Psychosis proneness and ADHD in young relatives of schizophrenia patients

Psychopathological characteristics in ultra-high risk for psychosis with and without comorbid ADHD

AIM

This study investigates the psychopathological characteristics of a sample of individuals at ultra-high risk for psychosis with and without comorbid attention-deficit hyperactivity disorder (ADHD).

METHODS

Twenty-eight subjects (aged 13-21 years; 13 females) with attenuated psychosis syndrome (APS) were recruited in a cross-sectional study and divided into two groups, each with 14 patients, according to the presence or absence of ADHD.

RESULTS

The APS group showed a significantly higher prevalence of negative symptoms than the APS + ADHD group. Other characteristics investigated (positive symptoms, aberrant salience, psychotic-like experiences and prodromal symptoms) did not differ between groups.

CONCLUSIONS

The different profiles of negative symptoms in the APS with or without ADHD might suggest the presence of a specific subtype among individuals at ultra-high risk for psychosis. Longitudinal studies with larger samples will provide information about the role of negative symptoms in determining conversion to full psychosis in those people with 'pure' APS and those with APS + ADHD.

Associations between ADHD and risk of six psychiatric disorders: a Mendelian randomization study

BACKGROUND

Observational studies and diagnostic criteria have indicated that Attention Deficit Hyperactivity Disorder (ADHD) frequently comorbid with various psychiatric disorders. Therefore, we conducted a Mendelian randomization (MR) study to explore this potential genetic association between ADHD and six psychiatric disorders.

METHODS

Using a two-sample Mendelian randomization (MR) design, this study systematically screened genetic instrumental variables (IVs) based on the genome-wide association studies (GWAS) of ADHD and six psychiatric disorders, with the inverse variance weighted (IVW) method as the primary approach.

RESULTS

The study revealed a positive and causal association between ADHD and the risk of ASD, with an odds ratio (OR) of 2.328 (95%CI: 1.241-4.368) in the IVW MR analysis. Additionally, ADHD showed a positive causal effect on an increased risk of schizophrenia, with an OR of 1.867 (95%CI: 1.260-2.767) in the IVW MR analysis. However, no causal effect of Tic disorder, Mental retardation, Mood disorders and Anxiety disorder with ADHD was found in the analysis mentioned above.

CONCLUSION

Our MR analysis provides robust evidence of the causal role of ADHD in increasing the risk of ASD and schizophrenia. However, ADHD is not associated with the risk of Tic Disorder, Mental Retardation, Mood Disorders and Anxiety Disorder. This suggests the need for increased attention to the co-occurrence of ADHD-ASD or ADHD-schizophrenia and the implementation of timely intervention and treatment.

Clinical and cognitive characteristics of subjects with schizophrenia and childhood attention-deficit/hyperactivity disorder: Results from the multicentric FACE-SZ cross-sectional dataset

BACKGROUND

Childhood Attention-deficit/hyperactivity disorder (C-ADHD) is a neurodevelopmental disorder, associated with an increased risk of subsequent schizophrenia. The objective of the present study was to determine the prevalence of C-ADHD in schizophrenia and the clinical and cognitive characteristics associated with C-ADHD history in schizophrenia.

METHODS

569 subjects with schizophrenia (74 % men, mean age 30.8) were included in ten expert centers at a national level and tested with a comprehensive battery of clinician-rated, patient-reported scales and cognitive tests. C-ADHD was assessed with the WURS (Wender Utah Rating Scale) self-report questionnaire. Multivariate, correlation, and principal component analyses (PCA) were conducted.

RESULTS

Thirty-nine subjects (N = 39, 6.9 %) were classified in the C-ADHD group. Compared to those without C-ADHD, subjects with C-ADHD were more frequently male, had lower education levels, more severe positive clinical symptoms, more subjective cognitive deficits complaints, and lower medication adherence with small to medium effect sizes. Two cognitive components emerged from the PCA, one component including perceptual reasoning and working memory, and another component including visuospatial search and graphomotor speed, cognitive inhibition/flexibility and central executive functioning. Both components were associated with lower performances in the C-ADHD group.

