltransferase val158met genotype determines effect of reboxetine on emotional memory in healthy male volunteers

Background

Catechol-O-methyltransferase (COMT) metabolizes catecholamines in the prefrontal cortex (PFC). A common polymorphism in the COMT gene (COMT val158met) has pleiotropic effects on cognitive and emotional processing. The met allele has been associated with enhanced cognitive processing but impaired emotional processing relative to the val allele.

Methods

We genotyped healthy, white men in relation to the COMT val158met polymorphism. They were given a single 4 mg dose of the selective noradrenaline reuptake inhibitor (NRI) reboxetine or placebo in a randomized, double-blind between-subjects model and then completed an emotional memory task 2 hours later.

Results

We included 75 men in the study; 41 received reboxetine and 34 received placebo. In the placebo group, met/met carriers did not demonstrate the usual memory advantage for emotional stimuli that was observed in val carriers. Reboxetine restored this emotional enhancement of memory in met/met carriers, but had no significant effect in val carriers.

Limitations

We studied only men, thus limiting the generalizability of our findings. We also relied on self-reported responses to screening questions to establish healthy volunteer status, and in spite of the double-blind design, participants were significantly better than chance at identifying their intervention allocation.

Conclusion

Emotional memory is impaired in healthy met homozygotes and selectively improved in this group by reboxetine. This has potential translational implications for the use of reboxetine, which is currently licensed as an antidepressant in several countries, and edivoxetine, a new selective NRI currently in development.     

Regional differences in cerebral perfusion associated with the α-2A-adrenergic receptor genotypes in attention deficit hyperactivity disorder

Background

Neurobiologic studies have suggested that dysregulation of central noradrenergic systems may be involved in the pathophysiology of attention deficit hyperactivity disorder (ADHD), and it has been hypothesized that genetic changes in the norepinephrine pathways might contribute to dysfunction of the prefrontal cortex circuits in ADHD. We previously reported decreased cerebral blood flow in the right lateral prefrontal cortex and both orbitofrontal cortices in children with ADHD. Genetic investigations have shown that the α-2A-adrenergic receptor gene (ADRA2A) is associated with ADHD. Our aim was to examine whether the presence of a risk allele of the ADRA2A MspI polymorphism is associated with differences in regional cerebral blood flow in boys with ADHD.

Methods

We recruited 21 Korean boys with ADHD (mean age 9.9, standard deviation [SD] 2.7 yr) and 11 age- and sex-matched controls (mean age 10.6 [SD 2.1] yr). Each participant underwent technetium-99m-hexamethylpropylene amine oxime (^99mTc-HMPAO) single-photon emission computed tomography. We performed image analyses with voxel-wise t statistics using SPM2.

Results

We found regional hypoperfusion in the prefrontal regions, including the right orbitofrontal and right medial gyri, and the bilateral putamen and cerebellum in boys with ADHD relative to controls (p < 0.0005, uncorrected for multiple comparisons). Boys with ADHD who carried the C allele (n = 13) at the ADRA2A MspI polymorphism had reduced perfusion in the bilateral orbitofrontal regions compared with those without the C allele (n = 8) (p < 0.0005, uncorrected for multiple comparisons).

Limitations

This study was limited by the small sample size, and we did not obtain genetic data from the controls.

Conclusion

Our findings suggest that regional differences in cerebral perfusion in the orbitofrontal cortex represent an intermediate neuroimaging phenotype associated with the ADRA2A MspI polymorphism; these data support the validity of the noradrenergic hypothesis regarding the pathophysiology of ADHD.     

Genetic Contribution of Catechol-O-methyltransferase Polymorphism in Patients with Migraine without Aura

Background

Recent genetic association studies have investigated the possible genetic role of the dopaminergic system in migraine. Catechol-O-methyltransferase (COMT) is an enzyme that plays a crucial role in the metabolism of dopamine and its genetic polymorphism is associated with three- to fourfold variation of enzymatic activity.

Objectives

The objective of this study was to elucidate the role of the COMT polymorphism in the genetic susceptibility to migraine and its phenotypic expression in patients with migraine without aura (MWOA).

Methods

Ninety-seven patients with MWOA and 94 healthy volunteers were included in the study. After amplifying COMT genes by the polymerase chain reaction, we assessed their genotype frequencies and allele distributions by based on restriction fragment length polymorphisms. We classified all MWOA patients into two groups according to their COMT genotype: with the L allele (N = 43), and without this allele (N = 54).

Results

The genotype frequency and allele distribution of the COMT polymorphism did not differ between MWOA patients and the control group. During migraine attacks, MWOA patients with the L allele showed a higher pain intensity of headache (P = 0.001) and a higher incidence of the accompanying nausea/vomiting (94% vs 75%; P = 0.026) compared with MWOA patients without the L allele.

