Objective measurement of attention deficit hyperactivity disorder symptoms outside the clinic using the QbCheck: Reliability and validity

Objective measurements of ADHD symptom levels can be a highly valuable complement to ratings. However, sometimes it is not feasible to bring patients into the clinic/lab for assessment. The aim of the present study was therefore to evaluate the psychometric properties of the QbCheck, an online computerized test that measures errors and reaction time as well as activity during testing using the computer's built‐in web camera. Study I (n = 27 adolescents/adults) investigated test–retest reliability and concurrent validity of the QbCheck. Study II included 142 adolescents/adults (69 with ADHD/73 controls) and investigated convergent and diagnostic validity, as well as usability, of the QbCheck. In Study I, the QbCheck showed high test–retest reliability and high concurrent validity. In Study II, high convergent validity was observed when studying associations between the QbCheck performed in the home and the QbTest performed at the clinic. In addition, the QbCheck discriminated well between patients with ADHD and controls, with a sensitivity of 82.6 and a specificity of 79.5. The QbCheck appears to be a valuable test with good psychometric properties and will thereby enable assessment of ADHD symptom levels in adolescents and adults outside the clinic in the home setting.     

Convergent and divergent validity of K-SADS-PL anxiety and attention deficit hyperactivity disorder diagnoses in a clinical sample of school-aged children

Background The Schedule for Affective Disorders and Schizophrenia for School Age Children, Present and Lifetime Version (K-SADS-PL) is a commonly used diagnostic interview both in research and clinical settings, yet published data on the psychometric properties of the interview generated diagnoses are scarce. Aims To examine the convergent and divergent validity of the Norwegian version of the K-SADS-PL current diagnoses of anxiety disorders and attention deficit hyperactivity disorder (ADHD). Method Participants were 105 children aged 7–13 years referred for treatment at child mental health clinics and 36 controls. Diagnostic status was determined based on K-SADS-PL interviews with the mothers. Child and mother reported child symptoms of anxiety on the Multidimensional Anxiety Scale for Children and teachers reported anxiety symptoms on the Teacher Report Form. Mother and teacher reported on symptoms of ADHD on the Disruptive Behavior Rating Scale. Results Rating scale data from multiple informants in a clinical sample and healthy controls supported the convergent and divergent validity of K-SADS-PL anxiety diagnoses combined, and, specifically, the diagnoses of separation anxiety disorder, social phobia, and specific phobia. Support was also observed for convergent and divergent validity of ADHD diagnoses, including the predominately inattentive subtype. Conclusion The K-SADS-PL generates valid diagnoses of anxiety disorders and ADHD.     

Effectiveness of symptom validity measures in identifying cognitive and behavioral symptom exaggeration in adult attention deficit hyperactivity disorder

This study examines the effectiveness of symptom validity measures to detect suspect effort in cognitive testing and invalid completion of ADHD behavior rating scales in 268 adults referred for ADHD assessment. Patients were diagnosed with ADHD based on cognitive testing, behavior rating scales, and clinical interview. Suspect effort was diagnosed by at least two of the following: failure on embedded and free-standing SVT measures, a score > 2 SD below the ADD population average on tests, failure on an ADHD behavior rating scale validity scale, or a major discrepancy between reported and observed ADHD behaviors. A total of 22% of patients engaged in symptom exaggeration. The Word Memory test immediate recall and consistency score (both 64%), TOVA omission errors (63%) and reaction time variability (54%), CAT-A infrequency scale (58%), and b Test (47%) had good sensitivity as well as at least 90% specificity. Clearly, such measures should be used to help avoid making false positive diagnoses of ADHD.      

Objective measurement of weekly physical activity and sensory modulation problems in children with attention deficit hyperactivity disorder

This study aimed to objectively compare the daily physical activity (PA), as indicated by moderate-to-vigorous physical activity (MVPA) during a week and metabolic equivalents (METs) per minute, between children with attention deficit hyperactivity disorder (ADHD) and typically developing children. Moreover, sensory modulation problems were examined using behavioral and physiological measures. Twenty boys with ADHD (mean age 8.64 ± 2.57 years), and 20 matched typically developing boys (mean age 9.10 ± 1.79 years) participated in our study. Each child wore a PA monitor for 14 h a day, seven days a week. All participants’ parents were asked to fill out daily activity logs for their children. The problems of sensory modulation were detected using sensory profile (SP) questionnaires and Sensory Challenge Protocol that measured electrodermal response (EDR) to repeated sensory stimulation. Compared with the controls, the children with ADHD had a generally higher level of PA (1.48 ± 0.10 vs. 1.60 ± 0.12 METs/min; p = 001), and tended to spend more time in MVPA on weekdays (35.71%) and the weekend (57.14%). However, when analyzing hourly recorded PA, the group differences were obvious only for certain hours. Our data suggested that children with ADHD were more hyperactive in structure-free than structured settings. The ADHD group showed their sensory modulation problems on the SP but not on the EDR. We found some correlations between sensory modulation problems and hyperactivity in children with ADHD.     