CONCLUSIONS

C-ADHD is frequent in schizophrenia and associated with more severe positive symptoms and impaired cognitive performances compared to those without C-ADHD. This suggests that the pathophysiological mechanisms contributing to these disorders may lead to the worsening of the cognitive functioning in patients with both disorders. C-ADHD is a relevant clinical marker to discriminate subgroups of schizophrenia with different profiles for a precision-psychiatry approach.

Mental disorders in preadolescent children at familial high-risk of schizophrenia or bipolar disorder - a four-year follow-up study: The Danish High Risk and Resilience Study, VIA 11: The Danish High Risk and Resilience Study, VIA 11

BACKGROUND

Children at familial high-risk of schizophrenia and bipolar disorder have an elevated prevalence of mental disorders but studies of children within a narrow age range are lacking and there are few conjoint studies of these two groups. Knowledge on their mental health is important for prevention and early intervention.

METHODS

The authors examined mental disorders and global functioning in children at familial high-risk of schizophrenia (FHR-SZ) and bipolar disorder (FHR-BP) compared with population-based controls. In a longitudinal cohort study, 450 children (FHR-SZ, n = 171; FHR-BP, n = 104; controls, n = 175), were assessed for Axis I disorders at baseline and four-year follow-up (mean age 11.9, SD 0.2) with the Kiddie Schedule for Affective Disorders and Schizophrenia for School-Age Children and for global functioning with Children's Global Assessment Scale.

RESULTS

Cumulative incidence of Any Axis I disorder was elevated by age 11 in children at FHR-SZ (54.4%, OR 3.0, 95% CI 1.9-4.7, p < .001) and children at FHR-BP (52.9%, OR 2.8, 95% CI 1.7-4.7, p < .001) compared with controls (28.6%). Children at FHR-SZ and FHR-BP had higher rates of affective disorders (OR 4.4, 95% CI 1.4-13.5, p = .009; OR 5.1, 95% CI 1.6-16.4, p = .007), anxiety disorders (OR 2.1, 95% CI 1.1-4.0, p = .02; OR 3.0, 95% CI 1.5-6.1, p = .002), and stress and adjustment disorders (OR 3.3, 95% CI 1.4-7.5, p = .006; OR 5.3, 95% CI 2.2-12.4, p < .001). Disruptive behavior disorders (OR 2.8, 95% CI 1.0-7.3, p = .04) and ADHD (OR 2.9, 95% CI 1.6-5.3, p < .001) were elevated in children at FHR-SZ. Both FHR groups had lower global functioning than controls. Cumulative incidence of disorders increased equally across the three groups from early childhood to preadolescence and level of functioning did not change differentially.

CONCLUSIONS

Children at FHR-SZ and FHR-BP have an elevated prevalence of mental disorders and poorer functioning than controls. Vulnerability in children at FHR manifests early and remains stable throughout childhood. Early attention toward their mental health and identification of those in need of intervention is warranted.

Altered working memory-related brain activity in children at familial high risk for psychosis: A preliminary study

BACKGROUND

Schizophrenia spectrum disorders are heritable illnesses that usually manifest in early adulthood but are increasingly viewed as neurodevelopmental disorders. Functional magnetic resonance imaging (fMRI) studies show altered brain activity during performance of working memory (WM) tasks in both individuals with schizophrenia and their first-degree relatives as compared to healthy controls (HC). This study examined whether similar changes are already present in pre-adolescent children at familial high-risk (FHR) for psychosis.

METHODS

37 children (17 FHR, 20 HC) between 7 and 12 years old participated in this study. WM performance was assessed using the Wechsler Intelligence Scale for Children-IV (WISC-IV). To assess brain activation during WM performance, participants completed a visual block-designed n-back task with 2 conditions (2-back and 0-back) during scanning. fMRI data was preprocessed and analyzed using FSL Feat.

RESULTS

Compared to HC, FHR children showed significantly lower WISC-IV WM scores. In addition, FHR children exhibited hypoactivation in the 2-back (versus 0-back) condition in a cluster encompassing bilateral precuneus and cuneus and right posterior cingulate cortex. There were no significant group-differences in n-back task performance and brain activation. The precuneus cluster was not correlated with n-back performance or WISC WM scores.