Conclusions

Although the COMT polymorphism does not appear to be involved in predisposition to the development of MWOA, this genetic factor could be involved in the phenotypic expression of MWOA.     

Association between Novelty Seeking of opiate-dependent patients and the catechol-O-methyltransferase ValMet polymorphism

Background

Candidate genes of the dopaminergic system have been reported as key elements in shaping human temperament. Catechol-O-methyltransferase (COMT) plays a vital role in dopamine inactivation, and the Val¹⁵⁸Met single nucleotide polymorphism (rs4680) in its gene has been recently associated with the Novelty Seeking (NS) temperament scale of the Temperament and Character Inventory in studies of healthy adults, as well as methamphetamine abusers.

Method

Our goal was to examine the association between temperament dimensions of the Temperament and Character Inventory and the COMT Val¹⁵⁸Met variation in a Hungarian sample of 117 heroin-dependent patients and 124 nondependent controls.

Results

Case-control analysis did not show any significant difference in allele or genotype distributions. However, dimensional approach revealed an association between the COMT Val¹⁵⁸Met and NS (P = .01): both controls and opiate users with Met/Met genotypes showed higher NS scores compared to those with the Val allele. The NS scores are also significantly higher among opiate users; however, no interaction was found between group status and COMT genotype.

Conclusion

Association of the COMT polymorphism and NS temperament scale has been shown for heroin-dependent patients and controls regardless of group status.     

No Evidence for Association between Tyrosine Hydroxylase Gene Val81Met Polymorphism and Susceptibility to Tardive Dyskinesia in Schizophrenia

Objective

Tyrosine hydroxylase (TH) is the rate-limiting enzyme in dopamine biosynthesis. Because the TH Val81Met polymorphism is located in the amino-terminal regulatory domain of the tetrameric enzyme, it is a candidate marker for susceptibility to dopamine-related traits. We investigated the hypothesis that TH Val81Met polymorphism can influence susceptibility to tardive dyskinesia (TD) in schizophrenia.

Methods

TH Val81Met polymorphism was analyzed by PCR-based methods in 83 schizophrenic patients with TD and 126 schizophrenic patients without TD, matched for antipsychotic drug exposure and other relevant variables.

Results

There was no significant association of the genotype and allele frequencies determined by the TH Val81Met polymorphism between TD and non-TD patients. In addition, there was no significant difference in terms of total Abnormal Involuntary Movement Scale scores among the three genotype groups.

Conclusion

Within the limitations imposed by the size of the clinical sample, these findings suggest that the Val81Met polymorphism of the TH gene does not contribute significantly to the risk for TD.     

The WHO Adult ADHD Self-Report Scale: Reliability and Validity of the Korean Version

Objective

A self-report scale of adult attention-deficit/hyperactivity disorder, the World Health Organization (WHO) Adult ADHD Self-Report Scale (ASRS) was developed and demonstrated good psychometric properties. The purpose of the present study is to investigate the psychometric properties of the ASRS in Korean samples.

Methods

The ASRS includes 18 questions regarding the frequency of recent DSM-IV Criterion A symptoms of adult ADHD. We examined the factor structure, internal consistency, and convergent validity of the ASRS in Korean samples.

Results

The ASRS demonstrated good internal consistency and test-retest reliability. Correlations between the ASRS and other adult ADHD measures were high, providing evidence of convergent validity. A subsequent exploratory factor analysis indicated that a two-factor solution provided the best fit.

Conclusion

It is expected that this scale would be helpful in clinical settings and research in Korea.     

Association of VAMP-2 and Syntaxin 1A Genes with Adult Attention Deficit Hyperactivity Disorder

Objective

The etiology of attention deficit hyperactivity disorder (ADHD) has not been entirely clarified yet. Structural and metabolic differences at the prefrontal striatal cerebellary system and the interaction of gene and environment are the main factors that thought to play roles in the etiology. Genetic investigations are performed especially about the dopamine pathways and receptors. In this study; it was aimed to investigate the association of the synaptobrevin-2 (VAMP-2) gene Ins/Del polymorphism and syntaxin 1A gene intron 7 polymorphism, which take place in encoding presynaptic protein, with adult ADHD.

Methods

One hundred thirty-nine patients, having ADHD aging between 18 and 60 years and 106 healthy people as controls were included into the study. DNA samples were extracted from whole blood and genetic analysis were performed.

Results

A significant difference was determined between ADHD and VAMP-2 Ins/Del polymorphism and syntaxin 1A intron 7 polymorphism according to the control group. These polymorphisms were found not to be associated with subtypes of ADHD.

Conclusion

It is supposed that synaptic protein genes together with dopaminergic genes might have roles in the etiology of ADHD.     