Gait in attention deficit hyperactivity disorder

Abstract Background Cognitive function and the loading of attention presumably play an important role in gait as well as in fall risk, but previous work has not demonstrated this in any cause-and-effect way. Objectives To gain insight into the relationship between gait and cognitive function, we sought: (1) To compare the gait rhythmicity (stride time variability) of children with attention deficit hyperactivity disorder (ADHD) to controls, (2) To test the hypothesis that dual tasking leads to increased stride-to-stride variability in ADHD, and (3) To test whether pharmacological treatment that relieves ADHD symptoms reduces stride-to-stride variability. Patients and Methods Gait was quantified in children with ADHD and in age-matched healthy controls under single task and dual task conditions on three occasions: off medications (both groups) and, in the ADHD group, after double blinded, randomized administration of methylphenidate (MPH) or placebo. Results At baseline, children with ADHD tended to walk with increased stride-to-stride variability compared to the controls during the single task condition (p = 0.09). During dual task walking, stride time variability was significantly reduced in the children with ADHD (p < 0.004), but not in the controls. In the children with ADHD, the placebo did not significantly affect stride-to-stride variability or the dual tasking response. In contrast, stride time variability was significantly reduced on MPH (p < 0.001) such that dual tasking no longer affected variability. Conclusions The present findings demonstrate alterations in the gait of children with ADHD, support a cause and effect link between cognitive function and gait, and suggest that enhancement of attention abilities may, in certain populations, improve gait rhythmicity.     

Schizotypy, attention deficit hyperactivity disorder, and dopamine genes

Previous research has suggested that there may be overlap between schizophrenia and attention-deficit hyperactivity disorder (ADHD). The relationship between schizotypal personality traits, ADHD features and polymorphisms was evaluated in dopamine-related genes. Thirty-one healthy, Caucasian men completed the Rust Inventory of Schizotypal Cognitions (RISC) and the ADHD Self-Report Scale (ASRS). Catechol-O-methyltransferase (COMT) Val158Met, dopamine receptors of the D3 type (DRD3) Ser9Gly, DRD4 variable number of tandem repeats (VNTR), and SLC6A3 VNTR polymorphisms were analyzed. RISC score was correlated with ASRS score (r = 0.54, P = 0.003). COMT Met homozygotes had higher ASRS scores than Val homozygotes (P = 0.005). These findings are consistent with evidence of overlap between schizophrenia and ADHD and support an involvement of COMT genotype in ADHD features.     

Transferrin in korean children with attention deficit hyperactivity disorder

Objective

The aim of the present study was to investigate the relationship between iron, ferritin, transferrin, total iron binding capacity (TIBC), hemoglobin, mean corpuscular volume (MCV) mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) in children with ADHD.

Methods

MethodsaaThe sample consisted of 48 ADHD children and sex and age matched control children (a couple of 28 boys, 22 girls; age 6-8 years; mean±SD, 6.98±0.39). We diagnosed ADHD according to DSM-IV. ADHD symptoms were evaluated subjectively with Conners'' Parent Rating Scales, Dupaul Parent ADHD Rating Scales. Subjects with ADHD and control were evaluated the hematology test including the iron, transferrin, MCV etc. Paired t test were used to evaluate the relation of a lot of hematology findings between ADHD and control group.

Results

The serum iron, ferritin, transferrin, TIBC, hemoglobin, MCV, MCH, and MCHC of ADHD group were respectively 80.92±33.33 ug/dL, 35.81±16.59 ng/mL, 248.42±44.15 mg/dL, 351.69±102.13 ug/dL, 12.78±0.71 g/dL, 82.94±2.58 fL, 27.18±1.12 uug, 32.79±1.12%. Otherwise the serum iron, ferritin, transferrin, TIBC, hemoglobin, MCV, MCH, and MCHC of control group were respectively 82.04±28.14 ug/dL, 37.05±18.28 ng/mL, 266.27±25.40 mg/dL, 352.77±89.54 ug/dL, 12.77±0.70 g/dL, 81.81±2.96 fL, 26.69±0.99 uug, 32.66±0.96%. A significant difference were found in the transferrin(t=2.63, p=0.011), MCV (t=2.19, p=0.034), and MCH (t=2.18, p=0.034).

