ADHD-C Group Research Articles

Neuropsychological Profile Related with Executive Function of Chinese Preschoolers with Attention-Deficit/Hyperactivity Disorder: Neuropsychological Measures and Behavior Rating Scale of Executive Function-Preschool Version.

Background:Previous studies have found that schoolchildren with attention-deficit/hyperactivity disorder (ADHD) showed difficulties in neuropsychological function. This study aimed to assess neuropsychological function in Chinese preschoolers with ADHD using broad neuropsychological measures and rating scales and to test whether the pattern and severity of neuropsychological weakness differed among ADHD presentations in preschool children.Methods:The 226 preschoolers (163 with ADHD and 63 controls) with the age of 4–5 years were included and assessed using the Behavior Rating Scale of Executive Function-Preschool Version (BRIEF-P) and a series of tests to investigate neuropsychological function.Results:Preschoolers with ADHD showed higher scores in all domains of the BRIEF-P (inhibition: 30.64 ± 5.78 vs.20.69 ± 3.86, P < 0.001; shift: 13.40 ± 3.03 vs.12.41 ± 2.79, P = 0.039; emotional control:15.10 ± 3.53 vs.12.20 ± 2.46, P < 0.001; working memory: 28.41 ± 4.99 vs.20.95 ± 4.60, P < 0.001; plan/organize: 17.04 ± 3.30 vs.13.29 ± 2.40, P < 0.001) and lower scores of Statue (23.18 ± 7.84 vs.28.27 ± 3.18, P = 0.001), Word Generation (15.22 ± 6.52 vs.19.53 ± 7.69, P = 0.025), Comprehension of Instructions (14.00 ± 4.44 vs.17.02 ± 3.39, P = 0.016), Visuomotor Precision (P < 0.050), Toy delay (P = 0.048), and Matrices tasks (P = 0.011), compared with normal control. In terms of the differences among ADHD subtypes, all ADHD presentations had higher scores in several domains of the BRIEF-P (P < 0.001), and the ADHD-combined symptoms (ADHD-C) group had the poorest ratings on inhibition and the ability to Plan/Organize. For neuropsychological measures, the results suggested that the ADHD-C group had poorer performances than the ADHD-predominantly inattentive symptoms (ADHD-I) group on Statue tasks (F = 7.34, η2 = 0.12, P < 0.001). Furthermore, the ADHD-hyperactive/impulsive symptoms group had significantly poorer performances compared to the ADHD-C group in the Block Construction task (F = 4.89, η2 = 0.067, P = 0.003). However, no significant group differences were found between the ADHD-I group and normal control.Conclusion:Based on the combined evaluation of performance-based neuropsychological tests and the BRIEF-P, preschoolers with ADHD show difficulties of neuropsychological function in many aspects.

Investigation of attention deficit hyperactivity disorder (ADHD) sub-types in children via EEG frequency domain analysis

ABSTRACTAim of the study: To investigate the frequency domain effects and changes in electroencephalography (EEG) signals in children diagnosed with attention deficit hyperactivity disorder (ADHD).Patients and methods: The study contains 40 children. All children were between the ages of 7 and 12 years. Participants were classified into four groups which were ADHD (n=20), ADHD-I (ADHD-Inattentive type) (n=10), ADHD-C (ADHD-Combined type) (n=10), and control (n=20) groups. In this study, the frequency domain of EEG signals for ADHD, subtypes and control groups were analyzed and compared using Matlab software. The mean age of the ADHD children's group was 8.7 years and the control group 9.1 years.Results: Spectral analysis of mean power (μV2) and relative-mean power (%) was carried out for four different frequency bands: delta (0--4 Hz), theta (4--8 Hz), alpha (8--13 Hz) and beta (13--32 Hz). The ADHD and subtypes of ADHD-I, and ADHD-C groups had higher average power value of delta and theta band than that of control group. However, this is not the case for alpha and beta bands. Increases in delta/beta ratio and statistical significance were found only between ADHD-I and control group, and in delta/beta, theta/delta ratio statistical significance values were found to exist between ADHD-C and control group.Conclusion: EEG analyzes can be used as an alternative method when ADHD subgroups are identified.

