ADHD, major depressive disorder, and simple phobias are prevalent psychiatric conditions in youth with velocardiofacial syndrome

Clinical segmentation in 22q11.2 deletion syndrome: Cognitive impairments and additional genetic load

The 22q11.2 deletion syndrome (22q11.2DS) is associated with high psychiatric morbidity. However, large phenotypic heterogeneity hampers early detection of 22q11.2DS individuals at highest risk. Here, we investigated whether individuals with 22q11.2DS can be subdivided into clinically relevant subgroups based on their severity of cognitive impairments and whether such subgroups differ in polygenic risk. Using a cross-sectional design, we examined the number of lifetime psychiatric diagnoses and polygenic risk scores for schizophrenia in an unselected nationwide biobank cohort of individuals with 22q11.2DS (n = 183). Approximately 35% of this sample, aged 10-30 years, had a history with one or more psychiatric diagnosis. In a representative nested subgroup of 28 children and youth, we performed additional comprehensive cognitive evaluation and assessed psychiatric symptoms. Unsupervised hierarchical cluster analysis was performed to divide the subgroup of 22q11.2DS individuals, based on their performance on the cognitive testing battery. This produced two groups that did not differ in mean age or gender composition, but were characterized by low cognitive (LF) and high cognitive (HF) functional levels. The LF group, which had significantly lower global cognitive functioning scores, also displayed higher negative symptom scores; whereas, the HF group displayed lower rate of current psychiatric disorders than the LF group and the reminder of the biobank cohort. The polygenic risk score for schizophrenia was insignificantly lower for the low functioning group than for the high functioning group, after adjustment. Cognitive functioning may provide useful information on psychiatric risk.

Bridging the Communication Gap Between People With Cognitive Impairments and Their Caregivers Using mHealth Apps: User-Centered Design and Evaluation Study With People With 22q11 Deletion Syndrome

BACKGROUND

In families with children with cognitive impairments, both parents and children experience tension and have questions because of a lack of communication and adequate information. Therefore, there is a great need to develop tools that can help bridge the communication gap between patients and caregivers by stimulating conversations and providing psychoeducational tools. mHealth apps show great potential in this context.

OBJECTIVE

The objective of this research is to discover the specific ways young people with cognitive impairments and their families interact with mHealth apps in the context of bridging the communication gap. This newly discovered information leads to potentially more impactful mHealth interventions in the future. Therefore, this paper documents the design and development of a mHealth app for a specific group of people with cognitive impairments-people with 22q11 deletion syndrome (22q11 DS)-and their caregivers, as well as key learnings from the evaluation of this app.

METHODS

An iterative, user-centered design approach is used to design and develop the app. Design and evaluation happens in 2 phases. During the design phase, feedback is gathered from 2 medical experts and 3 human computer interaction (HCI) experts using a low-fidelity paper prototype. During the evaluation phase, feedback is gathered from 8 families with a child with 22q11 DS using a fully working proof of concept. This phase consists of a semistructured interview, a 2-4-week trial period, and a concluding semistructured interview.

RESULTS

The evaluation results of the fully working proof of concept led to design recommendations related to four different topics: (1) overcoming usage barriers, (2) stimulating conversation through a mHealth app, (3) providing information, and (4) bringing continual added value. Results are presented according to six different categories obtained in a thematic analysis: (1) feedback about the app "as is," (2) difficulties, (3) comparison between physical and digital tool, (4) extensions, (5) intention, and (6) other.

CONCLUSIONS

In this research, the need for apps that help bridge the communication gap between a person with cognitive impairment and their caregiver is confirmed. All participating families express their gratitude and mention the added value for other families. Therefore, it is highly encouraged for clinics and institutions to take action and develop an app to be used in practice. Furthermore, considerations when developing for people with 22q11 DS, or more broadly, people with cognitive impairments, are proposed. First, one should keep design principles in mind to overcome usage barriers. Next, recognition is a key concept when stimulating conversations through mobile apps. Third, information should be provided by a trusted source, and more than just clinical information can be considered valuable. Finally, having the possibility of using a digital tool that can be personalized brings continual added value.

Structural Cerebellar Abnormalities and Parkinsonism in Patients with 22q11.2 Deletion Syndrome

Background: The phenotypic expression of 22q11.2 deletion syndrome (22q11.2DS) is variable and may include cognitive, psychiatric, and neurological manifestations, e.g., parkinsonism. We investigated brain structural alterations in patients with 22q11.2DS with and without parkinsonism (Park+ and Park-) in comparison with healthy controls (HCs). Methods: Voxel-based morphometry was performed on 3D T1-weighted MR images to explore gray matter volume (GMV) differences between 29 patients (15 Park+, 14 Park-), selected from a consecutive series of 56 adults diagnosed with 22q11.2DS, and 24 HCs. One-way ANOVA and multiple linear regression analyses were performed to explore group differences in GMV and correlations between clinical scores (MDS-UPDR-III and MoCA scores) and structural alterations. Results: Significant between-group differences in GMV were found in the cerebellum, specifically in bilateral lobes VIII and left Crus II, as well as in the left superior occipital gyrus. Although both Park+ and Park- patients showed GMV decrements in these regions with respect to HCs, GMV loss in the right lobe VIII and left Crus II was greater in Park+ than in Park- patients. GMV loss did not correlate with clinical scores. Conclusions: Patients with 22q11.2DS and parkinsonism manifest specific cerebellar volume alterations, supporting the hypothesis of neurodegenerative processes in specific cerebellar regions as a putative pathophysiological mechanism responsible for parkinsonism in patients with 22q11.2DS.

Psychiatric Comorbidities in Adults with DiGeorge Syndrome

Objective

DiGeorge Syndrome (DGS) is a common multisystem disorder associated with deletions on chromosome 22q11.2. Our objective is to evaluate the psychiatric comorbidities and demographics of patients suffering from DGS in a nationally representative dataset on inpatient hospitalizations.

Methods

The Nationwide Inpatient Sample for the year 2005−2017 was used for this study. Data on patients with DiGeorge syndrome were collected by using the International Classification of Diseases code. Univariate and multivariate logistic regression analysis was performed.

Results

In our study, the average age was 30.4 years (n = 6,563), with 59.9% male, and 61.8% of patients were white. There was a high prevalence of mood disorders (24.7%) and anxiety disorders (16.4%), followed by schizophrenia and other psychotic condition (14.0%). In patients with mood disorders, 8% had Major Depressive Disorder, and 7% had bipolar depression. Overall composite of psychiatric comorbidities was present in 2,959 (45.1%) of patients. The mean length of stay was 6.58 days, and 77% of patients had routine discharge to home. In the adjusted analysis, the average length of stay was 8.6 days vs. 6.7 days (p < 0.001) in patients with and without psychiatry comorbidities. In comparison to routine discharge, patients with psychiatry comorbidities were more likely to be discharged to other healthcare facilities (odds ratio [OR] 1.28, p < 0.001) and discharged against medical advice (OR 3.45, p < 0.001).

Conclusion

Patients with DGS have worse outcomes with a higher rate of discharge to other healthcare facilities and a higher rate of being discharged against medical advice. Further large scale randomize studies are indicated.

Executive function as measured by the Behavior Rating Inventory of Executive Function-2: children and adolescents with Williams syndrome

BACKGROUND

Difficulties with executive functions (EF) are very common among individuals with Williams syndrome (WS). To characterise the pattern of relative strengths and weaknesses in EF for children and adolescents with WS, we considered the performance of a large sample on the parent version of the Behavior Rating Inventory of Executive Function-2 (BRIEF-2). Associations between distinct components of EF and adaptive behaviour, behaviour problems and intellectual ability were investigated. The concurrent effects of components of behaviour regulation and emotion regulation on attention problems and anxiety problems also were evaluated.

METHODS

Participants were 308 6-17-year-olds with genetically confirmed classic WS deletions. Parent report of EF was measured by the BRIEF-2 questionnaire. Most participants (223/308) completed the Differential Ability Scales-II as a measure of intellectual ability. The parents of these individuals also completed the Child Behavior Checklist and the interview form of the Scales of Independent Behavior-Revised.

RESULTS

As a group, the participants evidenced considerable parent-reported EF difficulty. A profile of relative strength and weakness was found at the index level, with performance on both the Behavior Regulation Index and the Emotion Regulation Index significantly better than performance on the Cognitive Regulation Index. Within each index, a statistically significant pattern of relative strength and weakness also was identified. Difficulties with behaviour regulation and emotion regulation were related to both behaviour problems and adaptive behaviour limitations. Higher inflexibility and more difficulty with self-monitoring were associated with lower overall intellectual ability. Difficulty with inhibition was uniquely associated with attention problems, and inflexibility was uniquely associated with anxiety problems.