Conclusion

These results suggested that lower transferrin levels might be related with ADHD symptoms.     

Hyperfocusing as a dimension of adult attention deficit hyperactivity disorder

Patients with Attention Deficit Hyperactivity Disorder (ADHD) suffer not only from inability to focus but also from inability to shift attention for events that trigger their interests. This phenomenon is called “hyperfocusing”. Previous literature about hyperfocusing is scarce and relies mainly on case reports. The study aimed to investigate and compare the severity of hyperfocusing in adult ADHD with and without psycho-stimulant use. ADHD (DSM-IV-TR) patients either psycho-stimulant naive (n = 53) or on psycho-stimulants (n = 79) from two ADHD clinics were recruited. The control group (n = 65) consisted of healthy university students. A socio-demographic form, the Beck Depression Inventory, the Wender-Utah Rating Scale, the Adult ADHD Self- Report Scale and the Hyperfocusing Scale were applied to the participants. There was no difference between total Hyperfocusing Scale and Adult ADHD Self- Report Scale scores of two patient groups, but both have higher scores than controls (p < 0.001). Hyperfocusing is higher in adult ADHD and there was no difference between stimulant-naive patients or patients on stimulants. Hyperfocusing can be defined as a separate dimension of adult ADHD.     

Parent ratings of school behaviour in children at risk of attention deficit/hyperactivity disorder

OBJECTIVE: To investigate whether parents are accurate informants of child hyperactivity symptoms and impairment at school. METHOD: Parents of a community sample of 93 children with pervasive hyperactivity completed rating scales about their child's behaviour at home and school. These were compared with teacher ratings. RESULTS: Parent ratings about school correlate more closely with parent (home) than teacher ratings. Such ratings systematically under-estimate teacher ratings and are influenced by the child's behaviour at both home and school as well as parental mental health. However, a parental report of impairment for the child at school is likely to be accurate. CONCLUSION: There are limitations in relying on parental accounts of school behaviour if teacher ratings are unavailable. As such ratings may under-identify children with ADHD and discrepancies between parent and teacher ratings may reflect actual differences in behaviour, this suggests that ratings are required from both sets of informants.     

The fMRI success rate of children and adolescents: Typical development,epilepsy, attention deficit/hyperactivity disorder,and autism spectrum disorders

Functional magnetic resonance imaging (fMRI) in children is increasingly used in clinical application and in developmental research; however, little is known how pediatric patient and typically developing populations successfully complete studies. We examined pediatric success rates with epilepsy, attention deficit/hyperactivity disorder (ADHD), autism spectrum disorders (ASD), and typically developing children (TYP). We also examined the affect of age, and, for ADHD populations, medication status on success rates. We defined a successful fMRI individual run when the data were interpretable and included in group statistics. For unsuccessful runs, datasets with excessive motion or floor task performance were categorized when possible. All clinical groups scanned less successfully than controls; medication status did not affect ADHD success (epilepsy, 80%; ADHD (off methylphenidate), 77%; ADHD (on methylphenidate), 81%; ASD, 70%; TYP, 87%). Ten to 18‐year‐old had a significantly greater scan success rate than 4‐ to 6‐year‐old; adolescents (13‐ to 18‐year‐old) demonstrated greater scan success rates than 7‐ to 9‐year‐old. Success rate for completing an entire battery of experimental runs (n = 2–6), varied between 50–59% for patient populations and 69% for TYP (79% when excluding 4‐ to 6‐year‐old). Success rate for completing one run from a battery was greater than 90% for all groups, except for ASD (81%). These data suggest 20–30% more children should be recruited in these patient groups, but only 10–20% for TYP for research studies. Studies with 4‐ to 6‐year‐olds may require 20–40% additional participants; studies with 10‐ to 18‐year‐olds may require 10–15% additional participants. Hum Brain Mapp, 2009. © 2009 Wiley‐Liss, Inc.     

H-MR-spectroscopy of cerebellum in adult attention deficit/hyperactivity disorder

Introduction

Neurobiological research has implicated the cerebellum as one possible site of neurophysiological dysfunction in ADHD. Latest theoretical conceptualizations of the cerebellum as core site of the brain to model motor as well as cognitive behavior puts further weight to the assumption that it might play a key role in ADHD pathophysiology.

Methods

30 medication free adult ADHD patients and 30 group matched (gender, age and education) healthy controls were investigated using the method of chemical shift imaging (CSI) of the cerebellum. The vermis, left and right cerebellar hemispheres were processed separately.

