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.

Cognitive decline preceding the onset of psychosis in patients with 22q11.2 deletion syndrome

IMPORTANCE

Patients with 22q11.2 deletion syndrome (22q11DS) have an elevated (25%) risk of developing schizophrenia. Recent reports have suggested that a subgroup of children with 22q11DS display a substantial decline in cognitive abilities starting at a young age.

OBJECTIVE

To determine whether early cognitive decline is associated with risk of psychotic disorder in 22q11DS.

DESIGN, SETTING, AND PARTICIPANTS

Prospective longitudinal cohort study. As part of an international research consortium initiative, we used the largest data set of intelligence (IQ) measurements in patients with 22q11DS reported to date to investigate longitudinal IQ trajectories and the risk of subsequent psychotic illness. A total of 829 patients with a confirmed hemizygous 22q11.2 deletion, recruited through 12 international clinical research sites, were included. Both psychiatric assessments and longitudinal IQ measurements were available for a subset of 411 patients (388 with ≥1 assessment at age 8-24 years).

MAIN OUTCOMES AND MEASURES

Diagnosis of a psychotic disorder, initial IQ, longitudinal IQ trajectory, and timing of the last psychiatric assessment with respect to the last IQ test.

RESULTS

Among 411 patients with 22q11DS, 55 (13.4%) were diagnosed as having a psychotic disorder. The mean (SD) age at the most recent psychiatric assessment was 16.1 (6.2) years. The mean (SD) full-scale IQ at first cognitive assessment was lower in patients who developed a psychotic disorder (65.5 [12.0]) compared with those without a psychotic disorder (74.0 [14.0]). On average, children with 22q11DS showed a mild decline in IQ (full-scale IQ, 7.04 points) with increasing age, particularly in the domain of verbal IQ (9.02 points). In those who developed psychotic illness, this decline was significantly steeper (P < .001). Those with a negative deviation from the average cognitive trajectory observed in 22q11DS were at significantly increased risk for the development of a psychotic disorder (odds ratio = 2.49; 95% CI, 1.24-5.00; P = .01). The divergence of verbal IQ trajectories between those who subsequently developed a psychotic disorder and those who did not was distinguishable from age 11 years onward.

CONCLUSIONS AND RELEVANCE

In 22q11DS, early cognitive decline is a robust indicator of the risk of developing a psychotic illness. These findings mirror those observed in idiopathic schizophrenia. The results provide further support for investigations of 22q11DS as a genetic model for elucidating neurobiological mechanisms underlying the development of psychosis.

Movement disorders and other motor abnormalities in adults with 22q11.2 deletion syndrome

Movement abnormalities are frequently reported in children with 22q11.2 deletion syndrome (22q11.2DS), but knowledge in this area is scarce in the increasing adult population. We report on five individuals illustrative of movement disorders and other motor abnormalities in adults with 22q11.2DS. In addition to an increased susceptibility to neuropsychiatric disorders, seizures, and early-onset Parkinson disease, the underlying brain dysfunction associated with 22q11.2DS may give rise to an increased vulnerability to multiple movement abnormalities, including those influenced by medications. Movement abnormalities may also be secondary to treatable endocrine diseases and congenital musculoskeletal abnormalities. We propose that movement abnormalities may be common in adults with 22q11.2DS and discuss the implications and challenges important to clinical practice.

A Practical Approach to Hypocalcaemia in Children

Hypocalcaemia is one of the commonest disorders of mineral metabolism seen in children and may be a consequence of several different aetiologies. These include a lack of secretion or function of parathyroid hormone, disorders of vitamin D metabolism and abnormal function of the calcium-sensing receptor. A practical approach to the investigation, diagnosis and subsequent management of hypocalcaemic disorders is presented.

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.

22q11.2 Deletion syndrome is associated with increased perioperative events and more complicated postoperative course in infants undergoing infant operative correction of truncus arteriosus communis or interrupted aortic arch

OBJECTIVE

The effect of genotype on the outcomes of infant cardiac operations has not been well established. The purpose of the present study was to investigate the effect of 22q11.2 deletion (22q11del) on infants with truncus arteriosus communis (TA) and interrupted aortic arch (IAA) undergoing operative correction during infancy.