CONCLUSIONS

The current results provide preliminary evidence of impaired WM function and altered brain activity during WM performance in children with a familial predisposition for psychosis. Longitudinal studies are needed to determine whether these findings are related to abnormal brain development and predictive of cognitive deficits and psychosis later in life.

Attention-deficit/hyperactivity disorder in youth with psychosis spectrum symptoms

BACKGROUND

Childhood attention deficit-hyperactivity disorder (ADHD) is common in psychotic disorders. However, prevalence estimates vary widely and the impact of ADHD on the severity of psychotic symptoms and associated features is unclear. We used the Philadelphia Neurodevelopmental Cohort (PNC; n = 9498 youth age 8-21), which includes a comprehensive structured interview of clinical symptoms and the Penn Computerized Neurocognitive Battery (CNB), to clarify the prevalence of ADHD in psychosis spectrum (PS) youth and determine if comorbid ADHD is associated with severity of psychotic symptoms and cognitive impairment.

METHODS

Prevalence of ADHD among PS youth was established by comparing PS youth to all other youth in the PNC cohort. Cognition was compared between four groups: typically developing (TD), ADHD, PS without ADHD (PS-ADHD), and PS with ADHD (PS+ADHD). To evaluate the impact of ADHD on psychosis symptomatology, severity of positive and negative psychotic symptoms was compared between PS-ADHD and PS+ADHD groups.

RESULTS

ADHD was more prevalent in PS youth compared to non-PS youth (45% vs. 20%). Cognition was significantly impaired in PS youth compared to TD youth, but the presence of ADHD in PS youth was not associated with greater cognitive impairment. Co-morbid ADHD was, however, associated with more severe psychosis symptoms in PS youth.

CONCLUSION

ADHD is more common among PS youth compared to youth without PS symptoms and is associated with more severe psychotic symptoms, but not severity of cognitive impairment. The association between ADHD and psychotic disorders may be mediated by psychosis symptoms in youth and may manifest a more stable cognitive impairment.

[ADHD during childhood and subsequent psychotic disorder: A link?]

OBJECTIVES

Attention Deficit with/without Hyperactivity Disorder (ADHD) is a neurodevelopmental disorder with frequent comorbid psychiatric disorders. Several studies have underlined the increased risk of developing a psychotic disorder subsequent to a childhood ADHD. The aim of our review is not only to clarify this association and the related physiopathology but also to understand the consequences for therapeutic management.

METHODS

We processed a narrative review of available literature based on a research of the PubMed database. Articles related to ADHD and psychotic disorder on a genetical, clinical or biological level were selected by one of the authors.

RESULTS

ADHD and psychotic disorders share neonatal, environmental, and genetic risk factors. On a neurobiological level, both disorders are concerned by a dysfunction of the dopaminergic system with an abnormal regulation of dopaminergic neurons' phasic and tonic activity. Our review aims to explain the « dynamic » model of dopaminergic dysfunctions and propose some guidance for pharmacological treatment of ADHD, with or without psychotic disorder. This model offers a better understanding of why methylphenidate is not associated to an increased risk of psychotic disorder and could act as a protective factor. Association between ADHD and psychotic disorders could be explained by some comorbidities such as substance use disorders which are frequently associated with both conditions and could act as mediator in the genesis of psychotic disorders following ADHD during childhood. Our review also focuses on an epidemiological bias that could be found in some studies such as possible diagnostic errors, as some non-specific clinical signs could be found in both late diagnosed ADHD and in "at risk mental state" of psychosis.

CONCLUSION

ADHD and psychotic disorders share common risk factors, neurobiological pathways and clinical symptoms. Perspectives for future studies are proposed considering a dimensional aspect of psychiatric disorders using, for example, Research Domain Criteria and exploring the link between the two conditions.