Results

We found significantly increased glutamate-glutamine (Glx) to creatine (Cre) ratios in the left cerebellar hemisphere. No other differences in measured metabolite concentrations were observed.

Discussion

To our knowledge this is the first evidence for neurochemical alterations in cerebellar neurochemistry in adult ADHD. They relate well to recent hypotheses that the cerebellum might control mental activities by internal models.     

Smell identification function in children with attention deficit hyperactivity disorder

Objective

Deficits in olfactory function are common features in neurodegenerative and neuropsychiatric disorders. Olfactory processing is related to dopamine metabolism and orbitofrontal cortex functioning, both known to be involved in the neurobiology of ADHD. Some investigations suggested alterations in olfactory processing (identification and detection threshold) in patients with ADHD. Despite increasing knowledge, controversy about this topic still exists regarding children with ADHD. This study was conducted to help elucidate some of this controversy.

Methods

50 participants (8-15 years, mean=10.70±1.77) with ADHD were compared to 50 controls. The two groups were well matched for age, gender and Mean School Scores (MSS). We assessed odor identification and threshold through a smell test composed of two tests of identification and detection threshold. Odor detection threshold was assessed with the odorant phenyl ethyl alcohol solved in propylene glycol using a single staircase method. Odor identification was assessed with chemical essences of five common odorants.

Results

The mean Sensory Identification Score for children with ADHD and the control groups were 3.76 (1.06) and 4.46 (0.76), respectively (p<0.001). The mean for Sensory Threshold Score for ADHD and control group was 6.4 (3.35) and 9.75 (2.16), respectively (p<0.001).

Conclusion

This study replicated altered olfactory performance in ADHD. Substantial olfactory deficits across the two domains of identification and detection threshold are observed in children with ADHD. These deficits do not seem to be a result of olfactory task difficulty and are not influenced by age, gender and MSS. Further studies are required to investigate whether olfactory function can be used as a biological marker for early diagnosis, treatment and prognosis of ADHD.     

State-related electroencephalographic deviances in attention deficit hyperactivity disorder

This study investigated the stability and state-related characteristics of electroencephalographic (EEG) deviances in attention-deficit/hyperactivity disorder (ADHD). Three minutes resting EEG with eyes closed and eyes open were compared between 21 children with ADHD and 29 typically developing children. Across resting conditions, children with ADHD exhibited divergent topographic distribution for theta, alpha and beta power compared to typically developing children. In addition, less alpha and theta suppression to eye opening was found in children with ADHD, but only in those without comorbid ODD/CD. Findings of the present study refer to a consistent divergence in topographic distribution in ADHD across resting state conditions, yet demonstrate that state-related factors and comorbidity may also contribute to resting EEG deviances in ADHD. The state-related findings are in accord with several theoretical accounts emphasizing the role of contextual and state factors defining deficits in ADHD.     

Differential reward processing in subtypes of adult attention deficit hyperactivity disorder

Objectives

Abnormalities in reward processing have been found in adolescents and adults with ADHD using the ‘Monetary Incentive Delay’ (MID) task. However, ADHD groups in previous studies were heterogeneous regarding ADHD subtype, gender and, in part, drug treatment status.This study sought to compare neural activations in the ventral striatum (VS) and prefrontal regions during reward processing in homogenous ADHD subtype groups and healthy adults, using the MID task.

Methods

In total, 24 drug-naïve, right-handed male adults with ADHD (12 subjects with combined type (ADHD-ct) and 12 subjects with predominantly inattentive (ADHD-it) type ADHD), and twelve healthy right-handed male control subjects were included.

Results

Compared to ADHD-ct and healthy subjects, ADHD-it subjects showed a bilateral ventral striatal deficit during reward anticipation. In contrast, ADHD-ct subjects showed orbitofrontal hyporesponsiveness to reward feedback when compared with ADHD-it and healthy subjects.

Conclusions

This is the first fMRI study that delineates dysfunctional and subtype-divergent neural and behavioural reward processing in adults with ADHD.     

Evaluation of adult attention deficit hyperactivity disorder in smokers and Maras powder users

