Upper limb function in children with attention-deficit/hyperactivity disorder (ADHD)

Brain iron concentration in childhood ADHD: A systematic review of neuroimaging studies

Iron deficiency may play a role in the pathophysiology of Attention Deficit/Hyperactivity Disorder (ADHD). Due to its preponderant function in monoamine catecholamine and myelin synthesis, brain iron concentration may be of primary interest in the investigation of iron dysregulation in ADHD. This study reviewed current evidence of brain iron abnormalities in children and adolescents with ADHD using magnetic resonance imaging methods, such as relaxometry and quantitative susceptibility mapping, to assess brain iron estimates. The study was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A literature search was performed for studies published between January 1, 2008 and July 7, 2023 in Medline, Scopus and Proquest. Regions of interest, brain iron index values and phenotypical information were extracted from the relevant studies. Risk of bias was assessed using a modified version of the National Heart, Lung, and Blood Institute quality assessment tool. Seven cross-sectional studies comparing brain iron estimates in children with ADHD with neurotypical children were included. Significantly reduced brain iron content in medication-naïve children with ADHD was a consistent finding. Two studies found psychostimulant use may increase and normalize brain iron concentration in children with ADHD. The findings were consistent across the studies despite differing methodologies and may lay the early foundation for the recognition of a potential biomarker in ADHD, although longitudinal prospective neuroimaging studies using larger sample sizes are required. Lastly, the effects of iron supplementation on brain iron concentration in children with ADHD need to be elucidated.

Identifying characteristics and clinical conditions associated with hand grip strength in adults: the Project Baseline Health Study

Low hand grip strength (HGS) is associated with several conditions, but its value outside of the older adult population is unclear. We sought to identify the most salient factors associated with HGS from an extensive list of candidate variables while stratifying by age and sex. We used data from the initial visit from the Project Baseline Health Study (N = 2502) which captured detailed demographic, occupational, social, lifestyle, and clinical data. We applied MI-LASSO using group methods to determine variables most associated with HGS out of 175 candidate variables. We performed analyses separately for sex and age (< 65 vs. ≥ 65 years). Race was associated with HGS to varying degrees across groups. Osteoporosis and osteopenia were negatively associated with HGS in female study participants. Immune cell counts were negatively associated with HGS for male participants ≥ 65 (neutrophils) and female participants (≥ 65, monocytes; < 65, lymphocytes). Most findings were age and/or sex group-specific; few were common across all groups. Several of the variables associated with HGS in each group were novel, while others corroborate previous research. Our results support HGS as a useful indicator of a variety of clinical characteristics; however, its utility varies by age and sex.

Comparison of Fidgeting in Adolescents with Attention-Deficit/Hyperactivity Disorder Between Before and After Stimulant Medication Intake

Objective: Fidgeting is a common symptom in patients with attention-deficit hyperactivity disorder (ADHD). The current study investigated ADHD stimulant medication effects on fidgeting in adolescents with ADHD during a short research study session using wrist-worn accelerometers. Method: Adolescents with ADHD who had been taking stimulant medications (ADHD group) and adolescents without ADHD (control group) participated in the study. Accelerometer data were obtained from both wrists of each participant to track their hand movements during two hearing testing sessions. All subjects in the ADHD group abstained from their stimulant medications for at least 24 hours before their first session (off-med session). The second session (on-med session) was conducted about 60-90 minutes after medication intake. The control group participated in two sessions in a similar time frame. Results: The current study focuses on relationships between hand movements and stimulant medication in adolescents with ADHD. Both conditions were compared to evaluate the relationship of hand movements and stimulant medication. We hypothesized the ADHD group will exhibit less hand movements during the on-medication session in comparison to off-medication session. Conclusion: Wrist-worn accelerometer measures obtained during nonphysical tasks in a short duration may not provide hand movement differences between on-med and off-med conditions in adolescents with ADHD. ClinicalTrials.gov Identifier: NCT04577417.