CONCLUSIONS

Executive function difficulties are highly prevalent among children and adolescents with WS and are associated with adaptive behaviour limitations, both internalising and externalising behaviour problems and more limited intellectual ability. These results highlight the importance of designing and delivering research-based interventions to improve the EF of children and adolescents with WS.

Reflections of parents of children with 22q11.2 Deletion Syndrome on the experience of receiving psychiatric genetic counseling: 'Awareness to Act'

Individuals with 22q11.2 deletion syndrome (22qDS) have a 25%-41% risk for a psychotic disorder. Although early intervention for psychiatric conditions leads to the best long-term outcomes, healthcare providers often provide inadequate information about these issues and psychiatric services are underused by this population. We conducted semi-structured interviews with parents of children with 22qDS a month after they received psychiatric genetic counseling (pGC), to evaluate outcomes and perceived value of pGC with respect to parents' needs. Using grounded theory, we generated a theoretical framework of the process of building parental awareness of psychiatric risks associated with 22qDS and protective and management strategies for mental health (MH). Parents described how after their child's diagnosis with 22qDS, a variety of barriers stalled their building awareness of psychiatric risk and protective/management strategies: dealing with the immediate symptoms of 22qDS; child's young age; parental fear and stigma; and missing MH guidance. These barriers led them to carry the burden of worrying over missing emerging psychiatric symptoms and the stress over advocating for their child's MH. Parents indicated pGC was beneficial in that led them to achieve an 'awareness to act,' feeling confident in being alert and equipped to protect and/or manage their child's MH.

A cross-comparison of cognitive ability across 8 genomic disorders

Genomic disorders result from rearrangement of the human genome. Most genomic disorders are caused by copy number variants (CNV), deletions or duplications of several hundred kilobases. Many CNV loci are associated with autism, schizophrenia, and most commonly, intellectual disability (ID). However, there is little comparison of cognitive ability measures across these CNV disorders. This study aims to understand whether existing data can be leveraged for a cross-comparison of cognitive ability among multiple CNV. We found there is a lack of harmonization among assessment instruments and little standardization for reporting summary data across studies. Despite these limitations, we identified a differential impact of CNV loci on cognitive ability. Our data suggest that future cross-comparisons of CNV disorders will reveal meaningful differences across the phenotypic spectrum, especially if standardized phenotypic assessment is achieved.

Heterozygosity of murine Crkl does not recapitulate behavioral dimensions of human 22q11.2 hemizygosity

Deletions in 22q11.2 human chromosome are known to be associated with psychiatric disorders, such as intellectual disability, schizophrenia, autism spectrum disorder, and anxiety disorders. This copy number variation includes a 3.0 Mb deletion and a nested proximal 1.5 Mb hemizygous deletion in the same region. Evidence indicates that the distal 22q11.2 region outside the nested 1.5 Mb deletion also might be contributory in humans. However, the precise genetic architecture within the distal region responsible for psychiatric disorders remains unclear, and this issue cannot be experimentally evaluated beyond the correlation in humans. As CRKL (CRK-like Proto-Oncogene, Adaptor Protein) is one of the genes encoded in the distal 22q11.2 segment and its homozygous deletion causes physical phenotypes of 22q11.2 hemizygous deletion, we tested the hypothesis that its murine homolog Crkl contributes to behavioral phenotypes relevant to psychiatric disorders in mice. Congenic Crkl heterozygosity reduced thigmotaxis, an anxiety-related behavior, in an inescapable open field, but had no apparent effect on social interaction, spontaneous alternation in a T-maze, anxiety-like behavior in an elevated plus maze, or motor activity in an open field. Our data indicate that the heterozygosity of murine Crkl does not recapitulate social deficits, working memory deficits, repetitive behavior traits or hyperactivity of human 22q11.2 hemizygous deletion. Moreover, while 22q11.2 hemizygous deletion is associated with high levels of phobia and anxiety in humans, our data suggest that Crkl heterozygosity rather acts as a protective factor for phobia-like behavior in an open field.

22q11 microdeletion syndrome and ultra-high risk for psychosis: The role of neurological soft signs as an independent marker of vulnerability for psychosis

AIM

22q11 microdeletion syndrome has an increased risk for psychosis, similar to subjects at ultra-high risk for psychosis. Neurological soft signs are considered an endophenotype of psychotic disorders and a marker of vulnerability to Schizophrenia, consisting of overflow movements, dysrhythmia and speed of timed activities. To date, there are no studies that have evaluated the presence of the neurological soft signs in subjects with 22q11 microdeletion syndrome and there are a few studies that have analysed this issue in subjects at ultra-high risk.

METHODS

We sought to measure neurological soft signs in these two conditions, compared to healthy controls and to analyse the possible correlation between neurological soft signs and positive/negative symptoms both in 22q11 microdeletion syndrome and ultra-high-risk groups. 54 drug-naive patients (29 with 22q11 microdeletion syndrome and 25 at ultra-high risk for psychosis) and 25 healthy controls were evaluated for neurological soft signs.

RESULTS

Both clinical groups showed a greater number of neurological soft signs compared to healthy control, although the two clinical groups did not differ for the number of neurological soft signs. Positive correlation between speed of timed activities and negative symptoms was found in subjects at ultra-high risk.

CONCLUSION

Neurological soft signs could represent a marker of atypical neurodevelopment in the two populations examined. Since we did not found a strong correlation between neurological soft signs and positive/negative symptoms, we suggest that neurological soft signs could be indicators of vulnerability to psychosis independent from the psychopathology.

Myoclonic epilepsy, parkinsonism, schizophrenia and left-handedness as common neuropsychiatric features in 22q11.2 deletion syndrome

BACKGROUND

22q11.2 deletion syndrome (22q11.2DS) is considered as the genetic model of schizophrenia. However, its polymorphic nature has led researchers to further investigate its neuropsychiatric manifestations.

METHODS

We enrolled 56 adults (38 men, 18 women) diagnosed with 22q11.2DS. All subjects were evaluated by a multidisciplinary team. The neuropsychiatric features were investigated by means of clinical and neurophysiological evaluation (video-EEG).

RESULTS

Thirty per cent of our patients were left-handed. Fifty-eight per cent had a low IQ, and 22 of 56 subjects had psychotic disorders (13 of 22 with schizophrenia). Eighteen patients reported at least one seizure in their lifetime, and ten were diagnosed with epilepsy; among them, seven had genetic generalised epilepsy (GGE), and five of seven showed features suggestive of juvenile myoclonic epilepsy (JME). Video-EEG recordings revealed generalised epileptiform abnormalities in 24 of 56 cases. Besides, only one patient with epilepsy had a cardiac malformation. Lastly, 31 of 56 subjects presented with parkinsonism, 16 of whom were taking neuroleptics. None of the 15 patients with parkinsonism not related to neuroleptic therapy was diagnosed with epilepsy, compared with 6 of those taking antipsychotics.

CONCLUSIONS

22q11.2DS is characterised by left-handedness and neuropsychiatric features such as cognitive impairment, schizophrenia, epilepsy and parkinsonism. GGE, mostly the JME phenotype, is the predominant epilepsy type. The significant association between 22q11.2DS and parkinsonian features confirms these patients' genetic susceptibility to parkinsonism. Despite the lack of any conclusive evidence, our study suggests a possible relationship between the analysed clinical variables: (1) an inverse correlation between low IQ/psychosis/epilepsy and major cardiac diseases; (2) a direct association between psychosis and both mental delay and epilepsy; and (3) an inverse correlation between parkinsonism and epilepsy.

Trajectories of psychiatric diagnoses and medication usage in youth with 22q11.2 deletion syndrome: a 9-year longitudinal study

BACKGROUND

Chromosome 22q11.2 deletion syndrome (22q11DS) is associated with high rates of psychiatric disorders, including schizophrenia in up to 30% of individuals with the syndrome. Despite this, we know relatively little about trajectories and predictors of persistence of psychiatric disorders from middle childhood to early adulthood. Accordingly, we followed youth over four timepoints, every 3 years, to assess long-term trajectories of attention-deficit hyperactivity disorder (ADHD), anxiety, mood, and psychosis-spectrum disorders (PSDs), as well as medication usage.

METHODS

Eighty-seven youth with 22q11DS and 65 controls between the ages of 9 and 15 years at the first timepoint (T1; mean age 11.88 ± 2.1) were followed for 9 years (mean age of 21.22 ± 2.01 years at T4). Baseline cognitive, clinical, and familial predictors of persistence were identified for each class of psychiatric disorders.

RESULTS

Baseline age and parent-rated hyperactivity scores predicted ADHD persistence [area under curve (AUC) = 0.81]. The presence of family conflict predicted persistence of anxiety disorders (ADs) whereas parent ratings of child internalizing symptoms predicted persistence of both anxiety and mood disorders (MDs) (AUC = 0.84 and 0.83, respectively). Baseline prodromal symptoms predicted persistent and emergent PSDs (AUC = 0.83). Parent-reported use of anti-depressants/anxiolytics increased significantly from T1 to T4.