Global and local grey matter reductions in boys with ADHD combined type and ADHD inattentive type

Attention-deficit/hyperactivity disorder (ADHD) has reliably been associated with global grey matter reductions but local alterations are largely inconsistent with perhaps the exception of the caudate nucleus. The aim of this study was to examine local and global brain volume differences between typically developing children (TD) and children with a diagnosis of ADHD. We also addressed whether these parameters would differ between children with the ADHD-combined type (ADHD-C) and those with the ADHD-inattentive type (ADHD-I). Using an ROI approach caudate volume differences were also examined. 79 boys between the ages of 8 and 17 participated in the study. Of those 33 met diagnostic criteria for the ADHD-C and 15 for the ADHD-I subtype. 31 boys were included in the TD group. Structural magnetic resonance imaging data were analysed using voxel-based morphometry. The ADHD group had significantly lower global and local grey matter volumes within clusters in the bilateral frontal, right parietal and right temporal regions compared to TD. A significant group by age interaction was found for right caudate nucleus volume. No differences between the ADHD-C and ADHD-I groups were found. Right caudate nucleus volume and age are more strongly related in ADHD than in TD consistent with previous research.

Altered structural connectivity is related to attention deficit/hyperactivity subtypes: A DTI study

This study aimed to provide novel insights into the white matter (WM) microstructural properties of Attention Deficit/Hyperactivity Disorder (ADHD) subtypes by recruiting a relatively large sample of stimulant-naïve children and adolescents who had no comorbidity other than Oppositional Defiant Disorder and were homogenous according to the DAT1 gene polymorphism. A sample of 72 ADHD subjects and 24 controls aged 8–15 years were enrolled in the study. We applied tract-based spatial statistics to the DTI measures for obtaining fractional anisotropy (FA) and axial, radial diffusivity (AD, RD) measures to explore ADHD type-related differences in WM for the whole brain. Comparing ADHD-Combined group (ADHD-C) with the ADHD predominantly inattentive group (ADHD-I) we detected increased RD in several bilateral brain area and increased AD mostly in left side of the brain, including the body and splenium of the corpus callosum; the anterior and posteriors limbs of the internal capsule; the superior, anterior and posterior corona radiata; the posterior thalamic radiation; and the superior longitudinal fasciculus. Likewise, mostly in the overlapping brain areas, the ADHD-C group presented increased AD values than ADHD-RI. Significant differences among ADHD types could be a preliminary evidence that they have distinct microstructural properties. There were no significant differences in diffusivity between controls and both the ADHD group as whole or any ADHD subgroups.

Clinical Effects of ADHD Subtypes in Patients With Social Anxiety Disorder

Objective: Our aim in this study is to evaluate the impacts of inattentive and combined types of childhood ADHD (ADHD-I, ADHD-C) in patients with social anxiety disorder (SAD). Methods: A total of 142 adult outpatients with a primary diagnosis of SAD were included. All patients were assessed by using the Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-I), Schedule for Affective Disorders and Schizophrenia for School Age Children–Present and Lifetime Version (K-SADS-PL), ADHD module and a clinical and sociodemographic data form and scales were filled out. Results: Childhood ADHD comorbidity rates was found to be 88 (62%) in patients with SAD, and 63 of these patients had the diagnosis of ADHD-I. ADHD-I group had higher scores of social anxiety and avoidance and had earlier onset of SAD than the ADHD-C group. Conclusion: The inattentive subtype of ADHD may have a more specific relationship with SAD than ADHD-C.

Executive Functioning in Subtypes of Attention Deficit Hyperactivity Disorder.

This study aims to evaluate executive functions (EF), such as inhibition, planning, working memory, and set shifting, in children with attention deficit hyperactivity disorder (ADHD) by comparing three ADHD subtype groups (ADHD-Inattentive, ADHD-Combined, and ADHD-Comorbid) and a normal control group. Participants included 147 children. In total, 111 children were assigned to the ADHD groups of the study. Each child was matched according to the WISC-R Full-Scale IQ-score, sex, and age and was grouped as follows: ADHD-Inattentive group (ADHD-I; n=37), ADHD-Combined (ADHD-C; n=37), ADHD-Comorbid group (ADHD-Comorbid with oppositional defiant disorder and/or conduct disorder; n=37), and control group (n=36). The tests used to assess the children were Conners' Parent and Teacher Rating Scales; Wechsler Intelligence Scale-Revised; Tower of London test; Wisconsin Card Sorting Test; Stroop Color-Word Test, and verbal fluency test. The data were analyzed by one-way ANOVA between subjects for all dependent variables. Children in the ADHD-I group had significantly better performances in verbal working memory and verbal category shifting than children in the ADHD-C group. There was no significant difference between the ADHD-I and ADHD-C groups in terms of inhibition, set shifting, verbal fluency, cognitive flexibility, and planning. The ADHD-Comorbid group displayed more severe impairments in EF measures than the ADHD-C group; however, the severity was not statistically significant. EF performances of children in the control group were similar to children in the ADHD-I group but better than children in the ADHD-C and ADHD-Comorbid groups. The outcome of the study indicated that subjects in the ADHD-Comorbid and ADHD-C groups had more severe EF deficits than subjects in the ADHD-I and control groups.