Psychotic experiences in seven-year-old children with familial high risk of schizophrenia or bipolar disorder in: The Danish High Risk and Resilience Study - VIA 7; A population-based cohort study

We aimed to examine the prevalence of psychotic experiences (PEs) in children with familial high risk of schizophrenia (FHR-SZ) or bipolar disorder (FHR-BP) and, in exploratory analyses, to examine the possible associations between PEs and mental disorders as well as level of functioning. A cohort of seven-year-old children with FHR-SZ (N = 199), FHR-BP (N = 118) and controls (N = 196) was recruited through Danish nationwide registers. Lifetime PEs were assessed through interviews using the psychosis section of the 'Schedule for Affective Disorders and Schizophrenia for School-Age Children - Present and Lifetime Version' (K-SADS-PL). Lifetime DSM-IV diagnoses were ascertained through K-SADS-PL and the level of functioning of the children through 'Children's Global Assessment Scale'. Both children with FHR-SZ (OR = 2.9, 95% CI = 1.4-6.2, p = 0.005) and FHR-BP (OR = 2.9, 95% CI = 1.3-6.7, p = 0.011) had an increased risk of having experienced "severe" PEs compared with controls. In the overall cohort PEs were associated with any lifetime mental disorder, Attention-Deficit/Hyperactivity Disorder, anxiety disorders and a lower level of functioning. The findings of a higher proportion of high risk children reporting PEs could represent an early manifestation of later more severe psychopathology or simply an unspecific transitory symptom. Future follow-up studies of this cohort will explore the predictive value of the occurrence of PEs at age seven.

Hyperactivation of Posterior Default Mode Network During Self-Referential Processing in Children at Familial High-Risk for Psychosis

Patients with schizophrenia spectrum disorders show disturbances in self-referential processing and associated neural circuits including the default mode network (DMN). These disturbances may precede the onset of psychosis and may underlie early social and emotional problems. In this study, we examined self-referential processing in a group of children (7-12 years) at familial high risk (FHR) for psychosis (N = 17), compared to an age and sex-matched group of healthy control (HC) children (N = 20). The participants were presented with a list of adjectives and asked to indicate whether or not the adjectives described them (self-reference condition) and whether the adjectives described a good or bad trait (semantic condition). Three participants were excluded due to chance-level performance on the semantic task, leaving N = 15 FHR and N = 19 HC for final analysis. Functional MRI (fMRI) was used to measure brain activation during self-referential vs. semantic processing. Internalizing and externalizing problems were assessed with the Child Behavior Checklist (CBCL). Evaluating main effects of task (self > semantic) showed activation of medial prefrontal cortex in HC and precuneus/posterior cingulate cortex (PCC) in FHR. Group-comparison yielded significant results for the FHR > HC contrast, showing two clusters of hyperactivation in precuneus/ PCC (p = 0.004) and anterior cerebellum / temporo-occipital cortex (p = 0.009). Greater precuneus/PCC activation was found to correlate with greater CBCL internalizing (r = 0.60, p = 0.032) and total (r = 0.69, p = 0.009) problems. In all, this study shows hyperactivity of posterior DMN during self-referential processing in pre-adolescent FHR children. This finding posits DMN-related disturbances in self-processing as a developmental brain abnormality associated with familial risk factors that predates not just psychosis, but also the prodromal stage. Moreover, our results suggest that early disturbances in self-referential processing may be related to internalizing problems in at-risk children.

A dynamical model for the basal ganglia-thalamo-cortical oscillatory activity and its implications in Parkinson's disease

We propose to investigate brain electrophysiological alterations associated with Parkinson’s disease through a novel adaptive dynamical model of the network of the basal ganglia, the cortex and the thalamus. The model uniquely unifies the influence of dopamine in the regulation of the activity of all basal ganglia nuclei, the self-organised neuronal interdependent activity of basal ganglia-thalamo-cortical circuits and the generation of subcortical background oscillations. Variations in the amount of dopamine produced in the neurons of the substantia nigra pars compacta are key both in the onset of Parkinson’s disease and in the basal ganglia action selection. We model these dopamine-induced relationships, and Parkinsonian states are interpreted as spontaneous emergent behaviours associated with different rhythms of oscillatory activity patterns of the basal ganglia-thalamo-cortical network. These results are significant because: (1) the neural populations are built upon single-neuron models that have been robustly designed to have eletrophysiologically-realistic responses, and (2) our model distinctively links changes in the oscillatory activity in subcortical structures, dopamine levels in the basal ganglia and pathological synchronisation neuronal patterns compatible with Parkinsonian states, this still remains an open problem and is crucial to better understand the progression of the disease.

