DRD4 genotyping may differentiate symptoms of attention-deficit/hyperactivity disorder and sluggish cognitive tempo

Differentiating pure cognitive disengagement syndrome and attention-deficit/hyperactivity disorder-restrictive inattentive presentation with respect to depressive symptoms, autistic traits, and neurocognitive profiles

This study aimed to differentiate "pure" cognitive disengagement syndrome (CDS) from attention-deficit/hyperactivity disorder-restrictive inattentive presentation (ADHD-RI) by examining their neurocognitive profiles and associations with autistic traits (ATs) and depressive symptoms. A cross-sectional study was conducted involving three groups: pure CDS (n = 24), ADHD-RI (n = 32), and controls (n = 31). Participants underwent neuropsychological assessments using Computerized Neurocognitive Assessment Software (CNS) Vital Signs, alongside evaluations for ATs with the Autism Spectrum Screening Questionnaire, depressive symptoms with the Children's Depression Inventory, and CDS symptoms with the Barkley Child Attention Scale. A semi-structured interview was also conducted with all participants and their parents to ensure the diagnostic validity of the groups. Findings indicated no dimensional symptomatological distinctions between CDS and ADHD-RI, except for CDS symptoms, and demonstrated no significant differences in neurocognitive test profiles between CDS and ADHD-RI, except for the neurocognition index and reaction time. ATs and depressive symptoms did not significantly differ between the pure CDS and ADHD-RI groups but were significantly elevated in both groups compared to controls. The ADHD-RI group exhibited significantly worse performance than CDS concerning the neurocognition index and reaction time, and worse than controls regarding the neurocognition index, reaction time, psychomotor speed, and complex attention. This study elucidates that ADHD-RI and "pure" CDS have substantially overlapping neurocognitive and phenotypic profiles despite certain minor differences, which is detrimental to subjects with ADHD-RI in terms of overall neurocognition and reaction time. It can be argued that, compared to "pure" CDS, executive dysfunction might be slightly more specific to ADHD-RI, while depressive symptoms and ATs are common in both psychological constructs.

Integration of single-cell sequencing and mendelian randomization reveals novel causal pathways between monocytes and hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) represents one of the most prevalent malignant neoplasms worldwide, characterized by poor prognosis and low 5-year survival rates. Despite extensive research, its pathogenesis remains largely unclear. Within the tumor microenvironment (TME), monocytes play a dual role: they participate in tumor cell recognition and elimination while regulating immune responses through cytokine secretion. This study aims to investigate the association between differentially expressed genes in monocytes and HCC development.

METHODS

This investigation employed single-cell transcriptomic analysis of human hepatic innate lymphoid cells (ILCs) to identify monocyte subpopulations and their cellular markers. Subsequently, two-sample Mendelian randomization (MR) analysis was conducted to examine the causal relationships between these cells, their associated genes, and HCC development.

RESULTS

Through comprehensive analysis of the monocyte cluster, we identified 2338 differentially expressed genes (DEGs). MR analysis revealed 13 genes significantly associated with HCC risk: CONCLUSION: This study represents the first integration of single-cell sequencing technology with MR analysis to investigate the relationship between monocytes and HCC. Through this innovative methodological approach, we have revealed potential associations between monocyte gene expression and HCC development, providing new directions for further research on HCC prevention and treatment, as well as identifying potential therapeutic targets.

The relationship between parental obsessive-compulsive disorder and children's cognitive disengagement syndrome (Sluggish Cognitive Tempo)

Although the impact of parental obsessive-compulsive disorder (OCD) on children is well known, there is a still need to investigate additional psychopathological effects that parental OCD may have on children. To our knowledge, the relationship between Cognitive Disengagement Syndrome (CDS), previously referred to as Sluggish Cognitive Tempo CDS in children and parents' OCD has not been investigated to date. In this study, we examined the relationship between parental OCD and children's CDS, while adjusting for parental anxiety, depression, as well as symptoms of internalization, externalization, and Attention Deficit Hyperactivity Disorder (ADHD) in their children. 50 parents with OCD and 45 healthy parents were assessed through Yale-Brown Obsessive-Compulsive Scale, Beck Depression Inventory, and Beck Anxiety Inventory (BAI). The children were applied Child Behavior Checklist, Children ADD/ADHD DSM-IV Based Diagnostic Screening, and Barkley Child Attention Scale (BCAS). BCAS showed significant correlations with BAI (r = 0.280, p = .049), child ADHD-hyperactivity/impulsivity (r = 0.407, p = .003), and ADHD-inattention (r = 0.628, p < .001). The severity of ADHD-inattention (β = 0.618, p = .001) and parental OCD (β = 0.275, p = .016) were significant predictors of CDS severity in the children. Our findings may suggest a significant association between the severity of CDS and ADHD-inattention in children and parental OCD, even after controlling for parental anxiety.