Family Functioning, Comorbidities, and Behavioral Profiles of Children With ADHD and Disruptive Mood Dysregulation Disorder

Objective: Children with ADHD-combined type (ADHD-C), disruptive mood dysregulation disorder (DMDD), and healthy controls (HC) were compared with respect to the sociodemographic features, psychiatric comorbidities, behavioral patterns, and family functioning. Method: Research groups were identified using the Schedule for Affective Disorders and Schizophrenia for School-Age Children–Present and Lifetime Version (K-SADS-PL). Conners’ Rating Scale–Revised Long Form, Wechsler Intelligence Scale for Children–Revised (WISC-R) test, Sociodemographic Questionnaire, and Family Assessment Device (FAD) were administered to research groups. Results: DMDD group’s rate of psychiatric comorbidity was higher than the ADHD-C group’s rate. In most of the subscales of Conners, DMDD group’s average scores were higher than the other groups’ scores. In “Communication,” “Affective Responsiveness” subscales of FAD, DMDD group’s average scores were higher than the ADHD-C group’s scores. In “Affective Involvement,” “General Functioning” subscales of FAD, DMDD group’s average scores were higher than the other groups’ scores. Conclusion: Children with DMDD were distinguished from children with ADHD-C by their higher comorbidity rate, more impaired behavioral patterns, and family functioning.

Autobiographical memory in ADHD subtypes

Background Episodic autobiographical memory (EAM) has not been extensively investigated in children with attention-deficit/hyperactivity disorder (ADHD). The objective of this study was to examine EAM in school-age children with ADHD in reference to the encoding period: recent memories (previous school years) and remote memories (first years of life).Methods A sample of 29 children with ADHD and 29 typically developing children, matched for age and gender, completed a questionnaire to assess EAM. These participants were recruited from an initial sample of 572 participants. Developmental differences in accessing and recalling specific personal events and episodic details in groups with ADHD were predicted.Results The control group showed a typical trend of EAM with fewer remote and episodic memories than recent ones. The ADHD groups showed a general EAM deficit. More precisely, the ADHD-I group performed equally poorly on remote and recent EAMs, whereas the ADHD-C group showed a higher number of remote EAMs than recent ones.Conclusions The findings suggest that EAM can be impaired in children with ADHD. Clinical and medicolegal implications of these results and the relation between age and childhood amnesia are discussed.

EEG spectral analysis of attention in ADHD: implications for neurofeedback training?

Objective: In children with attention-deficit/hyperactivity disorder (ADHD), an increased theta/beta ratio in the resting EEG typically serves as a rationale to conduct theta/beta neurofeedback (NF) training. However, this finding is increasingly challenged. As NF may rather target an active than a passive state, we studied the EEG in a condition that requires attention.Methods: In children with ADHD of the DSM-IV combined type (ADHD-C; N = 15) and of the predominantly inattentive type (ADHD-I; N = 9) and in typically developing children (N = 19), EEG spectral analysis was conducted for segments during the attention network test (ANT) without processing of stimuli and overt behavior. Frontal (F3, Fz, F4), central (C3, Cz, C4) and parietal (P3, Pz, P4) electrodes were included in the statistical analysis. To investigate if EEG spectral parameters are related to performance measures, correlation coefficients were calculated.Results: Particularly in the ADHD-C group, higher theta and alpha activity was found with the most prominent effect in the upper-theta/lower-alpha (5.5–10.5 Hz) range. In the ADHD-I group, a significantly higher theta/beta ratio was observed at single electrodes (F3, Fz) and a tendency for a higher theta/beta ratio when considering all electrodes (large effect size). Higher 5.5–10.5 Hz activity was associated with higher reaction time variability with the effect most prominent in the ADHD-C group. A higher theta/beta ratio was associated with higher reaction times, particularly in the ADHD-I group.Conclusions: (1) In an attention demanding period, children with ADHD are characterized by an underactivated state in the EEG with subtype-specific differences. (2) The functional relevance of related EEG parameters is indicated by associations with performance (reaction time) measures. (3) Findings provide a rationale for applying NF protocols targeting theta (and alpha) activity and the theta/beta ratio in subgroups of children with ADHD.