Clinical and cognitive correlates of childhood attention-deficit/hyperactivity disorder in first-episode psychosis: A controlled study

The relationship between childhood attention-deficit/hyperactivity disorder (c-ADHD) and psychosis has been understudied. Cognitive dysfunction is a core feature of both disorders, but no previous study has investigated whether first-episode psychosis (FEP) with c-ADHD (FEP-ADHD⁺) presents a different cognitive profile than FEP without c-ADHD (FEP-ADHD^-). One hundred and thirty-three FEP outpatients were screened for c-ADHD through a diagnostic interview and underwent a comprehensive clinical and cognitive assessment with the MATRICS Consensus Cognitive Battery (MCCB). Cognitive differences among FEP groups, and a group of 65 healthy controls (HCs) were analysed by multivariate analysis of covariance. Nearly 25% of FEP fulfilled criteria for c-ADHD. Both FEP groups performed worse than HCs in speed processing, executive function and social cognition, but only the FEP-ADHD⁺group was significantly more impaired than the HC group in attention (F = 4.35; p = 0.04). Only the Trail Making Test A (TMT-A) (F = 6.99; p = 0.01) within the domain of processing speed and the Neuropsychological Assessment Battery (NAB) (F = 6.46; p = 0.01) within the domain of executive function reliably differentiated the two clinical groups. The FEP groups did not differ in the severity of psychopathology, but the FEP-ADHD⁺reported fewer years of education than the FEP-ADHD^- and were more likely to use tobacco and cannabis and to require higher doses of antipsychotics to achieve a clinical response. In conclusion, we found a gradient of severity in cognitive performance between groups, with FEP-ADHD⁺ having the greatest cognitive impairment. Our results suggest that FEP-ADHD⁺ represents a subgroup with a worse prognosis than FEP-ADHD^-.

Symptomatic psychosis risk and physiological fluctuation in functional MRI data

BACKGROUND

Physiological brain pulsations have been shown to play a critical role in maintaining interstitial homeostasis in the glymphatic brain clearance mechanism. We investigated whether psychotic symptomatology is related to the physiological variation of the human brain using fMRI.

METHODS

The participants (N = 277) were from the Northern Finland Birth Cohort 1986. Psychotic symptoms were evaluated with the Positive Symptoms Scale of the Structured Interview for Prodromal Syndromes (SIPS). We used the coefficient of variation of BOLD signal (CV_BOLD) as a proxy for physiological brain pulsatility. The CV_BOLD-analyses were controlled for motion, age, sex, and educational level. The results were also compared with fMRI and voxel-based morphometry (VBM) meta-analyses of schizophrenia patients (data from the Brainmap database).

RESULTS

At the global level, participants with psychotic-like symptoms had higher CV_BOLD in cerebrospinal fluid (CSF) and white matter (WM), when compared to participants with no psychotic symptoms. Voxel-wise analyses revealed that CV_BOLD was increased, especially in periventricular white matter, basal ganglia, cerebellum and parts of the cortical structures. Those brain regions, which included alterations of physiological fluctuation in symptomatic psychosis risk, overlapped <6% with the regions that were found to be affected in the meta-analyses of previous fMRI and VBM studies in schizophrenia patients. Motion did not vary as a function of SIPS.

CONCLUSIONS

Psychotic-like symptoms were associated with elevated CV_BOLD in a variety of brain regions. The CV_BOLD findings may produce new information about cerebral physiological fluctuations that have been out of reach in previous fMRI and VBM studies.