A Wearable Diagnostic Assessment System vs. SNAP-IV for the auxiliary diagnosis of ADHD: a diagnostic test

OBJECTIVE

We design a diagnostic test to evaluate the effectiveness and accuracy of A non-intrusive Wearable Diagnostic Assessment System versus SNAP-IV for auxiliary diagnosis of children with ADHD.

METHODS

This study included 55 children aged 6-16 years who were clinically diagnosed with ADHD by DSM-5, and 55 healthy children (typically developing). Each subject completes 10 tasks on the WeDA system (Wearable Diagnostic Assessment System) and Parents of each subject complete the SNAP-IV scale. We will calculate the validity indexes, including sensitivity, specificity, Youden's index, likelihood ratio, and other indexes including predictive value, diagnostic odds ratio, diagnostic accuracy and area under the curve [AUC] to assess the effectiveness of the WeDA system as well as the SNAP-IV.

RESULTS

The sensitivity (94.55% vs. 76.36%) and the specificity (98.18% vs. 80.36%) of the WeDA system were significantly higher than the SNAP-IV. The AUC of the WeDA system (0.964) was higher than the SNAP-IV (0.907). There is non-statistically significant difference between groups (p = 0.068), and both of them have high diagnostic accuracy. In addition, the diagnostic efficacy of the WeDA system was higher than that of SNAP-IV in terms of the Youden index, diagnostic accuracy, likelihood ratio, diagnostic odds ratio and predictive value.

CONCLUSION

The advantages of the WeDA system in terms of diagnostic objectivity, scientific design and ease of operation make it a promising system for widespread use in clinical practice.

Handedness in ADHD: Meta-Analyses

Meta-analyses have shown that several neurodevelopmental and psychiatric disorders, such as autism spectrum disorder and schizophrenia, are associated with a higher prevalence of atypical (left-, non-right-, or mixed-) handedness. One neurodevelopmental disorder for which this association is unclear is attention deficit hyperactivity disorder (ADHD). Here, some empirical studies have found evidence for a higher prevalence of atypical handedness in individuals with ADHD compared to neurotypical individuals. However, other studies failed to establish such an association. Therefore, meta-analytic integration is critical to estimate whether or not there is an association between handedness and ADHD. We report the results of three meta-analyses (left-, mixed-, and non-right-handedness) comparing handedness in individuals with ADHD to controls (typically developing individuals). The results show evidence of a trend towards elevated levels of atypical handedness when it comes to differences in left- and mixed-handedness (p = 0.09 and p = 0.07, respectively), but do show clear evidence of elevated levels of non-right-handedness between individuals with ADHD and controls (p = 0.02). These findings are discussed in the context of the hypothesis that ADHD is a disorder in which mostly right-hemispheric brain networks are affected. Since right-handedness represents a dominance of the left motor cortex for fine motor behavior, such as writing, as well as a left-hemispheric dominance for language functions, and about 90% of individuals are right-handers, this hypothesis might explain why there is not stronger evidence for an association of left-handedness with ADHD. We suggest that the mechanisms involved in the pathogenesis of ADHD might show an overlap with the mechanisms involved in handedness strength, but not handedness direction.

Characteristics and Applications of Technology-Aided Hand Functional Assessment: A Systematic Review

Technology-aided hand functional assessment has received considerable attention in recent years. Its applications are required to obtain objective, reliable, and sensitive methods for clinical decision making. This systematic review aims to investigate and discuss characteristics of technology-aided hand functional assessment and their applications, in terms of the adopted sensing technology, evaluation methods and purposes. Based on the shortcomings of current applications, and opportunities offered by emerging systems, this review aims to support the design and the translation to clinical practice of technology-aided hand functional assessment. To this end, a systematic literature search was led, according to recommended PRISMA guidelines, in PubMed and IEEE Xplore databases. The search yielded 208 records, resulting into 23 articles included in the study. Glove-based systems, instrumented objects and body-networked sensor systems appeared from the search, together with vision-based motion capture systems, end-effector, and exoskeleton systems. Inertial measurement unit (IMU) and force sensing resistor (FSR) resulted the sensing technologies most used for kinematic and kinetic analysis. A lack of standardization in system metrics and assessment methods emerged. Future studies that pertinently discuss the pathophysiological content and clinimetrics properties of new systems are required for leading technologies to clinical acceptance.