CONCLUSIONS

Psychiatric, behavioral, and cognitive functioning during late childhood and early adolescence successfully predicted children with 22q11DS who were at highest risk for persistent psychiatric illness in young adulthood. These findings emphasize the critical importance of early assessments and interventions in youth with 22q11DS.

Intellectual performance profi le of a sample of children and adolescents from Brazil with 22q11.2 Deletion Syndrome (22q11.2DS) based on the Wechsler Scale

Abstract The 22q11.2 Deletion Syndrome (22q11.2DS), the most common human chromosome microdeletion syndrome, is associated with a very heterogeneous neurocognitive phenotype. One of the main characteristics of the syndrome spectrum is the intellectual variability, which encompasses average performance and intellectual disability and discrepancies between Verbal Intelligence Quotient and Performance Verbal Intelligence Quotient, with greater impairment in nonverbal tasks. The present study aimed at investigating the intellectual performance aspects of a 21children and adolescents sample from Brazil who had been diagnosed with 22q11.2DS, based on the Wechsler Intelligence Scale for Children - 4th edition. The samples were reviewed considering the differences between indices. The results revealed an Full Scale Intelligence Quotient predominant in the borderline range (42 to 104) and a significant discrepancy between the indices of Verbal Comprehension and Perceptual Reasoning in 42% of the sample. With regard to the performance in the subtests alone, a better performance was found in Similarities, whereas block design, matrix reasoning, digit span and letter-number sequencing subtests were the most challenging. These findings indicate that a comprehensive assessment of intellectual performance aspects covering the different measures of the Wechsler Intelligence Scale may contribute to a broader understanding of the neurocognitive phenotype associated with 22q11.2DS.

[Child psychiatry interventions in patients with 22q11 deletion syndrome: From treatment to prevention]

22q11.2DS is one of the more frequent genetic syndromes associated to psychiatric symptoms. It has been associated to an increased risk to develop schizophrenia in adolescence or early adulthood. However, psychiatric symptoms appear early on, and should be recognized as soon as possible by child psychiatrists in order to improve the present well-being of children and their family, and to prevent further risks of developing severe and chronic psychiatric diseases later on. In this paper, we present a review of the recent literature concerning the 22q11.2DS syndrome focused on the risk factors that may be associated to an increased risk of psychotic transition. We advocate for the development of systematic specialized child psychiatry consultations for these patients, included in networks with geneticists, adult psychiatrists, and family associations, in order to improve their psychiatric prognosis and to support the development of translational research.

Specific differences in temporal binding aspects of the attentional blink in Chromosome 22q11.2 Deletion Syndrome

Chromosome 22q11.2 Deletion Syndrome (22q11DS) is a genetic syndrome characterized by a variety of cognitive impairments, including difficulty with attention. 22q11DS is the strongest known genetic risk factor for developing schizophrenia, a disorder characterized by impairments in visual attention and temporal binding processes. Here we examine a specific temporal visual attention phenomenon (the attentional blink; AB) within two rapid serial visual presentation tasks, and compare those with 22q11DS to groups of typically developing individuals matched on chronological (CA) and mental age (MA). Performance of individuals with 22q11DS was sensitive to differing task demands. On a Category Task, individuals with 22q11DS performed similarly to control groups on all measures of the AB, with the exception of lower detection accuracy of the first of two targets. In contrast, on a feature-based Color Task which required temporal binding of stimulus features, individuals with 22q11DS differed from CA and MA matched control groups on all AB performance measures, exhibiting lower target accuracy, more temporal binding errors, and a deeper, more protracted AB. Temporal binding in the visual domain is thought to be dependent on a serial attention mechanism that facilitates simultaneous firing of neurons in multiple areas of the visual cortex, activating short-term working memory for storage of bound features. Given the discrepancy between these two tasks, results suggest that temporal binding processes may be significantly affected in individuals with 22q11DS, a finding that importantly, has been previously demonstrated among individuals with schizophrenia.

Neurologic challenges in 22q11.2 deletion syndrome

Children with 22q11.2 deletion syndrome often come to medical attention due to signs and symptoms of neurologic dysfunction. It is imperative to understand the expected neurologic development of patients with this diagnosis in order to be alert for the potential neurologic complications, including cortical malformations, tethered cord, epilepsy, and movement disorders. We present an update of brain imaging findings from the CHOP 22q and You Center, a review of the current literature, and our current management practices for neurological issues.

Understanding the pediatric psychiatric phenotype of 22q11.2 deletion syndrome

The purpose of this article is to provide an overview of current insights into the neurodevelopmental and psychiatric manifestations of 22q11.2 deletion syndrome (22q11DS) in children and adolescents. The pediatric neuropsychiatric expression of 22q11DS is characterized by high variability, both interindividual and intraindividual (different expressions over the lifespan). Besides varying levels of intellectual disability, the prevalence of autism spectrum disorders, attention deficit disorders, anxiety disorders, and psychotic disorders in young individuals with 22q11DS is significantly higher than in the general population, or in individuals with idiopathic intellectual disability. Possible explanations for this observed phenotypic variability will be discussed, including genetic pleiotropy, gene-environment interactions, the age-dependency of phenotypes, but also the impact of assessment and ascertainment bias as well as the limitations of our current diagnostic classification system. The implications inferred by these observations aforementioned bear direct relevance to both scientists and clinicians. Observations regarding the neuropsychiatric manifestations in individuals with 22q11DS exemplify the need for a dimensional approach to neuropsychiatric assessment, in addition to our current categorical diagnostic classification system. The potential usefulness of 22q11DS as a genetic model to study the early phases of schizophrenia as well as the phenomenon of neuropsychiatric pleiotropy observed in many CNV's will be delineated. From a clinical perspective, the importance of regular neuropsychiatric evaluations with attention to symptoms not always captured in diagnostic categories and of maintaining equilibrium between individual difficulties and competencies and environmental demands will be discussed.

Attention Deficit Hyperactivity Disorder Symptoms and Psychosis in 22q11.2 Deletion Syndrome

OBJECTIVE

22q11.2 Deletion Syndrome (22q11.2DS) is associated with increased risk for schizophrenia in adulthood while Attention Deficit Hyperactivity Disorder (ADHD) is the most prevalent diagnosis in childhood. Inattention symptoms are pronounced in 22q11.2DS and given that attentional impairment is a core feature of schizophrenia, inattention symptoms may reflect underlying ADHD, psychosis, or both. We investigate whether inattention is associated with psychosis in 22q11.2DS and in other groups at risk for psychosis but without the deletion (ND) (idiopathic clinical risk and first degree family members of individuals with schizophrenia).

METHODS

One hundred thirty-seven individuals with 22q11.2DS (mean age: 14.0), 84 ND individuals with subthreshold psychosis (mean age: 16.9) and 31 ND individuals with family history of psychosis (mean age: 17.0) were included in the study. Psychopathology was assessed using research diagnostic assessments.

RESULTS

ADHD total symptoms were associated with overall levels of subthreshold psychosis symptoms in 22q11.2DS (β = .8, P = .04). Inattention symptoms were specifically associated with positive (β = .5, P = .004), negative (β = .5, P = .03), and disorganized (β = .5, P < .001) symptoms, while hyperactivity-impulsivity symptoms were associated with disorganized symptoms (β = .5, P = .01). The prevalence of ADHD inattention symptoms was higher in 22q11.2DS with subthreshold psychosis compared to ND individuals with subthreshold psychosis (P < .001), even when adjusting for cognitive impairment and overall psychopathology. The pattern was similar when comparing individuals with 22q11.2DS and ND individuals with family history of psychosis.

CONCLUSIONS

This is the first study to examine the associations between ADHD symptoms and psychosis in 22q11.2DS. Our findings support a potentially important role of ADHD inattention symptoms in psychosis in 22q11.2DS.

Health-related quality of life in 22q11.2 deletion syndrome: The child's perspective

AIM

The 22q11.2 deletion syndrome (22qDS) is a genetic syndrome that results in a complex physical, behavioural and psychological phenotype. Health-related quality of life (HRQOL) is an established clinical outcome that has been minimally studied in children with 22qDS. The purpose of this study was to explore HRQOL among children and adolescents with 22qDS from the perspective of the child and to determine how their HRQOL measures compare to those of a healthy peer group and a chronic disease peer group.

METHODS

We recruited individuals between the ages of 8 and 18 with a positive genetic diagnosis of 22qDS (n = 28) and a parent of the child. Participants completed the paired Paediatric Quality of Life Inventory 4.0 questionnaires. Comparisons were made with a previous study of healthy and diseased children.

RESULTS

Children with 22qDS had a significantly poorer HRQOL when compared to age-matched cohorts of healthy children and children with chronic disease. Within the study, there was variable proxy-self agreement, and children with 22qDS reported lower HRQOL than adolescents with 22qDS.