METHODS

We conducted a retrospective cohort study of all infants who had undergone operative correction of TA or IAA at the Children's Hospital of Philadelphia from 1995 to 2007, comparing the perioperative outcomes (hospital length of stay, intensive care, mechanical ventilation, risk of cardiac and noncardiac events, number of consultations, and number of discharge medications) by 22q11del status.

RESULTS

A total of 104 patients were studied (55 with TA and 49 with IAA), of whom 40 (38%) were 22q11del positive. The 22q11del status was unknown in 9 (7 with TA and 2 with IAA). In patients with known deletion status, those with 22q11del had a longer hospital and intensive care length of stay. Subjects with 22q11del also required more frequent operative reintervention and more consultations and were prescribed more medications at discharge. No significant difference was found in method of feeding between those with and without 22q11del at discharge.

CONCLUSIONS

In this study, 22q11del is associated with perioperative outcomes in infants undergoing operative correction of TA and IAA, with longer hospital stays and greater resource utilization in the perioperative period. These findings should inform counseling and risk stratification and warrant additional study to identify genotype-specific management strategies to improve outcomes.

Psychiatric disorders in 22q11.2 deletion syndrome are prevalent but undertreated

BACKGROUND

Chromosome 22q11.2 deletion syndrome (22q11DS) is a common genetic disorder with high rates of psychosis and other psychopathologies, but few studies discuss treatment. Our aim was to characterize the prevalence and treatment of major psychiatric illnesses in a well-characterized sample of individuals with 22q11DS.

METHOD

This was a cross-sectional study of 112 individuals aged 8 to 45 years with a confirmed diagnosis of 22q11DS. Each participant was administered a modified Schedule for Affective Disorders and Schizophrenia for School-Age Children (K-SADS) and the Structured Interview for Prodromal Syndromes (SIPS). Phenotypes assessed were threshold and subthreshold psychosis, depression, mania, generalized and separation anxiety, obsessions/compulsions, inattention/hyperactivity and substance use. Histories of mental health care and current psychotropic treatment were obtained.

RESULTS

Psychopathology was common, with 79% of individuals meeting diagnostic criteria for a disorder at the time of assessment. Diagnoses of psychosis were made in 11% of cases, attenuated positive symptom syndrome (APS) in 21%, and 47% experienced significant subthreshold symptoms. Peak occurrence of psychosis risk was during adolescence (62% of those aged 12-17 years). Criteria for a mood disorder were met by 14%, for anxiety disorder 34% and for attention deficit hyperactivity disorder (ADHD) 31%. Mental health care had been received by 63% of individuals in their lifetime, but only 40% continued therapy and 39% used psychotropics. Antipsychotics were used by 42% of participants with psychosis and none of the participants with APS. Half of those at risk for psychosis were receiving no mental health care.

CONCLUSIONS

Psychopathology is common in 22q11DS but is not adequately treated or clinically followed. Particular attention should be paid to subthreshold psychotic symptoms, especially in adolescents.

The 22q11.2 deletion syndrome as a window into complex neuropsychiatric disorders over the lifespan

Evidence is rapidly accumulating that rare, recurrent copy number variants represent large effect risk factors for neuropsychiatric disorders. 22q11.2 deletion syndrome (22q11DS) (velocardiofacial syndrome or DiGeorge syndrome) is the most common known contiguous gene deletion syndrome and is associated with diverse neuropsychiatric disorders across the life span. One of the most intriguing aspects of the syndrome is the variability in clinical and cognitive presentation: children with 22q11DS have high prevalence of autism spectrum, attention deficit, and anxiety disorders, as well as psychotic-like features, and up to 30% of adolescents and adults develop schizophrenia-like psychosis. Recently, cases of early-onset Parkinson's disease in adults have been reported, collectively suggesting a role for disrupted dopaminergic neurotransmission in the observed neuropsychiatric phenotypes. There is also some evidence that 22q11DS-associated autism spectrum disorder and schizophrenia represent two unrelated phenotypic manifestations, consistent with a neuropsychiatric pleiotropy model. This genetic lesion thus provides a unique model for the discovery of specific genomic risk and (potentially) protective factors for neuropsychiatric disease. Here, we provide an overview of neuropsychiatric findings to date, which highlight the value of this syndrome in mapping the developmental trajectory of dimensional phenotypes that traverse multiple diagnostic categories. Potential sources of genetic variability that may contribute to the disorder's heterogeneous presentation are reviewed. Because of its known genetic etiology, animal models can readily be developed that recapitulate specific aspects of the syndrome. Future research directions involve translational models and potential for drug screenable targets in the context of this human model system.