Differential perinatal risk factors in children with attention-deficit/hyperactivity disorder by subtype

We compared the attention-deficit/hyperactivity disorder(ADHD) combined subtype (ADHD-C) to the ADHD inattentive subtype (ADHD-I) in terms of genetic, perinatal, and developmental risk factors as well as clinical and neuropsychological characteristics. A total of 147 children diagnosed with ADHD between the ages of 6 and 15 years participated in this study. The parents of the children completed the structured diagnostic interview, the ADHD Rating Scale-IV, the Children’s Behavior Checklist, and structured questionnaires on perinatal risk factors, and the children underwent a neuropsychological test and were genotyped. A total of 502 children without ADHD were recruited from the community as a healthy control group. The ADHD-C children showed more severe externalizing symptoms, showed more deficits in a continuous performance test, and were more likely to have comorbid disorders. Maternal stress during pregnancy, postpartum depression, and changes in the primary caretaker during first 3 years were significantly associated with both ADHD-I and ADHD-C. The ADHD-I group was less likely to have received regular prenatal check-ups and more likely to have had postnatal medical illness than the ADHD-C group. There were no significant differences in the genotype frequencies of the dopamine transporter (DAT1) and the serotonin transporter –linked polymorphic region (5-HTTLPR) polymorphisms between ADHD-I and ADHD-C groups. This study shows that the inattentive subtype of ADHD is different from the combined subtype in many parameters including severity of symptoms, comorbidity, neuropsychological characteristics, and environmental risk factors.

Differentiating Between Comorbidity and Symptom Overlap in ADHD and Early Onset Bipolar Disorder

Reported rates of comorbidity between early onset bipolar disorder (BD) and attention deficit hyperactivity disorder (ADHD) have a wide range, perhaps due to developmental issues and differences in interpretation of overlapping symptoms. We compared questionnaire-based and neuropsychological measures of inattention and impulsivity/hyperactivity, in children/adolescents with ADHD combined subtype (ADHD-C; n26), concurrent ADHD-C and BD (n15), BD (n25) with Controls (n69). Sub-analyses were performed on BD with and without inattention symptoms. The two ADHD-C groups displayed neuropsychological impairments that were not found in the BD group in spite of subjective and questionnaire-rated inattention. The findings caution against over-diagnosis of ADHD in BD.

Comparison of neuropsychological performances and behavioral patterns of children with attention deficit hyperactivity disorder and severe mood dysregulation

We aimed to investigate the similarities and differences in neuropsychological test performance, demographic features and behavioral patterns of children and adolescents with the attention deficit hyperactivity disorder combined type (ADHD-C), and the severe mood dysregulation (SMD). Study includes 112 children: 67 with ADHD-C, 24 with SMD and 21 healthy controls. These groups were identified by using the schedule for affective disorders, and schizophrenia for the school-age children-present and lifetime version (KSADS-PL) and the K-SADS-PL-SMD Module. Conners' Parent and Teacher Rating Scale-revised long form (CPRS-R:L and CTRS-R:L) and neuropsychological tests were administered to the research groups. ADHD-C group's performances in Wisconsin Card Sorting Test, Trail Making Test, Stroop Test TBAG form and Controlled Oral Word Association Test were significantly poorer than the control group's performances (p < 0.05). Performance of the SMD group was only descriptively intermediate between performances of the ADHD-C and control group. In the "Oppositional", "Hyperactivity", "Social Problems", "Impulsive", "Emotional Lability" and "Conners' Global Index" subscales of CPRS-R:L, the average scores of the SMD group were significantly higher than the ADHD-C and control group's average scores (p < 0.05). ADHD-C group (but not SMD) could be significantly differentiated from healthy controls with the neuropsychological tests used. SMD group could be differentiated from the ADHD-C and healthy control groups with CPRS-R:L; i.e., ADHD-C versus SMD could be differentiated at the behavioral level only.