Inhibitory Control Deficits in Children with Tic Disorders Revealed by Object-Hit-and-Avoid Task

Background

Tic disorders may reflect impaired inhibitory control. This has been evaluated using different behavioural tasks, yielding mixed results. Our objective was to test inhibitory control in children with tics through simultaneous presentation of multiple, mobile stimuli.

Methods

Sixty-four children with tics (mean age 12.4 years; 7.5-18.5) were evaluated using a validated robotic bimanual exoskeleton protocol (Kinarm) in an object-hit-and-avoid task, in which target and distractor objects moved across a screen and participants aimed to hit only the targets while avoiding distractors. Performance was compared to 146 typically developing controls (mean age 13 years; 6.1-19.9). The primary outcome was the percentage of distractors struck.

Results

ANCOVA (age as covariate) showed participants struck significantly more distractors (participants without comorbid ADHD, 22.71% [SE 1.47]; participants with comorbid ADHD, 23.56% [1.47]; and controls, 15.59% [0.68]). Participants with comorbid ADHD struck significantly fewer targets (119.74 [2.77]) than controls, but no difference was found between participants without comorbid ADHD (122.66 [2.77]) and controls (127.00 [1.28]). Participants and controls did not differ significantly in movement speed and movement area. Just over 20% of participants with tics fell below the age-predicted norm in striking distractors, whereas fewer than 10% fell outside age-predicted norms in other task parameters.

Conclusions

In children with tics (without comorbid ADHD), acting upon both targets and distractors suggests reduced ability to suppress responses to potential triggers for action. This may be related to increased sensorimotor noise or abnormal sensory gating.

Oral health status and oral health-related quality of life in children with attention-deficit hyperactivity disorder and oppositional defiant disorder

AIMS

Oral diseases can affect various aspects of life in patients with attention deficit hyperactivity disorder/oppositional defiant disorder (ADHD/ODD). This study aimed to assess the oral health status and oral health-related quality of life (OHRQOL) in ADHD/ODD children.

METHODS

Forty ADHD/ODD and 80 control children aged 3-7 years old were included in the study. Gingival index (GI), dmft score, and the pediatric oral health-related quality of life (POQL) questionnaire were used to determine the oral health status and OHRQOL, respectively.

RESULTS

The mean dmft and GI were significantly higher in the ADHD/ODD group than the control group (P = .002 and P = .001). In the ADHD/ODD children, the total score of OHRQOL and the mean scores of the emotional, physical, role, and social domains were lower than that in the control group (P = .0004, P = .027, P = .002, P = .014, and P = .043, respectively). Poisson's regression showed that there was a significant relationship between OHRQOL and dmft scores (P-value < .001). However, the association between GI and OHRQOL scores was not significant.

CONCLUSION

Higher dmft and GI scores were found in children with ADHD/ODD than the control children. A lower POQL score was detected in ADHD/ODD patients, which translates to a better level of OHRQOL.

Physical Fitness and Dynamic Balance in Medication Naïve Turkish Children with ADHD

This study investigated physical fitness levels and dynamic balance in medication-naïve children with Attention-Deficit/Hyperactivity Disorder (ADHD). Participants were 24 medication-naïve Turkish children with ADHD (4 girls, 20 boys) and 19 typically developing (TD) Turkish children (4 girls, 15 boys). We measured physical fitness levels with the Eurofit Test Battery, body composition with the Inbody 720 Body Composition Analyzer, cognitive attention with the Stroop Test, and dynamic balance with the Y-Balance Test. We found significantly poorer dynamic balance and both upper extremity and running fitness problems among the medication-naïve Turkish children with ADHD compared to the TD group (p = 0.002; p = 0.032; p = 0.002). It may be important to adress dynamic balance and physical fitness when treating children with ADHD.