CONCLUSION

This study is the first to explore HRQOL from the perspective of the child with 22qDS, and our findings support the existing literature that this condition is associated with a poor HRQOL.

Frontal dysconnectivity in 22q11.2 deletion syndrome: an atlas-based functional connectivity analysis

BACKGROUND

22q11.2 deletion syndrome (22q11DS) is a neurodevelopmental syndrome associated with deficits in cognitive and emotional processing. This syndrome represents one of the highest risk factors for the development of schizophrenia. Previous studies of functional connectivity (FC) in 22q11DS report aberrant connectivity patterns in large-scale networks that are associated with the development of psychotic symptoms.

METHODS

In this study, we performed a functional connectivity analysis using the CONN toolbox to test for differential connectivity patterns between 54 individuals with 22q11DS and 30 healthy controls, between the ages of 17-25 years old. We mapped resting-state fMRI data onto 68 atlas-based regions of interest (ROIs) generated by the Desikan-Killany atlas in FreeSurfer, resulting in 2278 ROI-to-ROI connections for which we determined total linear temporal associations between each. Within the group with 22q11DS only, we further tested the association between prodromal symptoms of psychosis and FC.

RESULTS

We observed that relative to controls, individuals with 22q11DS displayed increased FC in lobar networks involving the frontal-frontal, frontal-parietal, and frontal-occipital ROIs. In contrast, FC between ROIs in the parietal-temporal and occipital lobes was reduced in the 22q11DS group relative to healthy controls. Moreover, positive psychotic symptoms were positively associated with increased functional connections between the left precuneus and right superior frontal gyrus, as well as reduced functional connectivity between the bilateral pericalcarine. Positive symptoms were negatively associated with increased functional connectivity between the right pericalcarine and right postcentral gyrus.

CONCLUSIONS

Our results suggest that functional organization may be altered in 22q11DS, leading to disruption in connectivity between frontal and other lobar substructures, and potentially increasing risk for prodromal psychosis.

LINE-1 retrotransposons in healthy and diseased human brain

Long interspersed element-1 (LINE-1 or L1) is a transposable element with the ability to self-mobilize throughout the human genome. The L1 elements found in the human brain is hypothesized to date back 56 million years ago and has survived evolution, currently accounting for 17% of the human genome. L1 retrotransposition has been theorized to contribute to somatic mosaicism. This review focuses on the presence of L1 in the healthy and diseased human brain, such as in autism spectrum disorders. Throughout this exploration, we will discuss the impact L1 has on neurological disorders that can occur throughout the human lifetime. With this, we hope to better understand the complex role of L1 in the human brain development and its implications to human cognition. © 2017 Wiley Periodicals, Inc. Develop Neurobiol 78: 434-455, 2018.

Does differential visual exploration contribute to visual memory impairments in 22q11.2 microdeletion syndrome?

BACKGROUND

Chromosome 22q11.2 microdeletion syndrome (22q11.2DS) is a genetic syndrome characterised by a unique cognitive profile. Individuals with the syndrome present several non-verbal deficits, including visual memory impairments and atypical exploration of visual information. In this study, we seek to understand how visual attention may contribute to memory difficulties in 22q11.2DS by tracking eye movements during the encoding phase of a visual short-term memory task.

METHOD

Eye movements were recorded during a computerised version of the multiple-choice Benton Visual Retention Test, which consisted of exploring and then recognising complex visual stimuli. Seventy-four participants affected by 22q11.2DS were compared with 70 typically developing participants.

RESULTS

Participants with 22q11.2DS performed less well than healthy controls on the task and spent more time and fixations on the principal (larger central) figures and less time and fixations on the smaller peripheral figures within the stimuli.

CONCLUSIONS

This study is the first to investigate visual attention in 22q11.2DS during a memory task. The results delineate impaired processes during encoding that affect visual memory performance. The findings may be especially useful for informing interventions intended to boost visual learning in patients with 22q11.2DS.

Negative subthreshold psychotic symptoms distinguish 22q11.2 deletion syndrome from other neurodevelopmental disorders: A two-site study

About one third of individuals with 22q11.2 deletion syndrome (22q11.2DS) develop schizophrenia. Notably, a full-blown psychotic disorder is usually preceded by subthreshold symptoms. Therefore, it is important to identify early signs of psychosis in this population, a task that is complicated by the intellectual disabilities typically seen in 22q11.2DS. We aimed to identify subthreshold psychotic symptoms that distinguish 22q11.2DS from other neurodevelopmental disorders. The study included two independent cohorts from Tel Aviv and Philadelphia. 22q11.2DS (N=171) and typically developing (TD; N=832) individuals were enrolled at both sites and further compared to two groups with intellectual disabilities: Williams syndrome (WS; N=21) in the Tel Aviv cohort and idiopathic developmental disabilities (IDD; N=129) in the Philadelphia cohort. Participants and their primary caregivers were interviewed with the Structured Interview for Prodromal Symptoms (SIPS) and psychopathologies were assessed using standardized tools; general cognitive abilities were assessed with the Computerized Neurocognitive Battery. Negative/disorganized subthreshold syndrome was significantly more common in the 22q11.2DS group than in the WS (OR=3.90, 95% CI=1.34-11.34) or IDD (OR=5.05, 95% CI=3.01-10.08) groups. The 22q11.2DS group had higher scores than the two intellectual disabilities groups on several SIPS negative items, including avolition and decreased expression of emotion. Overall, there were few significant correlations between level of cognitive deficits and severity of negative symptoms in 22q11.2DS and only in the Tel Aviv cohort. Our findings suggest that 22q11.2DS individuals at the age of risk for developing psychosis should be closely monitored for negative symptoms.

Prevalence and treatment of psychiatric disorders other than psychosis in children and adolescents with 22q11DS: Examining associations with social and role functioning

Individuals with chromosome 22q11 deletion syndrome (22q11DS) have high rates of psychotic disorders. Less is known about their psychopathology and how it is treated prior to the peak period of risk for psychotic disorder. There is also a lack of evidence on how functioning is impacted by psychopathology in this population. The aim of this study was to investigate the prevalence and treatment of non-psychotic psychiatric disorders, and how these factors are associated with psychosocial functioning in children and adolescents with 22q11DS. 126 individuals with 22q11DS aged 8-17 participated in the study. Participants were assessed for psychiatric diagnoses, social and role functioning, anxiety and depressive symptoms and IQ. Information on current treatments was collected. 52.4% of the sample presented with at least one psychiatric disorder. Mood and anxiety disorders were the most frequent, followed by behavioural disorder. Individuals with a psychiatric disorder had significantly lower general, role and social functioning. Only 27% of participants with a psychiatric diagnosis were receiving any mental health treatment at the time of assessment. Findings suggest the high prevalence of psychiatric disorders in youth with 22q11DS, which significantly impacts psychosocial functioning. Despite this, psychiatric disorders tend to remain untreated in this population.

Childhood predictors of written expression in late adolescents with 22q11.2 deletion syndrome: a longitudinal study

BACKGROUND

22q11.2 deletion syndrome (22q11DS) is the second most prevalent genetic syndrome and has a characteristic academic and behavioural phenotype. The primary objective of the current study was to examine the childhood predictors of written expression achievement in adolescents with 22q11DS. Written expression is an important skill that can impact an individual's overall academic performance, potentially resulting in increased levels of stress and exacerbation of psychiatric symptoms.

METHODS

A total of 119 participants were included in this study. Sixty-nine late adolescents with 22q11DS and 50 controls (consisting of a combined sample of 23 unaffected siblings of youth with 22q11DS and 27 community controls) participated in a 6-year longitudinal research project and received neuropsychological test batteries every 3 years. The Written Expression subtest of the Wechsler Individual Achievement Test - Second Edition was the primary outcome measure in the current project.

RESULTS

Findings indicated differences in childhood predictors of adolescent written expression between participants in the 22q11DS group and participants in the control group. Whereas childhood verbal IQ scores predicted adolescent written expression for participants in the control group, childhood executive function and language skills were unique predictors of adolescent written expression in individuals with 22q11DS.

CONCLUSIONS

Childhood predictors of late adolescent written expression in 22q11DS differ in meaningful ways from predictors in the non-22q11DS population. These results offer some guidance on the underlying factors that may be useful to consider when developing written expression interventions for children with 22q11DS.

Examining a New Method to Studying Velopharyngeal Structures in a Child With 22q11.2 Deletion Syndrome

PURPOSE

To date, no studies have imaged the velopharynx in children with 22q11.2 deletion syndrome (22q11.2 DS) without the use of sedation. Dysmorphology in velopharyngeal structures has been shown to have significant negative implications on speech among these individuals. This single case study was designed to assess the feasibility of a child-friendly magnetic resonance imaging (MRI) scanning protocol in this clinically challenging population and to determine the utility of this MRI protocol for future work in this area.