Altered resting-state functional connectivity in young children at familial high risk for psychotic illness: A preliminary study

Multiple lines of evidence suggest that illness development in schizophrenia and other psychotic disorders predates the first psychotic episode by many years. In this study, we examined a sample of 15 pre-adolescent children, ages 7 through 12 years, who are at familial high-risk (FHR) because they have a parent or sibling with a history of schizophrenia or related psychotic disorder. Using multi-voxel pattern analysis (MVPA), a data-driven fMRI analysis, we assessed whole-brain differences in functional connectivity in the FHR sample as compared to an age- and sex-matched control (CON) group of 15 children without a family history of psychosis. MVPA analysis yielded a single cluster in right posterior superior temporal gyrus (pSTG/BA 22) showing significant group-differences in functional connectivity. Post-hoc characterization of this cluster through seed-to-voxel analysis revealed mostly reduced functional connectivity of the pSTG seed to a set of language and default mode network (DMN) associated brain regions including Heschl's gyrus, inferior temporal gyrus extending into fusiform gyrus, (para)hippocampus, thalamus, and a cerebellar cluster encompassing mainly Crus I/II. A height-threshold of whole-brain p < .001 (two-sided), and FDR-corrected cluster-threshold of p < .05 (non-parametric statistics) was used for post-hoc characterization. These findings suggest that abnormalities in functional communication in a network encompassing right STG and associated brain regions are present before adolescence in at-risk children and may be a risk marker for psychosis. Subsequent changes in this functional network across development may contribute to either disease manifestation or resilience in children with a familial vulnerability for psychosis.

The relationship of genetic susceptibilities for psychosis with physiological fluctuation in functional MRI data

Previously, schizophrenia is found to be related to the variability of the functional magnetic resonance imaging (fMRI) signal in the white matter. However, evidence about the relationship between genetic vulnerabilities and physiological fluctuation in the brain is lacking. We investigated whether familial risk for psychosis (FR) and polygenic risk score for schizophrenia (PRS) are linked with physiological fluctuation in fMRI data. We used data from the Oulu Brain and Mind study (n = 140-149, aged 20-24 years) that is a substudy of the Northern Finland Birth Cohort 1986. The participants underwent a resting-state fMRI scan. Coefficient of variation (CV) of blood oxygen level dependent (BOLD) signal (CVBOLD) was used as a proxy of physiological fluctuation in the brain. Familial risk was defined to be present if at least one parent had been diagnosed with psychosis previously. PRS was computed based on the results of the prior GWAS by the Schizophrenia Working Group. FR or PRS were not associated with CVBOLD in cerebrospinal fluid, white matter, or grey matter. The findings did not provide evidence for the previous suggestions that genetic vulnerabilities for schizophrenia become apparent in alterations of the variation of the BOLD signal in the brain.

Alterations in Task-Related Brain Activation in Children, Adolescents and Young Adults at Familial High-Risk for Schizophrenia or Bipolar Disorder - A Systematic Review

Children, adolescents, and young adults with at least one first-degree relative [familial high-risk (FHR)] with either schizophrenia (SZ) or bipolar disorder (BD) have a one-in-two risk of developing a psychiatric disorder. Here, we review functional magnetic resonance imaging (fMRI) studies which examined task-related brain activity in young individuals with FHR-SZ and FHR-BD. A systematic search identified all published task-related fMRI studies in children, adolescents, and young adults below an age of 27 years with a first-degree relative with SZ or BD, but without manifest psychotic or affective spectrum disorder themselves. The search identified 19 cross-sectional fMRI studies covering four main cognitive domains: 1) working memory (n = 3), 2) cognitive control (n = 4), 3) reward processing (n = 3), and 4) emotion processing (n = 9). Thirteen studies included FHR-BD, five studies included FHR-SZ, and one study included a pooled FHR group. In general, task performance did not differ between the respective FHR groups and healthy controls, but 18 out of the 19 fMRI studies revealed regional alterations in task-related activation. Brain regions showing group differences in peak activation were regions associated with the respective task domain and showed little overlap between FHR-SZ and FHR-BD. The low number of studies, together with the low number of subjects, and the substantial heterogeneity of employed methodological approaches within the domain of working memory, cognitive control, and reward processing impedes finite conclusions. Emotion processing was the most investigated task domain in FHR-BD. Four studies reported differences in activation of the amygdala, and two studies reported differences in activation of inferior frontal/middle gyrus. Together, these studies provide evidence for altered brain processing of emotions in children, adolescents, and young adults at FHR-BD. More studies of higher homogeneity, larger sample sizes and with a longitudinal study design are warranted to prove a shared or specific FHR-related endophenotypic brain activation in young first-degree relatives of individuals with SZ or BD, as well as to pinpoint specific alterations in brain activation during cognitive-, emotional-, and reward-related tasks.