Onset Time of Binocular Rivalry and Duration of Inter-Dominance Periods as Psychophysical Markers of ADHD

Attention deficit hyperactivity disorder (ADHD) is one of the main neurobiological disorders in young children. Despite its prevalence, current diagnosis is debated. In this study we tested whether measures of binocular rivalry (BR) can contribute to the diagnosis of ADHD. BR is a phenomenon that is produced when two different images are presented to the two eyes simultaneously. Under these conditions the image presented to one eye competes with that presented to the other eye in seeking to achieve perceptual dominance. This competition is resolved through the activation of a given percept coupled with the suppression of the percept that had predominated until that point. We assume that the difficulty with inhibiting responses of ADHD children also affects their ability to inhibit the dominant image in a BR context. We analyzed the time to rivalry onset and the inter-dominance periods as measures of the temporal cost of resolving how long it takes for the brain to select (or suppress) one percept over the other. Our results show that the time to onset of rivalry (the first dominance) was longer in the clinical groups (ADHD-C and ADHD-I) than in the control group. As regards the inter-dominance periods, these were longer in the ADHD-C group than among controls, with the shortest period corresponding to the ADHD-I group. This study shows that BR can be used as a tool to develop a behavioral indicator of ADHD.

Differences in cognitive control in children and adolescents with combined and inattentive subtypes of ADHD

The aim of the present study was to investigate the ability of children with attention deficit/hyperactivity disorder-combined subtype (ADHD-C) and predominantly inattentive subtype (ADHD-PI) to direct their attention and to exert cognitive control in a forced attention dichotic listening (DL) task. Twenty-nine, medication-naive participants with ADHD-C, 42 with ADHD-PI, and 40 matched healthy controls (HC) between 9 and 16 years were assessed. In the DL task, two different auditory stimuli (syllables) are presented simultaneously, one in each ear. The participants are asked to report the syllable they hear on each trial with no instruction on focus of attention or to explicitly focus attention and to report either the right- or left-ear syllable. The DL procedure is presumed to reflect different cognitive processes: perception (nonforced condition/NF), attention (forced-right condition/FR), and cognitive control (forced-left condition/FL). As expected, all three groups had normal perception and attention. The children and adolescents with ADHD-PI showed a significant right-ear advantage also during the FL condition, while the children and adolescents in the ADHD-C group showed a no-ear advantage and the HC showed a significant left-ear advantage in the FL condition. This suggests that the ADHD subtypes differ in degree of cognitive control impairment. Our results may have implications for further conceptualization, diagnostics, and treatment of ADHD subtypes.

Time course of the development of depressive mood and oppositional defiant behavior among boys with attention deficit hyperactivity disorder: Differences between subtypes

The aim of this research was to clarify the development of depression among boys with attention deficit hyperactivity disorder (ADHD) by examining the correlation between depressive mood, oppositional defiant behavior, and age for each ADHD subtype. The Birleson Depression Self-Rating Scale (DSRS) was used to evaluate depressive mood while the Oppositional Defiant Behavior Inventory (ODBI) was used to evaluate oppositional defiant behavior. The 90 subjects were divided into three groups: 22 boys (mean age, 12.4 ± 1.9 years) were placed in the ADHD predominantly inattentive type (ADHD-I) group; 45 boys (mean age, 10.4 ± 2.0 years) were placed in the ADHD combined type (ADHD-C) group; and 23 boys (mean age, 12.7 ± 2.4 years) were placed in the depressive disorder (DD) group. The DD group was included to highlight characteristics of depressive mood among boys with ADHD. The DSRS score was significantly higher in the DD group compared to the ADHD-I and ADHD-C groups. The ODBI score was significantly higher in the ADHD-C group compared to the ADHD-I (P = 0.043) and DD (P = 0.013) groups. In the DD group, ODBI was seen to decrease with increasing age. A certain degree of oppositional defiant behavior was seen in each ADHD subtype. The DSRS score correlated with the ODBI score in the ADHD-C group, while the DSRS score correlated with age in the ADHD-I group. The characteristics of developing depressive mood in childhood ADHD appeared to differ between subtypes and also differed from depression without ADHD.