Children with chromosome 22q11.2 deletion syndrome exhibit impaired spatial working memory

Individuals with chromosome 22q11.2 deletion syndrome (22q11.2DS) have been shown to have impairments in processing spatiotemporal information. The authors examined whether children with 22q11.2DS exhibit impairments in spatial working memory performance due to these weaknesses, even when controlling for maintenance of attention. Children with 22q11.2DS (n  =  47) and typically developing controls (n  =  49) ages 6-15 years saw images within a grid and after a delay, then indicated the positions of the images in the correct temporal order. Children with 22q11.2DS made more spatial and temporal errors than controls. Females with 22q11.2DS made more spatial and temporal errors than males. These results extend findings of impaired spatiotemporal processing into the memory domain in 22q11.2DS by documenting their influence on working memory performance.

Gyrification differences in children and adolescents with velocardiofacial syndrome and attention-deficit/hyperactivity disorder: a pilot study

We used magnetic resonance imaging to investigate brain gyrification patterns between 19 children with attention-deficit/hyperactivity disorder (ADHD), 9 children with velocardiofacial syndrome (VCFS), and 23 control children. We found that VCFS is associated with widespread decreases in gyrification. In ADHD, we found minor differences from control children. No evidence was found for common gyrification patterns between VCFS and ADHD children.

Premorbid adjustment and schizophrenia in individuals with 22q11.2 deletion syndrome

The literature on idiopathic schizophrenia has consistently reported that poor premorbid functioning precedes onset of psychosis. Individuals with 22q11.2 deletion syndrome (22q11.2DS) are at heightened risk of developing schizophrenia. The present study examined the relationship between adult-onset schizophrenia and social and academic functioning across childhood and early adolescent development in 22q11.2DS.

METHOD

Premorbid adjustment in social and academic domains during childhood (ages 5-11 years) and early adolescence (ages 12-15 years) of 103 adults with 22q11.2DS was assessed using the Premorbid Adjustment Scale (PAS). Linear mixed-models were used to compare PAS scores between the 43 subjects who later developed schizophrenia and the 60 subjects who did not.

RESULTS

Social functioning and academic functioning deteriorated from childhood to early adolescence among those who later developed schizophrenia compared to stable functioning, on average, in those who did not later develop a psychotic disorder. Those who developed schizophrenia had significantly higher PAS scores (indicating poorer functioning) in social (β=0.118, 95% CI: 0.046-0.189) and academic (β=0.072, 95% CI: 0.015-0.129) domains between childhood and early adolescence, independent of the presence of intellectual disability. The two groups had similar PAS scores during childhood.

CONCLUSION

Consistent with the literature on idiopathic schizophrenia, deterioration in social and academic functioning between childhood and early adolescence preceded onset of schizophrenia in this cohort of 22q11.2DS patients, regardless of functioning at baseline. These findings suggest that monitoring for changes in functioning, in addition to emergence of typical symptoms, may help to prevent delays in diagnosis and treatment of major psychotic illness in 22q11.2DS.

Hearing loss in a mouse model of 22q11.2 Deletion Syndrome

22q11.2 Deletion Syndrome (22q11DS) arises from an interstitial chromosomal microdeletion encompassing at least 30 genes. This disorder is one of the most significant known cytogenetic risk factors for schizophrenia, and can also cause heart abnormalities, cognitive deficits, hearing difficulties, and a variety of other medical problems. The Df1/+ hemizygous knockout mouse, a model for human 22q11DS, recapitulates many of the deficits observed in the human syndrome including heart defects, impaired memory, and abnormal auditory sensorimotor gating. Here we show that Df1/+ mice, like human 22q11DS patients, have substantial rates of hearing loss arising from chronic middle ear infection. Auditory brainstem response (ABR) measurements revealed significant elevation of click-response thresholds in 48% of Df1/+ mice, often in only one ear. Anatomical and histological analysis of the middle ear demonstrated no gross structural abnormalities, but frequent signs of otitis media (OM, chronic inflammation of the middle ear), including excessive effusion and thickened mucosa. In mice for which both in vivo ABR thresholds and post mortem middle-ear histology were obtained, the severity of signs of OM correlated directly with the level of hearing impairment. These results suggest that abnormal auditory sensorimotor gating previously reported in mouse models of 22q11DS could arise from abnormalities in auditory processing. Furthermore, the findings indicate that Df1/+ mice are an excellent model for increased risk of OM in human 22q11DS patients. Given the frequently monaural nature of OM in Df1/+ mice, these animals could also be a powerful tool for investigating the interplay between genetic and environmental causes of OM.