Association between RELN Gene Polymorphisms and Attention Deficit Hyperactivity Disorder in Korean Children

Objective

Attention deficit hyperactivity disorder (ADHD) is common disorder of the school-age population. ADHD is familial and genetic studies estimate heritability at 80–90%. The aim of the present study was to investigate the association between the genetic type and alleles for RELNgene (rs736707, rs2229864, rs362746, rs362726, rs362691, rs1062831, rs607755, and rs2072403) in Korean children with ADHD.

Methods

The sample consisted of 180 ADHD children and 159 control children. We diagnosed ADHD according to DSM-IV. ADHD symptoms were evaluated with Conners'' Parent Rating Scales and Dupaul Parent ADHD Rating Scales. Blood samples were taken from the 339 subjects, DNA was extracted from blood lymphocytes, and PCR was performed for RELN Polymorphism. Alleles and genotype frequencies were compared using the chi-square test. We compared the allele and genotype frequencies of RELN gene polymorphism in the ADHD and control groups.

Results

This study showed that there was a significant correlation among the frequencies of the rs736707 (OR=1.40, 95% CI=1.03–1.90, p=0.031) of alleles of RELN, but the final conclusions are not definite.

Conclusion

Follow up studies with larger patient or pure subgroups are expected. These results suggested that RELN might be related to ADHD symptoms.     

A comparison of comorbidity and psychological outcomes in children and adolescents with attention-deficit/hyperactivity disorder

Objective

The purpose of this study was to compare psychiatric comorbid disorders and psychological outcomes in children and adolescents with Attention-deficit/hyperactivity disorder (ADHD).

Methods

Subjects were divided into a child group (aged under 12 years) and an adolescent group (aged 12 years and above). All subjects were diagnosed with ADHD based on the DSM IV diagnostic criteria using the Kiddie-Schedule for Affective Disorders and Schizophrenia-Present and Lifetime Korean Version (K-SADS-PL-K). The K-SADS-PL-K was also used to evaluate those psychiatric disorders comorbid with ADHD. And the Korean version of the Child Behavior Checklist (K-CBCL) was used to examine the subjects'' psychological outcomes.

Results

The rate of comorbidity in adolescent group was significantly higher than that in the child group. In particular, the adolescent group had a significantly higher ratio of comorbid conduct disorder and mood disorder than the child group. With respect to the predominantly inattentive type and Not Otherwise Specified, the school subscale scores on the K-CBCL for the children were significantly higher than those for the adolescents.

Conclusion

These results suggest that the psychiatric comorbidity may differ between adolescents and children with ADHD. Therefore when treating adolescents with ADHD, more careful assessment and treatment targeting a range of comorbidities are needed.     

Association of SNAP-25 Gene Ddel and Mnll Polymorphisms with Adult Attention Deficit Hyperactivity Disorder

Objective

The synaptosomal-associated protein of 25 kDa (SNAP-25) gene is a presynaptic plasma membrane protein and an integral component of the vesicle docking and fusion machinery mediating secretion of neurotransmitters. Previously, several studies reported association between SNAP-25 and attention deficit hyperactivity disorder (ADHD). We investigated whether these SNAP-25 polymorphisms (MnlI T/G and DdelI T/C) were also associated with ADHD in the Turkish population.

Methods

Our study comprised unrelated 139 subjects who met DSM-IV criteria for ADHD and 73 controls and all were of Turkish origin. Genetic analyses were performed and patients were evaluated with Wender-Utah Rating Scale and Adult ADD/ADHD DSM IV-Based Diagnostic Screening and Rating Scale.

Results

SNAP-25 DdelI polymorphism was not associated with ADHD but there was a statistically significant difference between ADHD patients and controls for SNAP-25 MnlI polymorphism. For SNAP-25 MnlI polymorphism patients with G/G genotype of the SNAP-25 gene MnlI polymorphism had higher Wender-Utah scores and higher scores in the 1st and 3rd parts of adult ADD/ADHD Scale.

Conclusion

We detected a significant association of the MnlI polymorphism in our ADHD sample which was similar to previous findings. Our study also revealed that SNAP-25 MnlI polymorphism was also associated with symptom severity of ADHD. This study is also, the first report on the association of SNAP-25 with ADHD in the Turkish population.     

Perinatal and Familial Risk Factors Are Associated with Full Syndrome and Subthreshold Attention-Deficit Hyperactivity Disorder in a Korean Community Sample

Objective

The objective of this study was to examine the effect of perinatal and familial risk factors on full syndrome and subthreshold attention-deficit/hyperactivity disorder (ADHD) among Korean children and adolescents.

Methods

A sample of 2,673 students was randomly selected from 19 representative schools in Seoul, Korea. The parents of the students completed the Diagnostic Interview Schedule for Children-version IV (DISC-IV), as well as questionnaires on perinatal and familial risk factors.