Adult ADHD: it is old and new at the same time - what is it?

Even though the number of studies aiming to improve comprehension of ADHD pathology has increased in recent years, there still is an urgent need for more effective studies, particularly in understanding adult ADHD, both at preclinical and clinical levels, due to the increasing evidence that adult ADHD is highly distinct and a different entity from childhood ADHD. This review paper outlines the symptoms, diagnostics, and neurobiological mechanisms of ADHD, with emphasis on how adult ADHD could be different from childhood-onset. Data show a difference in the environmental, genetic, epigenetic, and brain structural changes, when combined, could greatly impact the behavioral presentations and the severity of ADHD in adults. Furthermore, a crucial aspect in the quest to fully understand this disorder could be through longitudinal analysis. In this way, we will determine if and how the pathology and pharmacology of ADHD change with age. This goal could revolutionize our understanding of the disorder and address the weaknesses in the current clinical classification systems, improving the characterization and validity of ADHD diagnosis, specifically those in adults.

[Clinical and neurophysiological manifestations of sluggish cognitive tempo in children]

OBJECTIVE

To study the clinical and neurophysiological features of children with low cognitive tempo (NCT), as well as the effectiveness of the drug Pantogam in the treatment of this pathology.

MATERIAL AND METHODS

A total of 90 children aged 8 to 10 years were examined. Of these, the main study group consisted of 30 children with NCT, the comparison group consisted of 30 children with a combined type of attention deficit hyperactivity disorder ADHD (ADHD-K), the control group consisted of 30 children without neuropsychiatric disorders. The study used clinical, neurophysiological (electroencephalography (EEG)) and parametric methods. The CMAS scale of apparent anxiety (The Children's Form of Manifest Anxiety Scale), the SNAP-IY scale (assessment of the degree of inattention, hyperactivity and impulsivity), the TOVA computer test (the Test of Variables of Attention), the scale «SCT» (Sluggish Cognitive Tempo) for assessing manifestations of low cognitive tempo, the «RAM» technique for quantifying working memory. Pantogam was used to treat patients at a dose of 750 mg per day for 8 weeks.

RESULTS

Patients with NCT are characterized by more pronounced attention disorders compared with healthy peers and with children with ADHD-K, and they have a decrease in mainly not selective attention, but the overall level of functional activity. Also, the group of children with NCT has an increased level of anxiety compared to the group of children with ADHD. A comparative analysis of the level of impulsivity showed that children with NCT are less characterized by a deficit in inhibition processes. According to the quantitative analysis of the EEG, specific changes in functional activity in the frontal and central regions of the cerebral cortex were revealed (a statistically significant increase in the ratio of absolute theta rhythm to beta1 rhythm, compared with other groups), reflecting insufficient cortical arousal and less focused neural states. When re-evaluating the condition of children with NCT after a course of therapy with Pantogam, an improvement in the form of a decrease in the degree of inattention, the severity of memory impairment and a decrease in reaction time was recorded in 60% of cases. According to quantitative EEG analysis, there was a significant decrease in the ratio of absolute theta rhythm to beta1 rhythm in the central leads of both hemispheres and in the parietal-temporal leads of the left hemisphere, indicating an increase in the level of overall activation of the cerebral cortex after a course of treatment.

CONCLUSION

Clinical and neurophysiological differences were revealed in patients with NCT and with combined ADHD. It has been shown that the use of Pantogam for the treatment of children with NCT leads not only to a decrease in the main manifestations of this disorder, but also to an improvement in the functional state of the brain.

Comparison of Possible Changes in Oxidative Stress, DNA Damage, and Inflammatory Markers in Children/Adolescents Diagnosed with Sluggish Cognitive Tempo and Children/Adolescents Diagnosed with Attention-Deficit/Hyperactivity Disorder