Abstract

Background: The aim of this study was to evaluate adult attention deficit and hyperactivity disorder (ADHD) in smokers, Maras powder users and non-users of tobacco products by using the Adult Attention Deficit and Hyperactivity Disorder Self-report Scale (ASRS). Methods: The study was performed on 446 males presenting to family health centers in Kahramanmara, Turkey. Of 446 participants, 104 were Maras powder users, 133 were smokers and 209 were volunteers not using any tobacco products. Data were collected with a questionnaire composed of questions about socio-demographic features and features of smoking and Maras powder use, and the Fagerström Nicotine Dependence Scale and the ASRS. P < 0.05 was considered significant. Results: The mean age of the participants was 33.94 ± 10.68 years (min = 18, max = 64). There was no significant difference in age between the study groups (P = 0.089). Thirty-one participants (7.0%) received scores higher than the cut-off value (≥ 14 points) for the short form of the ASRS. Twenty-one participants (4.7%) achieverd scores higher than the cut-off value (≥ 44 points) for the ASRS. The smokers received the highest scores of 8.42 ± 3.79 for all the subscales of the short version of the ASRS, 26.87 ± 10.46 for the ASRS, 12.57 ± 6.47 for the attention deficit subscale and 14.30 ± 5.35 for the hyperactivity and impulsivity subscale. Conclusion: Higher rates of the smokers and the Maras powder users had symptoms of ADHD. Considering nicotine may decrease symptoms of ADHD, it can be assumed that the rates of the smokers and Maras powder users with ADHD are higher.     

The role of neuropsychological assessment in adults with attention deficit/hyperactivity disorders

Attention-Deficit Hyperactivity Disorder (ADHD) is a neurodevelopmental disorder characterized by inattention, hyperactivity and/or impulsivity. While ADHD was initially recognized as a childhood syndrome, scientific evidence accumulated to indicate that a significant proportion of ADHD children continue to experience symptoms of ADHD in adulthood. Moreover, the question of ADHD diagnosis can arise in adult patients who were not diagnosed in childhood. Currently, the diagnosis of ADHD in adulthood is based on the revised criteria described for children. However, their application for adults may be difficult for many reasons including compensation and comorbid disorders. To date, no clinical, neuropsychological, biological or imaging marker is available for the diagnosis of ADHD. Considering that ADHD is based on a neuropsychological model, in this article we will examine the usefulness of neuropsychological testing in the diagnosis in adults. We will first present diagnostic criteria of ADHD and the limits of their application in adults. We will then detail the neuropsychological data available in adult ADHD and the French and international clinical recommendations for neuropsychological assessment. Finally, we will explore the predictive value of neuropsychological scores in the diagnosis of ADHD and discuss key methodological points and perspectives for clinical research.     

Dexmethylphenidate hydrochloride in the treatment of attention deficit hyperactivity disorder

Attention-deficit/hyperactivity disorder (ADHD) affects a large number of children. For decades, the stimulants have been the mainstay of pharmacological treatment for ADHD. Dexmethylphenidate (d-MPH), the d-isomer of the traditional racemic mixtures of d,l-threo-(R,R)-MPH, was recently introduced as another potential option in the stimulant class of medications. This paper reviews and summarizes the available research literature on d-MPH regarding pharmacodynamic, pharmacokinetic, chemical structure, receptor binding, toxicology, and clinical perspectives. d-MPH potentially may offer some advantages in the realms of absorption and duration of action compared with its racemic counterpart. The differences in pharmacokinetics and clinical implications of the immediate-release and extended-release forms of d-MPH are also compared and contrasted.     

Ghrelin modulates dopaminergic neuron formation and attention deficit hyperactivity disorder-like behaviors: From animals to human models

Attention deficit hyperactivity disorder (ADHD) is one of the most prevalent psychiatric disorders in children. The orexigenic hormone ghrelin is important in neuroprotection and neurodevelopment, which may play an important role in psychopathogenesis of ADHD. This study aimed to systematically investigate the genomic and pharmacological manipulations of ghrelin functioning in ADHD-like symptoms in zebrafish models and validated the effects of ghrelin polymorphisms in human subjects with ADHD. We firstly generated ghrelin^Δ/Δ zebrafish mutant, which displayed hyperactive, attention deficit-like and impulsive-like behaviors, as well as endophenotypes, mimicking human ADHD. Ghrelin^Δ/Δ zebrafish exhibited downregulated expression levels of wnt1, wnt3a, wnt5a that are critical for dopaminergic neuron development to possibly regulate their number and spatial organization. Pharmacological blockade of wnt signaling with XAV939 induced a reduced moving activity and less dopaminergic neurons; whereas, wnt agonist SB415286 rescued hyperactivity and dopaminergic neuron loss in ghrelin^Δ/Δ zebrafish. In addition, we further identified and validated a SNP, rs696217, on orexigenic hormone preproghrelin/ghrelin (T408T, Met72Met) to be associated with a higher risk of ADHD in a case-controlled association study with 248 subjects with ADHD and 208 subjects of healthy controls. Together, our results reveal a novel endogenous role for orexigenic hormone ghrelin in ADHD, which provides insights into genetic regulation and drug screens for the identification of novel treatments of ADHD.