METHOD

One 6-year-old White girl diagnosed with 22q11.2 DS was imaged using a child-friendly, nonsedated MRI protocol. Quantitative and qualitative measures of the velopharyngeal area and associated structures were evaluated, and comparisons were made to age-matched control subjects with normal velopharyngeal anatomy.

RESULTS

MRI data were successfully obtained using the child-friendly scanning protocol in the subject in the present study. Quantitative and qualitative differences of the levator muscle and associated velopharyngeal structures were noted. Using these MRI and structural analyses methods, insights related to muscle morphology can be obtained and considered as part of the research and clinical examination of children with 22q11.2 DS.

CONCLUSION

The imaging protocol described in this study presents an effective means to counteract difficulties in imaging young children.

Longitudinal study of cerebral surface morphology in youth with 22q11.2 deletion syndrome, and association with positive symptoms of psychosis

BACKGROUND

22q11.2 deletion syndrome (22q11DS) is a genetic disorder that greatly increases risk of developing schizophrenia. We previously characterized cerebral surface morphology trajectories from late childhood to mid adolescence in a cohort of youth with 22q11DS. Herein, we extend the study period into early adulthood, and describe further the trajectories associated with severe psychiatric symptoms in this cohort.

METHODS

Participants included 76 youth with 22q11DS and 30 unaffected siblings, assessed at three timepoints, during which high resolution, anatomic magnetic resonance images were acquired. High-dimensional, nonlinear warping algorithms were applied to images in order to derive characteristics of cerebral surface morphology for each participant at each timepoint. Repeated-measures, linear regressions using a mixed model were conducted, while covarying for age and sex.

RESULTS

Alterations in cerebral surface morphology during late adolescence/early adulthood in individuals with 22q11DS were observed in the lateral frontal, orbitofrontal, temporal, parietal, occipital, and cerebellar regions. An Age x Diagnosis interaction revealed that relative to unaffected siblings, individuals with 22q11DS showed age-related surface protrusions in the prefrontal cortex (which remained stable or increased during early adulthood), and surface indentations in posterior regions (which seemed to level off during late adolescence). Symptoms of psychosis were associated with a trajectory of surface indentations in the orbitofrontal and parietal regions.

CONCLUSIONS

These results advance our understanding of cerebral maturation in individuals with 22q11DS, and provide clinically relevant information about the psychiatric phenotype associated with the longitudinal trajectory of cortical surface morphology in youth with this genetic syndrome.

The social brain network in 22q11.2 deletion syndrome: a diffusion tensor imaging study

BACKGROUND

Chromosome 22q11.2 deletion syndrome (22q11.2DS) is a neurogenetic disorder that is associated with a 25-fold increase in schizophrenia. Both individuals with 22q11.2DS and those with schizophrenia present with social cognitive deficits, which are putatively subserved by a network of brain regions that are involved in the processing of social cognitive information. This study used two-tensor tractography to examine the white matter tracts believed to underlie the social brain network in a group of 57 young adults with 22q11.2DS compared to 30 unaffected controls.

RESULTS

Results indicated that relative to controls, participants with 22q11.2DS showed significant differences in several DTI metrics within the inferior fronto-occipital fasciculus, cingulum bundle, thalamo-frontal tract, and inferior longitudinal fasciculus. In addition, participants with 22q11.2DS showed significant differences in scores on measures of social cognition, including the Social Responsiveness Scale and Trait Emotional Intelligence Questionnaire. Further analyses among individuals with 22q11.2DS demonstrated an association between DTI metrics and positive and negative symptoms of psychosis, as well as differentiation between individuals with 22q11.2DS and overt psychosis, relative to those with positive prodromal symptoms or no psychosis.

CONCLUSIONS

Findings suggest that white matter disruption, specifically disrupted axonal coherence in the right inferior fronto-occipital fasciculus, may be a biomarker for social cognitive difficulties and psychosis in individuals with 22q11.2DS.

Associations between social cognition, skills, and function and subclinical negative and positive symptoms in 22q11.2 deletion syndrome

Background

Identification of the early signs of schizophrenia would be a major achievement for the early intervention and prevention strategies in psychiatry. Social impairments are defining features of schizophrenia. Impairments of individual layers of social competencies are frequently described in individuals with 22q11.2 deletion syndrome (22q11.2DS), who have high risk of schizophrenia. It is unclear whether and to what extent social impairments associate with subclinical negative and positive symptoms in 22q11.2DS, and which layer of social impairments are more correlated with schizophrenia-related symptoms. The aims of this study were to conduct a comprehensive investigation of social impairments at three different levels (function, skill, and cognition) and their interrelationship and to determine to what degree the social impairments correlate to subclinical levels of negative and positive symptoms, respectively, in a young cohort of 22q11.2DS not diagnosed with schizophrenia.

Methods

The level of social impairment was addressed using questionnaires and objective measures of social functioning (The Adaptive Behavior Assessment System), skills (Social Responsiveness Scale), and cognition (The Awareness of Social Inference Test and CANTAB Emotional Recognition Task), and the presence of subclinical symptoms of schizophrenia were evaluated using the Structured Interview for Prodromal Syndromes in a cross-sectional case-control study of 29 cases and 29 controls, aged 12 to 25 years. Association between social impairment and negative and positive symptoms levels was examined in cases only.

Results

Subjects with 22q11.2DS were highly impaired in social function, social skills, and social cognition (p ≤ 6.2 × 10⁻⁹) relative to control peers and presented with more negative (p = 5.8 × 10⁻¹¹) and positive (p = 7.5 × 10⁻⁴) symptoms. In particular, social functional and skill levels were highly associated with notably subclinical negative symptoms levels.

Conclusions

This study shows strong correlations between levels of social impairments and subclinical negative and positive symptoms. However, longitudinal studies are required to show if social impairments represent early disease manifestations. If parental or self-reporting suggests severe social impairment, it should advocate for clinical awareness not only to social deficits per se but also of potential subclinical psychosis symptoms.

[Formula: see text]Executive functioning and its relation to ASD and ADHD symptomatology in 22q11.2 deletion syndrome

Children with 22q11.2 deletion syndrome (22q11DS; velo-cardio-facial-syndrome) are at risk for the developmental disorders, attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD). In this study, the relation between executive functioning (EF) and the severity of ADHD and ASD symptoms is examined, since EF is known to be important in relation to emotional and behavioral problems. The participants consist of 58 children (38 females) with a mean age of 13.5 years (SD 2.6). Standardized assessment was used to evaluate the severity of ASD and ADHD symptomatology. The major aspects of EF, i.e., cognitive flexibility, inhibition, sustained attention, distractibility, working memory and reaction speed, were evaluated. The profile of EF in 22q11DS was found to be characterized by weaker performance compared to the norms on all subdomains of EF. Poor cognitive flexibility and inhibition, as well as high distractibility, were found to be related to more severe ASD symptoms, while poor quality of sustained attention and high distractibility were found to be related to more severe ADHD symptoms. It is concluded that children with 22q11DS experience impairments in EF, and that the degree of impairment on specific EF subdomains is related to the severity of ASD and/or ADHD symptomatology. These results may help in defining the mediating role of neurocognitive dysfunctions in the development of social and behavioral problems in 22q11DS.

Cognitive phenotype and psychiatric disorder in 22q11.2 deletion syndrome: A review

The behavioural phenotype of 22q11.2 deletion syndrome syndrome (22q11DS), one of the most common human multiple anomaly syndromes, frequently includes intellectual disability (ID) together with high risk of diagnosis of psychotic disorders including schizophrenia. Candidate cognitive endophenotypes include problems with retrieval of contextual information from memory and in executive control and focussing of attention. 22q11DS may offer a model of the relationship between ID and risk of psychiatric disorder. This paper reviews research on the relationship between the cognitive phenotype and the development of psychiatric disorders in 22q11DS. Aspects of cognitive function including verbal I.Q., visual memory, and executive function, are associated with mental health outcome in people with 22q11DS. This relationship may result from a common neurobiological basis for the cognitive difficulties and psychiatric disorders. Some of the cognitive difficulties experienced by people with 22q11DS, especially in attention, memory retrieval, and face processing, may, however, in themselves constitute risk factors for development of hallucinations and paranoid delusions. Future research into factors leading to psychiatric disorder in people with 22q11DS should include assessment of social and psychological factors including life events, symptoms associated with trauma, attachment, and self-esteem, which together with cognitive risk factors may mediate mental health outcome.