The diverse clinical features of chromosome 22q11.2 deletion syndrome (DiGeorge syndrome)

A 2-year-old boy with chromosome 22q11.2 deletion syndrome was referred for recurrent sinopulmonary infections. He was diagnosed shortly after birth by a fluorescence in situ hybridization test that was performed due to interrupted aortic arch type B. He had no hypocalcemia, and his recovery from cardiac repair was uneventful. He had difficulty feeding and gained weight slowly, but, otherwise, there were no concerns during his first year of life. At 15 months of age, he began to develop significant otitis media and bronchitis. He was hospitalized once for pneumonia at 18 months of age and has never been off antibiotics for more than 1 week since then. He has not had any previous immunologic evaluation. Recurrent sinopulmonary infections in a child with chromosome 22q11.2 deletion syndrome can have the same etiologies as in any other child. Atopy, anatomic issues, cystic fibrosis, and new environmental exposures could be considered in this setting. Early childhood can be problematic for patients with chromosome 22q11.2 deletion syndrome due to unfavorable drainage of the middle ear and sinuses. Atopy occurs at a higher frequency in 22q11.2 deletion syndrome, and these children also have a higher rate of gastroesophageal reflux and aspiration than the general population. As would be appropriate for any child who presents with recurrent infections at 2 years of age, an immunologic evaluation should be performed. In this review, we will highlight recent findings and new data on the management of children and adults with chromosome 22q11.2 deletion syndrome.

Anti-infective prophylaxis for primary immunodeficiencies: what is done in Italian Primary Immunodeficiency Network centers (IPINet) and review of the literature

Primary immunodeficiencies (PIDs) are rare diseases characterized by an increased susceptibility to infections. Early diagnosis and appropriate treatment are critical for reducing morbidity and mortality. Based on available data, the efficacy of antibiotic administration for the prophylaxis of infections remains uncertain, and recommendations supporting this practice are poor. The use of antimicrobial prophylaxis is mainly based on single institution-specific experience without controlled measurements of patient safety and quality health outcomes. To address this issue an Italian Network on Primary Immunodeficiencies (IPINet) has been set up in 1999 within the Italian Association of Pediatric Hematology and Oncology (AIEOP) to increase the awareness of these disorders among physicians. Further, diagnostic and treatment guideline recommendations have been established to standardize the best clinical assistance to all patients, including antibiotic prophylaxis, and for a national epidemiologic monitoring of PIDs. The aim of this review is not only to give a scientific update on the use of antimicrobial prophylaxis in selected congenital immunological disorders but also to draw a picture of this practice in the context of the Italian Primary Immunodeficiency Network (IPINet). Controlled multicenter studies are necessary to establish if, when and how you should start an efficacious antimicrobial prophylaxis.

Discrepancies in parent and teacher ratings of social-behavioral functioning of children with chromosome 22q11.2 deletion syndrome: implications for assessment

Children with 22q11.2 deletion syndrome exhibit high rates of social-behavioral problems, particularly in the internalizing domain, indicating an area in need of intervention. The current investigation was designed to obtain information regarding parent and teacher ratings of the social-emotional behavior of children with 22q11DS. Using the Child Behavior Checklist (CBCL), the sample included 67 children with 22q11DS and 59 control subjects. Results indicated significant differences in social-behavioral functioning of children with 22q11DS, as compared to a control group, based on rater type. Specifically, parents reported more difficulties with internalizing problems, withdrawal, and social problems in children with 22q11DS. In contrast, teachers perceived few differences between children with 22q11DS and unaffected children. Correlational analyses indicated weak concordance between parent and teacher reports, with no significant correlations on any of three summary scales. The findings support the use of multiple methods of assessment and multiple informants when collecting information regarding the social-behavioral functioning of children with 22q11DS, and that interpretations based on only one informant/setting need to be made cautiously.

