Sunny X. Tang

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.

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.

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.

Contribution of Congenital Heart Disease to Neuropsychiatric Outcome in School-Age Children with 22q11.2 Deletion Syndrome

Children with 22q11.2 deletion syndrome (22q11DS) present with congenital heart disease (CHD) and high prevalence of psychiatric disorders and neurocognitive deficits. Although CHD has been implicated in neurodevelopment, its role in the neuropsychiatric outcome in 22q11DS is poorly understood. We investigated whether CHD contributes to the high prevalence of psychiatric disorders and neurocognitive impairments in 22q11DS. Fifty‐four children ages 8–14 years with 22q11DS and 16 age‐matched non‐deleted children with CHD participated. They were assessed using semi‐structured interviews and a Computerized Neurocognitive Battery. CHD status was assessed using available medical records. Prevalence of psychiatric disorders and cognitive profiles were compared among the groups. There were no significant differences between the prevalence of psychiatric disorders in the 22q11DS with and without CHD. In 22q11DS with CHD, the prevalence rates were 41% anxiety disorders, 37% ADHD and 71% psychosis spectrum. In 22q11DS without CHD, the rates were 33% anxiety disorders, 41% ADHD and 64% psychosis spectrum. In comparison, the non‐deleted CHD group had lower rates of psychopathology (25% anxiety disorders, 6% ADHD, and 13% psychosis spectrum). Similarly, the 22q11DS groups, regardless of CHD status, had significantly greater neurocognitive deficits across multiple domains, compared to the CHD‐only group. We conclude that CHD in this sample of children with 22q11.2DS does not have a major impact on the prevalence of psychiatric disorders and is not associated with increased neurocognitive deficits. These findings suggest that the 22q11.2 deletion status itself may confer significant neuropsychiatric vulnerability in this population.

The Psychosis Spectrum in 22q11.2 Deletion Syndrome Is Comparable to That of Nondeleted Youths

BACKGROUND Chromosome 22q11.2 deletion syndrome (22q11DS) is a promising model for studying psychosis risk. Direct comparisons of psychosis features between 22q11DS and nondeleted (ND) individuals are limited by inconsistency and small samples. In the largest study to date, we compare 22q11DS to ND in comorbidities, functioning, cognition, and psychosis features across the full range of overall severity. METHODS ND youths (n = 150) ages 9 to 24 years were matched to 22q11DS individuals (n = 150) on age and sex, stratifying for presence of psychosis spectrum disorder. Individuals were evaluated for psychosis using the Structured Interview for Prodromal Syndromes, and for attention-deficit/hyperactivity, substance-related, and mood disorders. Differential item functioning analysis addressed whether 22q11DS differs from ND in the probability of clinically significant ratings while holding constant the overall level of psychosis. RESULTS Onset of psychosis proneness was similar among 22q11DS (mean: 11.0 years) and ND (mean: 12.1 years) individuals. Accounting for higher overall psychosis symptoms, 22q11DS participants were still more likely to manifest impaired stress tolerance, avolition, and ideational richness; ND individuals were more likely to exhibit unusual thoughts, persecutory ideas, and bizarre thinking. Cognition was impaired in 22q11DS, but it did not correlate with symptoms except ideational richness. Comorbid anxiety disorders were more likely in psychosis spectrum 22q11DS; substance-related disorders were more likely in ND. Global assessment of function was similar in 22q11DS and ND individuals, except among those with low total Structured Interview for Prodromal Syndromes scores. CONCLUSIONS Individuals with 22q11DS share overarching similarities with ND individuals in psychosis symptoms and age of onset for psychosis proneness; this continues to support the 22q11DS model as a valuable window into mechanisms contributing to psychosis.

Impact of Psychiatric Comorbidity and Cognitive Deficit on Function in 22q11.2 Deletion Syndrome