Can neuropsychological testing facilitate differential diagnosis between at-risk mental state (ARMS) for psychosis and adult attention-deficit/hyperactivity disorder (ADHD)?

Background:

Patients with an at-risk mental state (ARMS) for psychosis and patients with attention-deficit/hyperactivity disorder (ADHD) have many overlapping signs and symptoms and hence can be difficult to differentiate clinically. The aim of this study was to investigate whether the differential diagnosis between ARMS and adult ADHD could be improved by neuropsychological testing.

Methods:

168 ARMS patients, 123 adult ADHD patients and 109 healthy controls (HC) were recruited via specialized clinics of the University of Basel Psychiatric Hospital. Sustained attention and impulsivity were tested with the Continuous Performance Test, verbal learning and memory with the California Verbal Learning Test, and problem solving abilities with the Tower of Hanoi Task. Group differences in neuropsychological performance were analyzed using generalized linear models. Furthermore, to investigate whether adult ADHD and ARMS can be correctly classified based on the pattern of cognitive deficits, machine learning (i.e. random forests) was applied.

Results:

Compared to HC, both patient groups showed deficits in attention and impulsivity and verbal learning and memory. However, in adult ADHD patients the deficits were comparatively larger. Accordingly, a machine learning model predicted group membership based on the individual neurocognitive performance profile with good accuracy (AUC = 0.82).

Conclusions:

Our results are in line with current meta-analyses reporting that impairments in the domains of attention and verbal learning are of medium effect size in adult ADHD and of small effect size in ARMS patients and suggest that measures of these domains can be exploited to improve the differential diagnosis between adult ADHD and ARMS patients.

Social skills training for attention deficit hyperactivity disorder (ADHD) in children aged 5 to 18 years

BACKGROUND

Attention deficit hyperactivity disorder (ADHD) in children is associated with hyperactivity and impulsivity, attention problems, and difficulties with social interactions. Pharmacological treatment may alleviate the symptoms of ADHD but this rarely solves difficulties with social interactions. Children with ADHD may benefit from interventions designed to improve their social skills. We examined the benefits and harms of social skills training on social skills, emotional competencies, general behaviour, ADHD symptoms, performance in school of children with ADHD, and adverse events.

OBJECTIVES

To assess the beneficial and harmful effects of social skills training in children and adolescents with ADHD.

SEARCH METHODS

In July 2018, we searched CENTRAL, MEDLINE, Embase, PsycINFO, 4 other databases and two trials registers.We also searched online conference abstracts, and contacted experts in the field for information about unpublished or ongoing randomised clinical trials. We did not limit our searches by language, year of publication, or type or status of publication, and we sought translation of the relevant sections of non-English language articles.

SELECTION CRITERIA

Randomised clinical trials investigating social skills training versus either no intervention or waiting-list control, with or without pharmacological treatment of both comparison groups of children and adolescents with ADHD.

DATA COLLECTION AND ANALYSIS

We conducted the review in accordance with the Cochrane Handbook for Systematic Reviews of Intervention. We performed the analyses using Review Manager 5 software and Trial Sequential Analysis. We assessed bias according to domains for systematic errors. We assessed the certainty of the evidence with the GRADE approach.