Memory in Early Onset Bipolar Disorder and Attention-Deficit/Hyperactivity Disorder: Similarities and Differences

Differentiating between early-onset bipolar disorder (BD) and attention-deficit/hyperactivity disorder (ADHD) can be difficult. Memory problems are commonly reported in BD, and forgetfulness is among the diagnostic criteria for ADHD. We compared children and adolescents with BD (n = 23), ADHD combined type (ADHD-C; n = 26), BD + ADHD-C (n = 15), and 68 healthy controls on memory tests (Digit span, Children's Verbal Learning Test-II). Further analyses were performed on subgroups of BD (BD-I, BD-II/BD-NOS, with and without previous psychotic symptoms). All clinical groups demonstrated some problems with free recall, but the BD subgroup with a history of psychotic symptoms had a more pervasive problem that also included recognition and semantic clustering. The ADHD-C groups demonstrated the lowest performance on working memory. These data suggest that children and adolescents with BD and previously psychotic symptoms may have inefficient encoding of verbal material, whereas memory problems in ADHD-C appear more characterized by impaired free recall.

Divergence by ADHD Subtype in Smoking Cessation Response to OROS-Methylphenidate

Attention deficit hyperactivity disorder (ADHD) is a neuropsychiatric condition subclassified in DSM-IV according to its core symptoms domains as (a) predominantly inattentive (ADHD-IN), (b) predominantly hyperactive/impulsive (ADHD-H), and (c) combined inattentive and hyperactive/impulsive (ADHD-C). Whether these subtypes represent distinct clinical entities or points on a severity continuum is controversial. Divergence in treatment response is a potential indicator of qualitative heterogeneity. This study examined smoking cessation response by ADHD subtype to osmotic-release oral system methylphenidate (OROS-MPH). Male and female adult smokers (ADHD-C = 167 and ADHD-IN = 87) were randomized to receive OROS-MPH or placebo as augmentation treatment to nicotine patch and counseling. Logistic regression was conducted to test the effect of OROS-MPH versus placebo on prolonged smoking abstinence by ADHD subtype. The subtypes were similar in baseline demographic, smoking, and psychiatric history but differed in smoking cessation response to OROS-MPH or placebo as a function of nicotine dependence level. The 3-way interaction was significant; χ(2)(1) = 8.22, p < .01. Among highly dependent smokers, the prolonged abstinence rates were greater with OROS-MPH than with placebo in the ADHD-C group (60% vs. 31.3%, respectively, p < .05) but higher with placebo than with OROS-MPH in the ADHD-IN group (60% vs. 11.8%, respectively, p < .01). Abstinence rates did not differ by subtype or treatment among smokers who were less nicotine dependent. Contrasting treatment response and divergence in the impact of nicotine dependence level support the hypothesis of ADHD subtypes as distinct clinical entities and may indicate the need and directions for personalized targeted treatments of smokers with ADHD.

The function of hypothalamus–pituitary–adrenal axis in children with ADHD

Objective:To explore the relationship between hypothalamus–pituitary–adrenal (HPA) axis and Attention Deficit Hyperactivity Disorder (ADHD) in non-stress states. Method: 128 male children with ADHD aged between 6 and 14 years old were recruited, while 30 healthy male children were chosen as a control group. The diagnostic material was based on DSM-IV. The included ADHD children were further classified into the three sub-groups: ADHD-predominantly inattention type (ADHD-I) ( n = 44), ADHD-predominantly hyperactive impulsive type (ADHD-HI) ( n = 32), and ADHD-combined type (ADHD-C) ( n = 52). The levels of cortisol and adrenocorticotropin hormone (ACTH) were evaluated by the automatic particle enzyme immunoassay and electrochemiluminescence respectively per morning (8:00 am). Intelligence test was assessed by the Raven's Standard Progressive Matrices. Results: The children with ADHD had significantly lower intelligence quotient (IQ) (84.5 ± 11.3) in contrast to the control group (98.6 ± 12.4, P < 0.01), although the lower level of IQ in ADHD-C group (79.2 ± 10.7) was also found when compared with other two sub-groups [ADHD-I (85.6 ± 10.4) and ADHD-HI (91.3 ± 12.6)]. In addition, no significant difference between the ADHD-HI group and the control group regarding the level of IQ were revealed. The level of cortisol in the ADHD group (226.47 ± 129.12 nmol/L) was significantly lower than that of the control group (384.53 ± 141.43 nmol/L, P < 0.001). The level of cortisol of the ADHD-HI group (154.36 ± 71.62 nmol/L) was significantly lower than that of other two groups [ADHD-I group (219.42 ± 117.66 nmol/L) ( P < 0.01) and ADHD-C group (258.30 ± 136.39 nmol/L) ( P < 0.01)]. There were no significant differences in the ACTH level either between the ADHD and the control group ( P > 0.05), or between sub-groups in ADHD ( P > 0.05). Conclusion: In the non-stress states, the existence of dysfunction of the HPA axis (lower plasma cortisol) in children with ADHD might be due to the under-reactivity of the HPA axis ; the low plasma cortisol level might contribute less to the outcomes of cognitive behavior of ADHD children and instead more closely relate to the core domains of attention deficit, hyperactivity and impulsive behavior of ADHD patients.