The longitudinal course of attention deficit/hyperactivity disorder in velo-cardio-facial syndrome

OBJECTIVE

To evaluate predictors of persistence of attention deficit/hyperactivity disorder (ADHD) in a large sample of children with velo-cardio-facial syndrome (VCFS) with and without ADHD followed prospectively into adolescence.

STUDY DESIGN

Children with VCFS with (n = 37) and without (n = 35) ADHD who were on average 11 years old at the baseline assessment and 15 years old at the follow-up assessment were comprehensively assessed with structured diagnostic interviews and assessments of behavioral, cognitive, social, school, and family functioning. Control participants both with and without ADHD were also followed prospectively.

RESULTS

In adolescence, 65% of children with VCFS continued to have findings consistent with ADHD. Childhood predictors of persistence were higher rates of familial ADHD, having childhood depression, having higher levels of hyperactivity, and a larger number of intrusion errors on a verbal list learning test at baseline. Approximately 15% of children with VCFS who did not have ADHD at Time 1 met diagnostic criteria for ADHD at Time 2. All of these children had subthreshold ADHD symptoms at Time 1.

CONCLUSIONS

These findings prospectively confirm that persistence of ADHD into adolescence in VCFS is predicted by childhood variables that have been previously documented in the non-VCFS ADHD literature.

Altered auditory processing in frontal and left temporal cortex in 22q11.2 deletion syndrome: a group at high genetic risk for schizophrenia

In order to investigate electroencephalographic (EEG) biomarkers of auditory processing for schizophrenia, we studied a group with a well known high-risk profile: patients with 22q11.2 deletion syndrome (22q11 DS) have a 30% risk of developing schizophrenia during adulthood. We performed high-density EEG source imaging to measure auditory gating of the P50 component of the evoked potential and middle to late latency auditory processing in 21 participants with the 22q11.2 deletion and 17 age-matched healthy controls. While we found no indication of altered P50 suppression in 22q11 DS, we observed marked differences for the first N1 component with increased amplitudes on central electrodes, corresponding to increased activations in dorsal anterior cingulate and medial frontal cortex. We also found a left lateralized reduction of activation of primary and secondary auditory cortex during the second N1 (120ms) and the P2 component in 22q11 DS. Our results show that sensory gating and activations until 50ms were preserved in 22q11 DS, while impairments appear at latencies that correspond to higher order auditory processing. While the increased activation of cingulate and medial frontal cortex could reflect developmental changes in 22q11 DS, the reduced activity seen in left auditory cortex might serve as a biomarker for the development of schizophrenia, if confirmed by longitudinal research protocols.

A definite case of (L)-carbocisteine-induced pneumonia with CATCH22 syndrome

A 32-year-old male with CATCH22 syndrome presented with a high fever and productive cough after taking drugs for acute bronchitis, including (L)-carbocisteine. Chest radiography revealed ground-glass opacities in the bilateral lung fields. He had a history of similar pneumonia. Under the assumption of drug-induced pneumonia, or bacterial or viral pneumonia, all drugs including (L)-carbocisteine were discontinued, and antibiotics were started. A drug-induced lymphocyte stimulation test was positive only for (L)-carbocisteine. The only drug in common between this and the previous episode of pneumonia was (L)-carbocisteine. We thus concluded that this was a definite case of (L)-carbocisteine-induced pneumonia in a patient with CATCH22 syndrome.

First seizure as late presentation of velo-cardio-facial syndrome

Congenital hypoparathyroidism caused by velo-cardio-facial syndrome (VCFS) typically presents with hypocalcemia in the neonatal period associated with other characteristic findings. We report the case of an 8-year-old boy presenting a hypocalcemic seizure (ionized calcium, 0.65 mM); he had a history of velopharyngeal insufficiency and late development with language impairment; at presentation, minor dysmorphic features were noticed. Laboratory evaluation revealed a parathormone level of <1.0 pg/mL. VCFS was confirmed by fluorescence in situ hybridization study revealing the 22q11.2 deletion. High levels of calcium administration were needed to normalize serum calcium. In this case, signs of hypoparathyroidism only developed in late childhood, and the patient, despite the minor clinical signs of VCFS, remained symptom-free. He presented no cardiac malformations, immunologic abnormalities, or renal dysfunction often associated with this diagnosis. In a child with hypocalcemia, considering the hypothesis of VCFS, even if there are no other manifestations, is important both for clinical diagnosis and management and for genetic counseling.