Background: There has been a debate on whether sluggish cognitive tempo (SCT) differs from attention-deficit/hyperactivity disorder (ADHD). Although there have been many studies on metabolic parameters in relation to ADHD, no similar studies have been conducted on patients with SCT. We investigated whether there are differences between SCT and ADHD in terms of these factors. Subjects and Methods: Sixty-two participants with ages ranging from 11 to 18 who have diagnosis of ADHD (33 subjects) and SCT (29 subjects) were included in this study. The parents of all participants completed the 48-item Conners' Parent Rating Scale (CPRS) and the Barkley Child Attention Scale (BCAS) forms, and all participants' blood was taken to compare metabolic, oxidative stress, and antioxidant status of the SCT and ADHD groups. A child and adolescent psychiatrist interviewed the parents and children to assess the diagnosis of SCT and ADHD using standard diagnostic procedures. Results: In the comparison between the SCT and ADHD groups in terms of metabolic parameters, statistically significant differences were found in terms of total oxidant status, total antioxidant status, Oxidative Stress Index, total thiol, native thiol, disulfide, interleukin (IL)-1β, IL-6, and DNA damage (p < 0.05), but not in terms of tumor necrosis factor-α (p > 0.05). Conclusions: Our data showed that these two disorders may be different, but we believe that the data that indicate their differences remain inconclusive overall, but this study may be a potential pathway for future research.

Report of a Work Group on Sluggish Cognitive Tempo: Key Research Directions and a Consensus Change in Terminology to Cognitive Disengagement Syndrome

OBJECTIVE

The aim of this work was 2-fold: (1) to evaluate current knowledge and identify key directions in the study of sluggish cognitive tempo (SCT); and (2) to arrive at a consensus change in terminology for the construct that reflects the current science and may be more acceptable to researchers, clinicians, caregivers, and patients.

METHOD

An international Work Group was convened that, in early 2021, compiled an online archive of all research studies on SCT and summarized the current state of knowledge, noted methodological issues, and highlighted future directions, and met virtually on 10 occasions in 2021 to discuss these topics and terminology.

RESULTS

Major progress has been made over the last decade in advancing our understanding of SCT across the following domains of inquiry: construct measurement and stability; genetic, environmental, pathophysiologic, and neuropsychological correlates; comorbid conditions; functional impairments; and psychosocial and medication interventions. Findings across these domains are summarized, and potential avenues to pursue in the next generation of SCT-related research are proposed. Following repeated discussions on terminology, the Work Group selected "cognitive disengagement syndrome" (CDS) to replace "SCT" as the name for this construct. This term was deemed to best satisfy considerations that should apply when selecting terms for a condition or syndrome, as it does not overlap with established terms for other constructs, is not offensive, and reflects the current state of the science.

CONCLUSION

It is evident that CDS (SCT) has reached the threshold of recognition as a distinct syndrome. Much work remains to further clarify its nature (eg, transdiagnostic factor, separate disorder, diagnostic specifier), etiologies, demographic factors, relations to other psychopathologies, and linkages to specific domains of functional impairment. Investigators are needed with interests and expertise spanning basic, clinical, and translational research to advance our understanding and to improve the lives of individuals with this unique syndrome.

Investigation of possible associations of the BDNF, SNAP-25 and SYN III genes with the neurocognitive measures: BDNF and SNAP-25 genes might be involved in attention domain, SYN III gene in executive function

OBJECTIVES

Attention-deficit/hyperactivity disorder (ADHD) is a heterogeneous disorder and Sluggish Cognitive Tempo (SCT) might be a second inattention disorder that might be even affected by different attention pathways. SCT is characterized by daydreaming, mental confusion, staring blankly and hypoactivity. In the present study, we evaluated 5 common variants (rs6265, rs3746544, rs1051312, rs133946 and rs133945) located in 3 candidate genes (BDNF, SNAP25 and SYN III) that are known to take part in synaptic plasticity and neurotransmitter transmission.

METHODS

We tested the effects of these variants on neuropsychological findings assessed by a computer-based neuropsychological test battery in children with inattention symptoms (SCT and/or ADHD).

RESULTS

BDNF (rs6265), SNAP25 (rs3746544 and rs1051312) and SYN III (rs133946 and rs133945) polymorphisms were associated with variable cognitive measures. BDNF gene (rs6265) polymorphism Met allele carriers and SNAP25 gene (rs3746544) T allele carriers had an association with the attention domain. SNAP25 gene (rs1051312) C allele carriers were only associated with reaction time scores. Cognitive flexibility, which is one of the key components of executive function evaluation and shifting attention test scores were associated with BDNF (rs6265) Met allele and SYN III (rs133946) gene G allele. SYN III (rs133945) gene C allele carriers had an association with verbal memory correct hit scores.

CONCLUSIONS

As a conclusion, BDNF, SNAP25 and SYN III genes were associated with specific neurocognitive outcomes in children with inattention symptoms. It is important to note that exploring genotyping effects on neurocognitive functions instead of a heterogeneous psychiatric diagnosis can improve our understanding of psychopathologies.