Facial emotion perception by intensity in children and adolescents with 22q11.2 deletion syndrome

Difficulties in the recognition of emotions in expressive faces have been reported in people with 22q11.2 deletion syndrome (22q11.2DS). However, while low-intensity expressive faces are frequent in everyday life, nothing is known about their ability to perceive facial emotions depending on the intensity of expression. Through a visual matching task, children and adolescents with 22q11.2DS as well as gender- and age-matched healthy participants were asked to categorise the emotion of a target face among six possible expressions. Static pictures of morphs between neutrality and expressions were used to parametrically manipulate the intensity of the target face. In comparison to healthy controls, results showed higher perception thresholds (i.e. a more intense expression is needed to perceive the emotion) and lower accuracy for the most expressive faces indicating reduced categorisation abilities in the 22q11.2DS group. The number of intrusions (i.e. each time an emotion is perceived as another one) and a more gradual perception performance indicated smooth boundaries between emotional categories. Correlational analyses with neuropsychological and clinical measures suggested that reduced visual skills may be associated with impaired categorisation of facial emotions. Overall, the present study indicates greater difficulties for children and adolescents with 22q11.2DS to perceive an emotion in low-intensity expressive faces. This disability is subtended by emotional categories that are not sharply organised. It also suggests that these difficulties may be associated with impaired visual cognition, a hallmark of the cognitive deficits observed in the syndrome. These data yield promising tracks for future experimental and clinical investigations.

Longitudinal study of premorbid adjustment in 22q11.2 deletion (velocardiofacial) syndrome and association with psychosis

Velocardiofacial syndrome, also known as 22q11.2 deletion syndrome (22q11DS), is associated with an increased risk of major psychiatric disorders, including schizophrenia. The emergence of psychotic symptoms in individuals with schizophrenia in the general population is often preceded by a premorbid period of poor or worsening social and/or academic functioning. Our current study evaluated premorbid adjustment (via the Cannon-Spoor Premorbid Adjustment Scale [PAS]) and psychotic symptoms (via the Structured Interview for Prodromal Symptoms and the Kiddie Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime Version) in youth with 22q11DS (N = 96), unaffected siblings (N = 40), and community controls (N = 50). The PAS scores indicated greater maladjustment during all developmental periods in individuals with 22q11DS compared to the controls. Many participants with 22q11DS had chronically poor (n = 33) or deteriorating (n = 6) PAS scores. In 22q11DS, chronically poor PAS trajectories and poor childhood and early adolescence academic domain and total PAS scores significantly increased the risk of prodromal symptoms or overt psychosis. Taking into account the catechol-O-methyltransferase (COMT) genotype, the best predictor of (prodromal) psychosis was the early adolescence academic domain score, which yielded higher sensitivity and specificity in the subgroup of youth with 22q11DS and the high-activity (valine) allele. PAS scores may help identify individuals at higher risk for psychosis.

Atypical functional connectivity in resting-state networks of individuals with 22q11.2 deletion syndrome: associations with neurocognitive and psychiatric functioning

BACKGROUND

22q11.2 deletion syndrome (22q11DS) is a neurogenetic condition associated with deficits in neuropsychological functioning and psychiatric disorders. This deletion confers a high risk for the development of psychosis, as approximately 30-45 % of individuals develop psychosis in adulthood. Previous reports of resting-state functional magnetic resonance imaging (rs-fMRI) functional connectivity patterns in 22q11DS have demonstrated that atypical connectivity is associated with both the emergence and severity of psychotic symptoms. However, due to sample overlap and large age ranges of samples spanning multiple critical periods of brain maturation, more independent studies with samples within the window of time when psychotic symptoms have been shown to emerge (ages 17-26) are needed. Resting-state networks (RSNs) in 22q11DS during this stage of brain development may thus provide insight into the dynamic changes in functional integration that influence the incidence of prodromal symptoms and neurocognitive deficits characteristic of this syndrome.

METHODS

Independent component analysis (ICA) was performed to identify RSNs in a combined sample of 55 individuals with 22q11DS (27 males; age range 17-26) and 29 controls (17 males; age range 17-23, consisting of 8 siblings without the deletion and 21 typically developed individuals) from two research sites. We conducted a full factorial analysis to determine group differences between 22q11DS and controls. A Poisson regression analysis was conducted in the 22q11DS group to determine relationships of rs-fMRI network connectivity with psychiatric symptoms based on factors of the 18-item Brief Psychiatric Rating Scale. Nonparametric Spearman correlations were performed to test associations between within-network functional connectivity (FC) and performance on measures of verbal memory (California Verbal Learning Test) and executive function (Behavior Rating Inventory of Executive Function Adult version) in 22q11DS.

RESULTS

Between-group network connectivity analyses revealed significant differences in 9 RSNs. Decreased network FC in 22q11DS was observed in the following networks: high-level visual processing network (HLVPN), low-level visual processing network (LLVPN), visual/precuneus network, left frontal-parietal network (LFPN), right frontal-parietal network (RFPN), and self-referential network (SRN). In contrast, greater network FC in 22q11DS was observed in subclusters of the LLVPN, visual/precuneus network, limbic network (LN), default mode network (DMN), and visuospatial processing network (VSPN). Increased functional connectivity of the right cuneus (visual/precuneus network) and right superior parietal lobule (DMN) in 22q11DS was positively associated with both thought disturbance and disorganization factors of the Brief Psychiatric Rating Scale (BPRS). Decreased functional connectivity in the left posterior cingulate (LLVPN) was associated with higher thought disturbance scores in 22q11DS. No associations with our neurocognitive measures passed correction for multiple comparisons (Bonferroni-corrected p ≤ 0.0014).

CONCLUSIONS

Our findings suggest that atypical network connectivity within RSNs may be indicative of increased risk for developing psychosis and supports the utility of RSNs as biomarkers of prodromal symptoms in 22q11DS.

Alagille Syndrome: A Case Report Highlighting Dysmorphic Facies, Chronic Illness, and Depression

Alagille syndrome is a rare multisystem disorder affecting the liver, heart, vertebrae, eyes, and face. Alagille syndrome shares multiple phenotypic variants of other congenital or chronic childhood illnesses such as DiGeorge syndrome, Down syndrome, spina bifida, type 1 diabetes mellitus, and cystic fibrosis. All of these chronic illnesses have well-established links to psychiatric conditions. There are few community resources for Alagille patients, as it is an extremely rare condition. Despite the overlap with other chronic childhood illnesses, the psychiatric manifestations of Alagille syndrome have not been previously discussed in literature. The current study is a case report of a twelve-year-old female hospitalized in our pediatric psychiatric hospital for suicidal ideation with intent and plan. The patient had major depressive disorder, anxiety, other specified feeding and eating disorder, and attention-deficit/hyperactive disorder.

Altered Brain Structure-Function Relationships Underlie Executive Dysfunction in 22q11.2 Deletion Syndrome

22q11.2 deletion syndrome (22q11DS) is a neurogenetic disorder associated with elevated rates of developmental neuropsychiatric disorders and impaired executive function (EF). Disrupted brain structure-function relationships may underlie EF deficits in 22q11DS. We administered the Behavior Rating Inventory of Executive Function (BRIEF) to assess real-world EF in patients with 22q11DS and matched controls (n = 86; age 6-17 years), along with cognitive measures that tap behavioral regulation and metacognition aspects of EF. Using FreeSurfer's whole-brain vertex cortical thickness pipeline, we investigated brain structure-EF relationships in patients with 22q11DS and controls. Behaviorally, patients with 22q11DS were impaired on multiple EF measures. Right orbitofrontal cortical thickness showed a differential relationship between real-world EF in patients with 22q11DS and controls. We also observed a group difference in the relationship between behavioral regulation and metacognition measures with thickness of ventral and dorsolateral prefrontal regions, respectively. Our findings suggest that executive dysfunction characteristic of 22q11DS is underscored by altered prefrontal cortical structure.

Behavioral and Psychiatric Phenotypes in 22q11.2 Deletion Syndrome

22q11.2 Deletion syndrome (22q11.2DS) is a chromosomal microdeletion that affects approximately 40 to 50 genes and affects various organs and systems throughout the body. Detection is typically achieved by fluorescence in situ hybridization after diagnosis of one of the major features of the deletion or via chromosomal microarray or noninvasive prenatal testing. The physical phenotype can include congenital heart defects, palatal and pharyngeal anomalies, hypocalcemia/hypoparathyroidism, skeletal abnormalities, and cranial/brain anomalies, although prevalence rates of all these features are variable. Cognitive function is impaired to some degree in most individuals, with prevalence rates of greater than 90% for motor/speech delays and learning disabilities. Attention, executive function, working memory, visual-spatial abilities, motor skills, and social cognition/social skills are affected. The deletion is also associated with an increased risk for behavioral disorders and psychiatric illness. The early onset of psychiatric symptoms common to 22q11.2DS disrupts the development and quality of life of individuals with the syndrome and is also a potential risk factor for later development of a psychotic disorder. This review discusses prevalence, phenotypic features, and management of psychiatric disorders commonly diagnosed in children and adolescents with 22q11.2DS, including autism spectrum disorders, attention deficit/hyperactivity disorder, anxiety disorders, mood disorders, and schizophrenia/psychotic disorders. Guidelines for the clinical assessment and management of psychiatric disorders in youth with this syndrome are provided, as are treatment guidelines for the use of psychiatric medications.