Results

Maternal stress and alcohol use during pregnancy, parental marital discord, parental separation or divorce, changes in primary caregivers, and notbreastfeeding were significantly associated with full syndrome ADHD; however, maternal stress during pregnancy was the only variable that differentiated subthreshold ADHD from non-ADHD.

Conclusion

Our results provide evidence the perinatal and familial risk factors contribute to the development of ADHD in Korea children and adolescents, and suggest that these perinatal and familial risk factors are more closely related to full syndrome than to subthreshold ADHD.     

Mediating Effect of Depressive Symptoms on the Relationship between Adult Attention Deficit Hyperactivity Disorder and Quality of Life

Objective

The aim of this study was to investigate whether depressive symptoms affect the relationship between adult attention deficit hyperactivity disorder (ADHD) and the quality of life (QOL) in Korean soldiers.

Methods

We evaluated past and present symptoms of adult ADHD (the Korean Adult Attention-Deficit/Hyperactivity Disorder Scale and the Wender Utah Rating Scale), depression (the Center for Epidemiological Studies Depression Scale) and QOL (the Korean version of the SmithKline Beecham ''Quality of Life'' scale) in 131 soldiers during mental health screenings performed by a local mental health center. A structured equation model using AMOS 19.0 was used to evaluate the mediating effect of depression.

Results

In our first model (without depressive symptoms), adult ADHD significantly affected QOL (standardized regression weight=-0.51, p<0.01). After depressive symptoms were added to this model, the direct effect of adult ADHD on QOL was not significant (standardized regression weight=0.10, p=0.43). Regarding the indirect effect, adult ADHD significantly affected depression (standardized regression weight=0.78, p<0.01), and depression also affected QOL (standardized regression weight=-0.79, p<0.01).

Conclusion

Through structural equation modeling, the complete mediation model for the influence of depressive symptoms on ADHD and QOL was confirmed. These findings indicated that it might be important to consider comorbidities, such as depression, when adult ADHD is being evaluated.     

Association of Hair Manganese Level with Symptoms in Attention-Deficit/Hyperactivity Disorder

Objective

The study examined the association between hair manganese level and symptoms of attention-deficit/hyperactivity disorder (ADHD) in Korean children.

Methods

Forty clinic-referred children with ADHD and 43 normal control children participated in this study. The participants were 6-15 years old and were mainly from the urban area of Seoul, Korea. ADHD was diagnosed using the Diagnostic and Statistical Manual of Mental Disorders, 4th edition and Kiddie-Schedule for Affective Disorders and Schizophrenia-Present and Lifetime Version-Korean Version. The severity and symptoms of ADHD was evaluated according to the ADHD Diagnostic System, and parent''s Korean ADHD Rating Scale (K-ARS). All participants completed intelligence test and hair mineral analysis. We divided the data of hair Mn into two groups to determine whether a deficit or excess of Mn are associated with ADHD. Multiple logistic regression analyses were performed to identify hair manganese levels associated with ADHD, controlling for age, sex, and full scale intelligence quotient (IQ).

Results

The proportion of abnormal range Mn group was significantly high in ADHD compared to controls. However, after statistical control for covariates including age and sex, abnormal range Mn group was significantly associated with ADHD (OR=6.40, 95% CI=1.39-29.41, p=0.017).

Conclusion

The result of this study suggests that excess exposure or deficiency of Mn were associated with ADHD among children in Korea. Further investigation is needed to evaluate the effects of hair manganese levels on symptoms in ADHD.     

Cognitive Function in Childhood Epilepsy: Importance of Attention Deficit Hyperactivity Disorder

Background and Purpose

To determine how cognitive function is related to epilepsy classification and comorbid attention deficit hyperactivity disorder (ADHD) in children with newly diagnosed epilepsy of genetic or unknown etiology.

Methods

The medical records of children aged 6-16 years with newly diagnosed epilepsy of genetic or unknown etiology were reviewed retrospectively. The Korean Education Development Institute-Wechsler Intelligence Scale for Children and the Comprehensive Attention Test were used to evaluate intelligence and attention/executive function, respectively.

Results

The data of a total of 149 children, 103 with focal seizures and 46 with generalized seizures, were reviewed. The prevalence of ADHD was 49.2% (59 out of 120 examined patients), and ADHD patients exhibited significantly worse auditory selective attention, flanker test results, and spatial working memory. Patients with generalized seizures exhibited significantly worse auditory selective and sustained attention than patients with focal seizures. In patients with generalized seizures, sustained attention, flanker test findings, and spatial working memory were found to be affected by ADHD, and auditory selective and sustained attention were significantly worse in patients with benign childhood epilepsy with centrotemporal spikes and ADHD than in their counterparts without ADHD.

Conclusions

Cognitive processes are affected by seizure type and comorbid ADHD. Proper characterization of these neuropsychiatric impairments may allow earlier intervention during the disease course.