An adult case of 22q11.2 deletion syndrome diagnosed in a 36-year-old woman with hypocalcemia caused by hypoparathyroidism and Hashimoto's thyroiditis

22q11.2 Deletion syndrome is recognized to be a major cause of congenital hypoparathyroidism, and affected patients exhibit a range of autoimmune characteristics. The syndrome becomes apparent in early childhood and is rarely diagnosed in adulthood. This report describes an adult case of 22q11.2 deletion syndrome first diagnosed in a 36-year-old woman with hypocalcemia caused by hypoparathyroidism and Hashimoto's thyroiditis. It is important to diagnose 22q11.2 deletion syndrome in adults because such patients are still at high risk for developing treatable diseases, such as hypocalcemia and autoimmune diseases.

Social cognition in 22q11.2 microdeletion syndrome: relevance to psychosis?

22q11.2 deletion syndrome (22qDS) represents one of the largest known genetic risk factors for schizophrenia. Approximately 30% of individuals with 22qDS develop psychotic illness in adolescence or young adulthood. Given that deficits in social cognition are increasingly viewed as a central aspect of idiopathic schizophrenia, we sought to investigate abilities in this domain as a predictor of psychotic symptoms in 22qDS participants. We assessed multiple domains of social and non-social cognition in 22qDS youth to: 1) characterize performance across these domains in 22qDS, and identify whether 22qDS participants fail to show expected patterns of age-related improvements on these tasks; and 2) determine whether social cognition better predicts positive and negative symptoms than does non-social cognition. Task domains assessed were: emotion recognition and differentiation, Theory of Mind (ToM), verbal knowledge, visuospatial skills, working memory, and processing speed. Positive and negative symptoms were measured using scores obtained from the Structured Interview for Prodromal Symptoms (SIPS). 22qDS participants (N=31, mean age: 15.9) showed the largest impairment, relative to healthy controls (N=31, mean age: 15.6), on measures of ToM and processing speed. In contrast to controls, 22qDS participants did not show age-related improvements on measures of working memory and verbal knowledge. Notably, ToM performance was the best predictor of positive symptoms in 22qDS, accounting for 39% of the variance in symptom severity. Processing speed emerged as the best predictor of negative symptoms, accounting for 37% of the variance in symptoms. Given that ToM was a robust predictor of positive symptoms in our sample, these findings suggest that social cognition may be a valuable intermediate trait for predicting the development of psychosis.

An examination of the relationship of anxiety and intelligence to adaptive functioning in children with chromosome 22q11.2 deletion syndrome

OBJECTIVE

This study investigates the relationship between anxiety symptoms and adaptive function in children with chromosome 22q11.2 deletion syndrome (22q11.2DS).

METHODS

Seventy-eight children between 7 and 14 years of age with 22q11.2DS and 36 typically developing (TD) children without known genetic syndromes participated in a larger study of neurocognition. Parents completed questionnaires about their child's anxiety symptoms (Behavior Assessment System for Children, 2nd edition [BASC-2] and Spence Children's Anxiety Scale [SCAS]) and adaptive functioning (BASC-2 and Adaptive Behavior Assessment System, 2nd edition). Within the 22q11.2DS group, different DSM-IV anxiety domains were also analyzed using SCAS subscales.

RESULTS

Based on parent report, 19% of children with 22q11.2DS had a prior diagnosis of an anxiety disorder versus 58% with at least 1 elevated anxiety score (BASC-2 or SCAS). Mean BASC-2 anxiety scores were significantly higher in 22q11.2DS (55.6 ± 12.5) than in TD children (48.3 ± 10; p = .003), and a greater percentage of children with 22q11.2DS (37%) had an elevated BASC-2 anxiety scores compared with TD children (14%; p = .01). Higher anxiety scores were related to lower adaptive function (r = -.27; p = .015), but there was no relationship between Wechsler Intelligence Scale for Children, 4th edition Full Scale Intelligence Quotient and BASC-2 adaptive skills (r = -.06; p = .6) in the 22q11.2DS group. For the individual SCAS anxiety subscales, panic-agoraphobia (r = -.38; p = .03), physical injury (r = -.34; p = .05), and obsessive-compulsive disorder (r = -.47; p = .005) were significantly negatively related to adaptive function in 22q11.2DS.