Attention-deficit/hyperactive disorder updates

Background

Attention-deficit/hyperactive disorder (ADHD) is a neurodevelopmental disorder that commonly occurs in children with a prevalence ranging from 3.4 to 7.2%. It profoundly affects academic achievement, well-being, and social interactions. As a result, this disorder is of high cost to both individuals and society. Despite the availability of knowledge regarding the mechanisms of ADHD, the pathogenesis is not clear, hence, the existence of many challenges especially in making correct early diagnosis and provision of accurate management.

Objectives

We aimed to review the pathogenic pathways of ADHD in children. The major focus was to provide an update on the reported etiologies in humans, animal models, modulators, therapies, mechanisms, epigenetic changes, and the interaction between genetic and environmental factors.

Methods

References for this review were identified through a systematic search in PubMed by using special keywords for all years until January 2022.

Results

Several genes have been reported to associate with ADHD: DRD1, DRD2, DRD4, DAT1, TPH2, HTR1A, HTR1B, SLC6A4, HTR2A, DBH, NET1, ADRA2A, ADRA2C, CHRNA4, CHRNA7, GAD1, GRM1, GRM5, GRM7, GRM8, TARBP1, ADGRL3, FGF1, MAOA, BDNF, SNAP25, STX1A, ATXN7, and SORCS2. Some of these genes have evidence both from human beings and animal models, while others have evidence in either humans or animal models only. Notably, most of these animal models are knockout and do not generate the genetic alteration of the patients. Besides, some of the gene polymorphisms reported differ according to the ethnic groups. The majority of the available animal models are related to the dopaminergic pathway. Epigenetic changes including SUMOylation, methylation, and acetylation have been reported in genes related to the dopaminergic pathway.

Conclusion

The dopaminergic pathway remains to be crucial in the pathogenesis of ADHD. It can be affected by environmental factors and other pathways. Nevertheless, it is still unclear how environmental factors relate to all neurotransmitter pathways; thus, more studies are needed. Although several genes have been related to ADHD, there are few animal model studies on the majority of the genes, and they do not generate the genetic alteration of the patients. More animal models and epigenetic studies are required.

ADGRL3, FGF1 and DRD4: Linkage and Association with Working Memory and Perceptual Organization Candidate Endophenotypes in ADHD

Attention deficit hyperactivity disorder (ADHD) is a highly heritable neurobehavioral disorder that affects children worldwide, with detrimental long-term consequences in affected individuals. ADHD-affected patients display visual-motor and visuospatial abilities and skills that depart from those exhibited by non-affected individuals and struggle with perceptual organization, which might partially explain impulsive responses. Endophenotypes (quantifiable or dimensional constructs that are closely related to the root cause of the disease) might provide a more powerful and objective framework for dissecting the underlying neurobiology of ADHD than that of categories offered by the syndromic classification. In here, we explore the potential presence of the linkage and association of single-nucleotide polymorphisms (SNPs), harbored in genes implicated in the etiology of ADHD (ADGRL3, DRD4, and FGF1), with cognitive endophenotypes related to working memory and perceptual organization in 113 nuclear families. These families were ascertained from a geographical area of the Caribbean coast, in the north of Colombia, where the community is characterized by its ethnic diversity and differential gene pool. We found a significant association and linkage of markers ADGRL3-rs1565902, DRD4-rs916457 and FGF1-rs2282794 to neuropsychological tasks outlining working memory and perceptual organization such as performance in the digits forward and backward, arithmetic, similarities, the completion of figures and the assembly of objects. Our results provide strong support to understand ADHD as a combination of working memory and perceptual organization deficits and highlight the importance of the genetic background shaping the neurobiology, clinical complexity, and physiopathology of ADHD. Further, this study supplements new information regarding an ethnically diverse community with a vast African American contribution, where ADHD studies are scarce.

ADHD: Reviewing the Causes and Evaluating Solutions

Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder in which patients present inattention, hyperactivity, and impulsivity. The etiology of this condition is diverse, including environmental factors and the presence of variants of some genes. However, a great diversity exists among patients regarding the presence of these ADHD-associated factors. Moreover, there are variations in the reported neurophysiological correlates of ADHD. ADHD is often treated pharmacologically, producing an improvement in symptomatology, albeit there are patients who are refractory to the main pharmacological treatments or present side effects to these drugs, highlighting the importance of developing other therapeutic options. Different non-pharmacological treatments are in this review addressed, finding diverse results regarding efficacy. Altogether, ADHD is associated with different etiologies, all of them producing changes in brain development, leading to the characteristic symptomatology of this condition. Given the heterogeneous etiology of ADHD, discussion is presented about the convenience of personalizing ADHD treatment, whether pharmacological or non-pharmacological, to reach an optimum effect in the majority of patients. Approaches to personalizing both pharmacological therapy and neurofeedback are presented.