Executive dysfunction screening and intelectual coefficient measurement in children with attention deficit hyperactivity disorder

To perform a complete Intelligence quotient (IQ) measurement (verbal, performance, and total) and subsequently, to compare executive function (EF) measurements in subgroups of children with attention deficit-hyperactivity disorder (ADHD) with a control group. We studied a group of children from 7-12 years of age from public elementary schools. Children were selected by means of Diagnostic and Statistical Manual of Mental Disorders-IV-Revised (DSM-IV-R) parent and teacher questionnaires for ADHD. EFs were screened by Weschler Intelligence Scale for Children (WISC-R) performance intelligence quotient (IQ) determination of the following sub-tests: picture completion; block designs, and object assembly tests. Simultaneously, total (T-), performance (P-), and verbal (V-) IQs were measured for each patient. We studied 26 control subjects, and 35 children with ADHD. Numbers of children in each ADHD sub-type group were as follows: 15 in the combined group (-C), 13 in the inattentive group (-I), and 7 in hyperactivity group (-H). We found significant lower EF scores in picture arrangement (F=3.76, df 3,57, p=0.01), block design (F=4.55, df 3,57, p<0.01), and object assembly (F=4.52, df 3,57, p<0.01). Post-hoc analysis showed that differences were located among ADHD-C, ADHD-I, and ADHD-H groups when compared with controls. We found significantly lower cognitive scores in the ADHD-I group as follows: P-IQ (F=3.57, df 3,57, p=0.02), and T-IQ (F=2.90, df 3,57, p=0.04). Our results showed that screening of EF alteration in children with ADHD is easy and rapid by means of certain P-IQ determination sub-scales of the WISC test; moreover, complementary IQ determination can be measured simultaneously. Overall, children with ADHD exhibited an EF alteration. ADHD-I children demonstrated lower P-IQ, and T-IQ scores than control children.

Association between symptoms and subtypes of attention-deficit hyperactivity disorder and sleep problems/disorders

This study aimed to investigate the association between attention-deficit hyperactivity disorder (ADHD) symptoms and subtypes, and sleep schedules, daytime inadvertent napping, and sleep problems/disorders in children and adolescents with and without ADHD. The sample included 325 patients with ADHD, aged 10-17 years [male: 81.5%; combined type (ADHD-C): 174; predominantly inattentive type (ADHD-I): 130; predominantly hyperactive-impulsive type (ADHD-HI): 21], and 257 children and adolescents without lifetime ADHD (non-ADHD). We conducted psychiatric interviews with the participants and their mothers before making the diagnoses of ADHD, other psychiatric disorders, and sleep problems or disorders. We also collected the medication treatment data and parent and teacher reports of ADHD symptoms. Multi-level models were used for data analyses controlling for sex, age, psychiatric comorbidities, and treatment with methylphenidate. The ADHD-C and ADHD-I groups had more daytime inadvertent napping. In general, the three subtypes were associated with increased rates of sleep problems/disorders. Specifically, ADHD-C rather than ADHD-I was associated with circadian rhythm problems, sleep-talking, nightmares (also ADHD-HI), and ADHD-I was associated with hypersomnia. The most-related sleep schedules and problems for inattention and hyperactivity-impulsivity were earlier bedtime, later rise time, longer nocturnal sleep, more frequent daytime napping, insomnia, sleep terrors, sleep-talking, snoring, and bruxism across informants. The findings imply that in addition to the dichotomous approach of ADHD and considering the psychiatric comorbid conditions, ADHD subtypes and symptom dimensions need to be considered in clinical practice and in the research regarding the association between ADHD and sleep problems/disorders.