PRODH rs450046 and proline x COMT Val¹⁵⁸ Met interaction effects on intelligence and startle in adults with 22q11 deletion syndrome

RATIONALE

22q11 deletion syndrome (22q11DS) is associated with an increased risk for psychotic disorders, suggesting a relationship between genotypes and the pathophysiology of psychotic disorders. Two genes in the deleted region, catechol-O-methyl-transferase (COMT) and proline dehydrogenase (oxidase) 1 (PRODH), contain polymorphisms associated with neuropsychiatric phenotypes.

OBJECTIVES

Here, we explored the association between polymorphisms and full-scale intelligence (FSIQ), startle reactivity (SR) and prepulse inhibition (PPI) in adults with 22q11DS.

METHODS

Forty-five adults with 22q11DS were genotyped for PRODH rs450046, rs372055 and COMT Val(158)Met. Plasma proline levels, FSIQ, SR and PPI were measured.

RESULTS

Thirty-five percent of the subjects were hyperprolinemic with a median proline value of 456 μmol/L. C allele carriers of PRODH rs450046 had a lower FSIQ compared to T allele carriers, indicating the C allele to be a risk allele (C allele: mean FSIQ 60.2 (sd 8.7); T allele: mean FSIQ 73.7 (sd 11.5); F 1,43 = 7.59; p = 0.009; partial η (2) = 0.15). A significant interaction effect of proline levels and COMT Val(158)Met genotype was found for SR (F 1,16 = 7.9; p = 0.01; partial η (2) = 0.33), but not for PPI and FSIQ. In subjects with hyperprolinemia, the COMT Val(158)Met genotype effect on SR was stronger than in subjects with normal proline levels.

CONCLUSIONS

Overall, these data provide further evidence for the risk effect of elevated proline levels combined with the COMT Met allele and support the possibilities of using 22q11DS as a model to investigate genotype effects on psychiatric disorders.

Neurocognitive and familial moderators of psychiatric risk in velocardiofacial (22q11.2 deletion) syndrome: a longitudinal study

BACKGROUND

Although risk for psychosis in velocardiofacial (22q11.2 deletion) syndrome (VCFS) is well established, the cognitive and familial factors that moderate that risk are poorly understood.

METHOD

A total of 75 youth with VCFS were assessed at three time points, at 3-year intervals. Time 1 (T1) psychiatric risk was assessed with the Behavior Assessment System for Children (BASC). Data reduction of BASC scores yielded avoidance-anxiety and dysregulation factors. Time 2 (T2) neuropsychological and family function and time 3 (T3) prodromal/overt psychosis were assessed. Poisson regression models tested associations between T3 positive prodromal symptoms/overt psychosis and T1 psychiatric risk, T2 cognitive and familial factors, and their interactions.

RESULTS

T1 avoidance-anxiety ratings predicted T3 prodromal/overt psychosis. T2 verbal learning scores moderated this association, such that individuals with low avoidance-anxiety scores and stronger verbal learning skills were the least likely to demonstrate prodromal/overt psychosis at T3. Low scores on a T2 visual vigilance task also predicted T3 prodromal/overt psychosis, independently of the effect of T1 avoidance-anxiety scores. T1 dysregulation scores did not predict T3 prodromal/overt psychosis in a linear manner. Instead, the association between dysregulation and prodromal/overt psychosis was amplified by T2 levels of family organization, such that individuals with low dysregulation scores and low family organization scores were the most likely to exhibit T3 prodromal/overt psychosis.

CONCLUSIONS

Significant moderators of psychiatric risk in VCFS include verbal learning skills as well as levels of family organization, carrying implications for early identification and preventative treatment of youth with VCFS at highest risk for psychosis.

Developmental trajectories in 22q11.2 deletion

Chromosome 22q11.2 deletion syndrome (22q11.2DS), a neurogenetic condition, is the most common microdeletion syndrome affecting 1 in 2,000-4,000 live births and involving haploinsufficiency of ∼50 genes resulting in a multisystem disorder. Phenotypic expression is highly variable and ranges from severe life-threatening conditions to only a few associated features. Most common medical problems include: congenital heart disease, in particular conotruncal anomalies; palatal abnormalities, most frequently velopharyngeal incompetence (VPI); immunodeficiency; hypocalcemia due to hypoparathyroidism; genitourinary anomalies; severe feeding/gastrointestinal differences; and subtle dysmorphic facial features. The neurocognitive profile is also highly variable, both between individuals and during the course of development. From infancy onward, motor delays (often with hypotonia) and speech/language deficits are commonly observed. During the preschool and primary school ages, learning difficulties are very common. The majority of patients with 22q11.2DS have an intellectual level that falls in the borderline range (IQ 70-84), and about one-third have mild to moderate intellectual disability. More severe levels of intellectual disability are uncommon in children and adolescents but are more frequent in adults. Individuals with 22q11.2DS are at an increased risk for developing several psychiatric disorders including attention deficit with hyperactivity disorder (ADHD), autism spectrum disorder (ASD), anxiety and mood disorders, and psychotic disorders and schizophrenia. In this review, we will focus on the developmental phenotypic transitions regarding cognitive development in 22q11.2DS from early preschool to adulthood, and on the changing behavioral/psychiatric phenotype across age, on a background of frequently complex medical conditions.

White matter microstructural abnormalities of the cingulum bundle in youths with 22q11.2 deletion syndrome: associations with medication, neuropsychological function, and prodromal symptoms of psychosis

BACKGROUND

The 22q11.2 deletion syndrome (22q11.2DS) is regarded as an etiologically homogenous model for understanding neuroanatomic disruptions associated with a high risk for schizophrenia. This study utilized diffusion tensor imaging (DTI) to analyze white matter microstructure in individuals with 22q11.2DS. We focused on the cingulum bundle (CB), previously shown to be disrupted in patients with schizophrenia and associated with symptoms of psychosis.

METHODS

White matter microstructure was assessed in the anterior, superior, and posterior CB using the tractography algorithm in DTIStudio. Neuropsychological function, presence of prodromal symptoms of psychosis, and medication history were assessed in all participants.

RESULTS

Relative to controls, young adults with 22q11.2DS showed alterations in most DTI metrics of the CB. Alterations were associated with positive prodromal symptoms of psychosis. However, when individuals with 22q11.2DS were divided by usage of antipsychotics/mood stabilizers, the medicated and non-medicated groups differed significantly in axial diffusivity of the anterior CB and in fractional anisotropy of the superior CB. DTI metrics did not differ between the medicated group and the control group.

CONCLUSIONS

Results suggest that the microstructure of the CB is altered in individuals with 22q11.2DS, and that those alterations may underlie positive prodromal symptoms of psychosis. Our findings further provide preliminary evidence that antipsychotic/mood stabilizer usage may have a reparative effect on white matter microstructure in prodromal 22q11.2DS, independent of the potential effects of psychosis. Future studies of white matter pathology in individuals with 22q11.2DS should test for potential effects of medication on white matter microstructure.

Neurocognitive development in 22q11.2 deletion syndrome: comparison with youth having developmental delay and medical comorbidities

The 22q11.2 deletion syndrome (22q11DS) presents with medical and neuropsychiatric manifestations including neurocognitive deficits. Quantitative neurobehavioral measures linked to brain circuitry can help elucidate genetic mechanisms contributing to deficits. To establish the neurocognitive profile and neurocognitive 'growth charts', we compared cross-sectionally 137 individuals with 22q11DS ages 8-21 to 439 demographically matched non-deleted individuals with developmental delay (DD) and medical comorbidities and 443 typically developing (TD) participants. We administered a computerized neurocognitive battery that measures performance accuracy and speed in executive, episodic memory, complex cognition, social cognition and sensorimotor domains. The accuracy performance profile of 22q11DS showed greater impairment than DD, who were impaired relative to TD. Deficits in 22q11DS were most pronounced for face memory and social cognition, followed by complex cognition. Performance speed was similar for 22q11DS and DD, but 22q11DS individuals were differentially slower in face memory and emotion identification. The growth chart, comparing neurocognitive age based on performance relative to chronological age, indicated that 22q11DS participants lagged behind both groups from the earliest age assessed. The lag ranged from less than 1 year to over 3 years depending on chronological age and neurocognitive domain. The greatest developmental lag across the age range was for social cognition and complex cognition, with the smallest for episodic memory and sensorimotor speed, where lags were similar to DD. The results suggest that 22q11.2 microdeletion confers specific vulnerability that may underlie brain circuitry associated with deficits in several neuropsychiatric disorders, and therefore help identify potential targets and developmental epochs optimal for intervention.