CONCLUSION

Despite the known risk, anxiety is underidentified in children with 22q11.2DS. The presence of anxiety symptoms, but not intelligence levels, in children with 22q11.2DS negatively correlated with adaptive function and impacts everyday living skills.

An examination of the relationship of anxiety and intelligence to adaptive functioning in children with chromosome 22q11.2 deletion syndrome

OBJECTIVE

This study investigates the relationship between anxiety symptoms and adaptive function in children with chromosome 22q11.2 deletion syndrome (22q11.2DS).

METHODS

Seventy-eight children between 7 and 14 years of age with 22q11.2DS and 36 typically developing (TD) children without known genetic syndromes participated in a larger study of neurocognition. Parents completed questionnaires about their child's anxiety symptoms (Behavior Assessment System for Children, 2nd edition [BASC-2] and Spence Children's Anxiety Scale [SCAS]) and adaptive functioning (BASC-2 and Adaptive Behavior Assessment System, 2nd edition). Within the 22q11.2DS group, different DSM-IV anxiety domains were also analyzed using SCAS subscales.

RESULTS

Based on parent report, 19% of children with 22q11.2DS had a prior diagnosis of an anxiety disorder versus 58% with at least 1 elevated anxiety score (BASC-2 or SCAS). Mean BASC-2 anxiety scores were significantly higher in 22q11.2DS (55.6 ± 12.5) than in TD children (48.3 ± 10; p = .003), and a greater percentage of children with 22q11.2DS (37%) had an elevated BASC-2 anxiety scores compared with TD children (14%; p = .01). Higher anxiety scores were related to lower adaptive function (r = -.27; p = .015), but there was no relationship between Wechsler Intelligence Scale for Children, 4th edition Full Scale Intelligence Quotient and BASC-2 adaptive skills (r = -.06; p = .6) in the 22q11.2DS group. For the individual SCAS anxiety subscales, panic-agoraphobia (r = -.38; p = .03), physical injury (r = -.34; p = .05), and obsessive-compulsive disorder (r = -.47; p = .005) were significantly negatively related to adaptive function in 22q11.2DS.

CONCLUSION

Despite the known risk, anxiety is underidentified in children with 22q11.2DS. The presence of anxiety symptoms, but not intelligence levels, in children with 22q11.2DS negatively correlated with adaptive function and impacts everyday living skills.

Behavioural phenotypes and special educational needs: is aetiology important in the classroom?

BACKGROUND

A number of genetic conditions with associated intellectual disability and/or special educational needs have increasingly well-defined behavioural phenotypes. Thus, the concept of 'behavioural phenotype' and aetiology of intellectual disability may be important with regard to school-based interventions.

METHOD

The evidence for distinctive cognitive and behavioural aspects of five of the most common genetic syndromes (Down syndrome, fragile X syndrome, Williams syndrome, Prader-Willi syndrome and velo-cardio-facial syndrome) associated with special educational needs is reviewed with respect to key studies and findings. The possible utility of aetiology-related interventions in education is discussed with reference to arguments for and against such approaches with respect to published guidelines and published research.

RESULTS

Behavioural phenotypes are probabilistic and many children with a specific genetic syndrome will share commonalities with other children with other genetic syndromes and within syndrome variability is not uncommon. There is evidence that teachers and parents have limited knowledge of aspects of the proposed cognitive and behaviour profiles associated with the reviewed syndromes. While there are published guidelines in the area of learning and behaviour for each of the five reviewed syndromes there is a limited amount of evidence of the efficacy of such approaches in school settings.

CONCLUSION

It is likely that knowing the aetiology of a child's special educational needs will be helpful for staff who work in school settings in relation to cognitive and behavioural implications. However, how such knowledge might inform teaching practice or behavioural interventions has not been studied. A model is proposed that might help inform educators about the possible role of aetiology in the classroom.