OBJECTIVE Presence of psychiatric comorbidity is associated with poor functioning and is an important consideration in treatment. Many individuals with 22q11.2 deletion syndrome (22q11DS) develop comorbid psychiatric disorders, yet its pattern and impact on functioning have not been formally investigated. In this cross-sectional study, we examined the relationship between comorbid psychopathology and neurocognitive deficits and their association with global functioning. We hypothesized that higher psychiatric burden and psychosis-spectrum features would be associated with reduced functioning and increased neurocognitive deficits. METHOD The cohort included 171 individuals with 22q11DS and mean (SD) age of 17.4 (8.1) years, recruited from a tertiary childrens hospital and nationally through social media between September 2010 and December 2013. Psychiatric diagnoses and functioning were assessed using semistructured interviews and the Global Assessment of Functioning (GAF) scale, respectively. On the basis of psychopathology and number of comorbid diagnoses, participants were assigned to unaffected (n = 32), nonpsychosis spectrum (n = 24), nonpsychosis spectrum-plus (n = 15), psychosis spectrum (n = 29), and psychosis spectrum-plus (n = 71) groups. Executive function, episodic memory, complex cognition, social cognition, and praxis speed were assessed using a computerized neurocognitive battery (CNB). Cognitive profile and GAF scores were compared among the groups, and the association of GAF with cognitive performance and psychopathology was examined. RESULTS We observed high rates of comorbid psychiatric disorders. Approximately 50% of the participants had ≥ 2 diagnoses. Psychosis spectrum disorders were most frequently comorbid with other disorders. GAF score was progressively worse with increased psychiatric burden. Mean (SD) GAF score for the unaffected group (81.1 [8.9]) was significantly different from those of nonpsychosis spectrum (68.6 [12.1]), nonpsychosis spectrum-plus (63.4 [8.8]), psychosis spectrum (58.7 [13.1]), or psychosis spectrum-plus (55.5 [13.3]) (P < .05) groups. All groups performed poorly and were comparable to each other on the CNB (P = .273). Notably, verbal memory (P = .003), spatial processing (P = .001), and parent education level (P < .001) were significantly associated with GAF. CONCLUSIONS Individuals with 22q11DS have high rates of comorbid psychiatric disorders and diffuse cognitive deficits regardless of psychiatric burden. Those with psychotic spectrum disorders and comorbid psychiatric disorders are at an increased risk for poor overall functioning.

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.

Emergent, remitted and persistent psychosis-spectrum symptoms in 22q11.2 deletion syndrome

Individuals with 22q11.2 deletion syndrome (22q11DS) are at markedly elevated risk for schizophrenia-related disorders. Stability, emergence, remission and persistence of psychosis-spectrum symptoms were investigated longitudinally. Demographic, clinical and cognitive predictors of psychosis were assessed. Prospective follow-up over 2.8 years was undertaken in 75 individuals with 22q11DS aged 8–35 years. Mood, anxiety, attention-deficit hyperactivity disorders and psychosis-spectrum symptoms were assessed with the Kiddie-Schedule for Affective Disorders and Schizophrenia and Scale of Prodromal Symptoms (SOPS). Four domains of cognition were evaluated with the Penn Computerized Neurocognitive Battery (executive functioning, memory, complex cognition and social cognition). Psychotic disorder or clinically significant SOPS-positive ratings were consistently absent in 35%, emergent in 13%, remitted in 22% and persistent in 31% of participants. Negative symptoms and functional impairment were found to be predictive of the emergence of positive psychosis-spectrum symptoms and to reflect ongoing deficits after remission of positive symptoms. Dysphoric mood and anxiety were predictive of emergent and persistent-positive psychosis-spectrum symptoms. Lower baseline global cognition and greater global cognitive decline were predictive of psychosis-spectrum outcomes but no particular cognitive domain stood out as being significantly more discriminating than others. Our findings suggest that negative symptoms, functioning and dysphoric mood are important predictors of psychosis risk in this population.

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.

Longitudinal perspectives on the psychosis spectrum in 22q11.2 deletion syndrome

The prevalence of psychotic disorders in individuals with 22q11.2 Deletion Syndrome (22q11DS) reaches 25–35% in young adulthood and may provide a neurogenetic model for clinical risk of psychotic disorders in the general population. This review focuses on prospective longitudinal studies in 22q11DS, which capture fluctuations in psychosis symptoms over time and may provide insights into potential demographic, clinical, cognitive, and neuroimaging predictors of psychosis‐spectrum outcomes in the general population. Findings are compared and contrasted with those from idiopathic psychosis‐spectrum populations. Onset of psychotic disorders in 22q11DS can occur over a wide range of ages, peaking in late adolescence. Symptoms may be gradually progressive or episodic in nature, highlighting the importance and challenge of risk and resilience prediction models. Converging results suggest that psychosis‐spectrum outcomes in 22q11DS are predicted by lower baseline functioning, higher baseline psychosis‐spectrum symptoms, presence of mood disturbance or anxiety, and lower baseline and subsequent decline in global measures of cognition. Predictors of transition to threshold psychotic disorders and ages of onset are similar in idiopathic clinical risk. They also share similarly global cognitive deficits, but not to the same extent as in 22q11DS. While neuroimaging studies in idiopathic clinical risk suggest loss of prefrontal gray matter, there is no consistent evidence yet emerging in the limited literature in 22q11DS. Interventional efforts in 22q11DS aimed at halting progression to psychosis or mitigating outcomes in early psychosis may be best implemented during the adolescent age range. Collaborative longitudinal efforts may help to address existing gaps in our understanding.