Psychopathology in adults with 22q11 deletion syndrome and moderate and severe intellectual disability

BACKGROUND

22q11 deletion syndrome (22q11DS) is associated with mild or borderline intellectual disability (ID). There are hardly any reports on subjects with 22q11DS with moderate or severe ID, and therefore its behavioural and psychiatric characteristics are unknown.

METHOD

We describe behavioural and psychiatric characteristics of 33 adults with 22q11DS and a Full-Scale IQ (FSIQ) below 55. Participants were divided into two groups: one group having a FSIQ ≤ 55 caused by intellectual decline (n = 21) and one group with a FSIQ ≤ 55 who had always functioned at this level (n = 12).

RESULTS

High scores on psychopathology sub-scales were found for both subgroups. 22q11DS patients with intellectual decline showed higher rates of co-morbid psychopathology, particularly psychosis. Furthermore, psychosis and intellectual decline were positive correlated.

CONCLUSION

This is the first report addressing adult patients with 22q11DS and moderate to severe ID. Overall we found high levels of psychopathology with higher scores of psychopathology in the intellectual decline group. Life time psychosis seems to be related to deterioration.

Predicting reading comprehension academic achievement in late adolescents with velo-cardio-facial (22q11.2 deletion) syndrome (VCFS): a longitudinal study

BACKGROUND

The primary objective of the current study was to examine the childhood predictors of adolescent reading comprehension in velo-cardio-facial syndrome (VCFS). Although much research has focused on mathematics skills among individuals with VCFS, no studies have examined predictors of reading comprehension.

METHODS

69 late adolescents with VCFS, 23 siblings of youth with VCFS and 30 community controls participated in a longitudinal research project and had repeat neuropsychological test batteries and psychiatric evaluations every 3 years. The Wechsler Individual Achievement Test-2nd edition (WIAT-II) Reading Comprehension subtest served as our primary outcome variable.

RESULTS

Consistent with previous research, children and adolescents with VCFS had mean reading comprehension scores on the WIAT-II, that were approximately two standard deviations below the mean and word reading scores approximately one standard deviation below the mean. A more novel finding is that relative to both control groups, individuals with VCFS demonstrated a longitudinal decline in reading comprehension abilities yet a slight increase in word reading abilities. In the combined control sample, WISC-III FSIQ, WIAT-II Word Reading, WISC-III Vocabulary and CVLT-C List A Trial 1 accounted for 75% of the variance in Time 3 WIAT-II Reading Comprehension scores. In the VCFS sample, WISC-III FSIQ, BASC-Teacher Aggression, CVLT-C Intrusions, Tower of London, Visual Span Backwards, WCST Non-perseverative Errors, WIAT-II Word Reading and WISC-III Freedom from Distractibility index accounted for 85% of the variance in Time 3 WIAT-II Reading Comprehension scores. A principal component analysis with promax rotation computed on the statistically significant Time 1 predictor variables in the VCFS sample resulted in three factors: Word reading decoding/Interference control, Self-Control/Self-Monitoring and Working Memory.

CONCLUSIONS

Childhood predictors of late adolescent reading comprehension in VCFS differ in some meaningful ways from predictors in the non-VCFS population. These results offer some guidance for how best to consider intervention efforts to improve reading comprehension in the VCFS population.

Molecular genetic studies of ADHD and its candidate genes: a review

Attention-deficit/hyperactivity disorder (ADHD) is a common childhood-onset psychiatric disorder with high heritability. In recent years, numerous molecular genetic studies have been published to investigate susceptibility loci for ADHD. These results brought valuable candidates for further research, but they also presented great challenge for profound understanding of genetic data and general patterns of current molecular genetic studies of ADHD since they are scattered and heterogeneous. In this review, we presented a retrospective review of more than 300 molecular genetic studies for ADHD from two aspects: (1) the main achievements of various studies were summarized, including linkage studies, candidate-gene association studies, genome-wide association studies and genome-wide copy number variation studies, with a special focus on general patterns of study design and common sample features; (2) candidate genes for ADHD have been systematically evaluated in three ways for better utilization. The thorough summary of the achievements from various studies will provide an overview of the research status of molecular genetics studies for ADHD. Meanwhile, the analysis of general patterns and sample characteristics on the basis of these studies, as well as the integrative review of candidate ADHD genes, will propose new clues and directions for future experiment design.

Subthreshold psychotic symptoms in 22q11.2 deletion syndrome

OBJECTIVE

Chromosome 22q11.2 deletion syndrome (22q11DS) confers 25% risk for psychosis and is an invaluable window for understanding the neurobiological substrate of psychosis risk. The Structured Interview for Prodromal Syndromes (SIPS) is well validated in nondeleted populations for detecting clinical risk but has only recently been applied to 22q11DS. We assessed the largest 22q11DS cohort to date and report on SIPS implementation and symptoms elicited.

METHOD

The SIPS, including its 19 subscales, was administered to 157 individuals with 22q11DS aged 8 to 25 years. Youth and caregiver interviews were conducted and rated separately, then compared for agreement. Implementation of the SIPS in 22q11DS was challenging because of the prevalence of developmental delay and comorbid conditions. However, by explaining questions and eliciting examples, we were able to help youths and caregivers understand and respond appropriately. Consensus ratings were formulated and analyzed with itemwise and factor analysis.

RESULTS

Subthreshold symptoms were common, with 85% of individuals endorsing 1 or more. The most commonly rated items were ideational richness (47%) and trouble with focus and attention (44%). Factor analysis revealed a 3-factor solution with positive, negative, and disorganized components. Youth-caregiver comparisons suggested that youths report greater symptoms of perceptual abnormalities, suspiciousness, trouble with emotional expression, and bizarre thinking. Caregivers reported more impaired tolerance to normal stress, poor hygiene, and inattention.

CONCLUSION

The SIPS was adapted for 22q11DS through comprehensive and semi-structured administration methods, yielding a high prevalence of subthreshold psychotic symptoms. The significance and predictive validity of these symptoms require future longitudinal analysis.

Psychiatric disorders from childhood to adulthood in 22q11.2 deletion syndrome: results from the International Consortium on Brain and Behavior in 22q11.2 Deletion Syndrome

OBJECTIVE

Chromosome 22q11.2 deletion syndrome is a neurogenetic disorder associated with high rates of schizophrenia and other psychiatric conditions. The authors report what is to their knowledge the first large-scale collaborative study of rates and sex distributions of psychiatric disorders from childhood to adulthood in 22q11.2 deletion syndrome. The associations among psychopathology, intellect, and functioning were examined in a subgroup of participants.

METHOD

The 1,402 participants with 22q11.2 deletion syndrome, ages 6–68 years, were assessed for psychiatric disorders with validated diagnostic instruments. Data on intelligence and adaptive functioning were available for 183 participants ages 6 to 24 years.

RESULTS

Attention deficit hyperactivity disorder (ADHD) was the most frequent disorder in children (37.10%) and was overrepresented in males. Anxiety disorders were more prevalent than mood disorders at all ages, but especially in children and adolescents. Anxiety and unipolar mood disorders were overrepresented in females. Psychotic disorders were present in 41% of adults over age 25. Males did not predominate in psychotic or autism spectrum disorders. Hierarchical regressions in the subgroup revealed that daily living skills were predicted by the presence of anxiety disorders. Psychopathology was not associated with communication or socialization skills.

CONCLUSIONS

To the authors’ knowledge, this is the largest study of psychiatric morbidity in 22q11.2 deletion syndrome. It validates previous findings that this condition is one of the strongest risk factors for psychosis. Anxiety and developmental disorders were also prevalent. These results highlight the need to monitor and reduce the long-term burden of psychopathology in 22q11.2 deletion syndrome.

The schizophrenia/bipolar disorder candidate gene GNB1L is regulated in human temporal cortex by a cis-acting element located within the 3'-region

22q11.2 deletion syndrome (DS) is a complex developmental disorder with a high incidence of psychiatric illnesses, including schizophrenia and mood disorders. Recent studies have identified Guanine Nucleotide Binding Protein (G protein) Beta Polypeptide 1-Like (GNB1L), located within the 1.5 Mbp 22q11.2 DS critical region, as a candidate liability gene for schizophrenia and bipolar disorder. In this study, we used mRNA expression measurements in Han Chinese postmortem temporal cortex and linkage disequilibrium (LD) analysis to show that GNB1L is regulated by a cis-acting genetic variant within the 3'-region of the gene. Significantly, this variant is located within an LD block that contains all of the common SNPs previously shown to associate with schizophrenia and bipolar disorder in Han Chinese and Caucasian populations. Contrary to our expectations, re-analysis of previously published case-control study data in light of our mRNA expression results implies that the GNB1L high-expression allele is the risk allele for schizophrenia and bipolar disorder in the Han Chinese population.