Using Recurrent Neural Networks to Compare Movement Patterns in ADHD and Normally Developing Children Based on Acceleration Signals from the Wrist and Ankle

Attention deficit and hyperactivity disorder (ADHD) is a neurodevelopmental condition that affects, among other things, the movement patterns of children suffering it. Inattention, hyperactivity and impulsive behaviors, major symptoms characterizing ADHD, result not only in differences in the activity levels but also in the activity patterns themselves. This paper proposes and trains a Recurrent Neural Network (RNN) to characterize the moment patterns for normally developing children and uses the trained RNN in order to assess differences in the movement patterns from children with ADHD. Each child is monitored for 24 consecutive hours, in a normal school day, wearing 4 tri-axial accelerometers (one at each wrist and ankle). The results for both medicated and non-medicated children with ADHD, and for different activity levels are presented. While the movement patterns for non-medicated ADHD diagnosed participants showed higher differences as compared to those of normally developing participants, those differences were only statistically significant for medium intensity movements. On the other hand, the medicated ADHD participants showed statistically different behavior for low intensity movements.

Gender and hand dominance on fine motor skills among Grade 1–7 learners with attention-deficit hyperactivity disorder

Children diagnosed with attention-deficit/hyperactivity disorder encounter difficulties in many activities in their daily lives that require motor coordination skills. The aim of this study was to establish whether children with attention-deficit/hyperactivity disorder have deficits in fine motor skills. Eighty male and female learners diagnosed with attention-deficit/hyperactivity disorder matched with 80 non-attention-deficit/hyperactivity disorder from the North West and Limpopo provinces (South Africa), aged 7–13  years, participated in the study. All participants completed the grooved pegboard test, the maze coordination task, and the finger tapping test. These instruments measure various functions of motor speed and eye–hand coordination. The findings reveal that children with attention-deficit/hyperactivity disorder performed significantly poorer than the control group with regard to the grooved pegboard and maze coordination tasks, but not with the finger tapping task. There were no gender differences in all the tests. Performance on the maze coordination task with the non-dominant hand was poorer for the attention-deficit/hyperactivity disorder group with regard to the time taken to complete the task. However, no hand dominance differences were found on the grooved pegboard and finger tapping tests. The study revealed a relationship between attention-deficit/hyperactivity disorder symptomatology and motor problems with regard to complex tasks of accuracy, but not on a simple task of motor speed. It is, therefore, recommended that since children with attention-deficit/hyperactivity disorder show motor deficiencies, motor skill training should be considered as part of the intervention, as these skills are needed for many daily activities and academic competencies.

Automatic Extraction and Detection of Characteristic Movement Patterns in Children with ADHD Based on a Convolutional Neural Network (CNN) and Acceleration Images

Attention deficit and hyperactivity disorder (ADHD) is a neurodevelopmental disorder, which is characterized by inattention, hyperactivity and impulsive behaviors. In particular, children have difficulty keeping still exhibiting increased fine and gross motor activity. This paper focuses on analyzing the data obtained from two tri-axial accelerometers (one on the wrist of the dominant arm and the other on the ankle of the dominant leg) worn during school hours by a group of 22 children (11 children with ADHD and 11 paired controls). Five of the 11 ADHD diagnosed children were not on medication during the study. The children were not explicitly instructed to perform any particular activity but followed a normal session at school alternating classes of little or moderate physical activity with intermediate breaks of more prominent physical activity. The tri-axial acceleration signals were converted into 2D acceleration images and a Convolutional Neural Network (CNN) was trained to recognize the differences between non-medicated ADHD children and their paired controls. The results show that there were statistically significant differences in the way the two groups moved for the wrist accelerometer (t-test p-value <0.05). For the ankle accelerometer statistical significance was only achieved between data from the non-medicated children in the experimental group and the control group. Using a Convolutional Neural Network (CNN) to automatically extract embedded acceleration patterns and provide an objective measure to help in the diagnosis of ADHD, an accuracy of 0.875 for the wrist sensor and an accuracy of 0.9375 for the ankle sensor was achieved.