MAIN RESULTS

We included 25 randomised clinical trials described in 45 reports. The trials included a total of 2690 participants aged between five and 17 years. In 17 trials, participants were also diagnosed with various comorbidities.The social skills interventions were described as: 1) social skills training, 2) cognitive behavioural therapy, 3) multimodal behavioural/psychosocial therapy, 4) child life and attention skills treatment, 5) life skills training, 6) the "challenging horizon programme", 7) verbal self-instruction, 8) meta-cognitive training, 9) behavioural therapy, 10) behavioural and social skills treatment, and 11) psychosocial treatment. The control interventions were no intervention or waiting list.The duration of the interventions ranged from five weeks to two years. We considered the content of the social skills interventions to be comparable and based on a cognitive-behavioural model. Most of the trials compared child social skills training or parent training combined with medication versus medication alone. Some of the experimental interventions also included teacher consultations.More than half of the trials were at high risk of bias for generation of the allocation sequence and allocation concealment. No trial reported on blinding of participants and personnel. Most of the trials did not report on differences between groups in medication for comorbid disorders. We used all eligible trials in the meta-analyses, but downgraded the certainty of the evidence to low or very low.We found no clinically relevant treatment effect of social skills interventions on the primary outcome measures: teacher-rated social skills at end of treatment (standardised mean difference (SMD) 0.11, 95% confidence interval (CI) 0.00 to 0.22; 11 trials, 1271 participants; I2 = 0%; P = 0.05); teacher-rated emotional competencies at end of treatment (SMD -0.02, 95% CI -0.72 to 0.68; two trials, 129 participants; I2 = 74%; P = 0.96); or on teacher-rated general behaviour (SMD -0.06 (negative value better), 95% CI -0.19 to 0.06; eight trials, 1002 participants; I2 = 0%; P = 0.33). The effect on the primary outcome, teacher-rated social skills at end of treatment, corresponds to a MD of 1.22 points on the social skills rating system (SSRS) scale (95% CI 0.09 to 2.36). The minimal clinical relevant difference (10%) on the SSRS is 10.0 points (range 0 to 102 points on SSRS).We found evidence in favour of social skills training on teacher-rated core ADHD symptoms at end of treatment for all eligible trials (SMD -0.26, 95% CI -0.47 to -0.05; 14 trials, 1379 participants; I2= 69%; P = 0.02), but the finding is questionable due to lack of support from sensitivity analyses, high risk of bias, lack of clinical significance, high heterogeneity, and low certainty.The studies did not report any serious or non-serious adverse events.

AUTHORS' CONCLUSIONS

The review suggests that there is little evidence to support or refute social skills training for children and adolescents with ADHD. We may need more trials that are at low risk of bias and a sufficient number of participants to determine the efficacy of social skills training versus no training for ADHD. The evidence base regarding adolescents is especially weak.

Young spontaneously hypertensive rats (SHRs) display prodromal schizophrenia-like behavioral abnormalities

The Spontaneously Hypertensive Rat (SHR) strain has been suggested as an animal model of schizophrenia, considering that adult SHRs display behavioral abnormalities that mimic the cognitive, psychotic and negative symptoms of the disease and are characteristic of its animal models. SHRs display: (I) deficits in fear conditioning and latent inhibition (modeling cognitive impairments), (II) deficit in prepulse inhibition of startle reflex (reflecting a deficit in sensorimotor gating, and associated with psychotic symptoms), (III) diminished social behavior (modeling negative symptoms) and (IV) hyperlocomotion (modeling the hyperactivity of the dopaminergic mesolimbic system/ psychotic symptoms). These behavioral abnormalities are reversed specifically by the administration of antipsychotic drugs. Here, we performed a behavioral characterization of young (27-50 days old) SHRs in order to investigate potential early behavioral abnormalities resembling the prodromal phase of schizophrenia. When compared to Wistar rats, young SHRs did not display hyperlocomotion or PPI deficit, but exhibited diminished social interaction and impaired fear conditioning and latent inhibition. These findings are in accordance with the clinical course of schizophrenia: manifestation of social and cognitive impairments and absence of full-blown psychotic symptoms in the prodromal phase. The present data reinforce the SHR strain as a model of schizophrenia, expanding its validity to the prodromal phase of the disorder.

Prevalence of attention deficit hyperactivity disorder symptoms in patients with schizophrenia

OBJECTIVE

To investigate the frequency of childhood and adult attention deficit hyperactivity disorder (ADHD) symptoms in a cohort of patients with schizophrenia (SCZ).

METHODS

A systematic review was conducted to evaluate existing evidence. Two self-report questionnaires were used to investigate adult ADHD and childhood ADHD symptoms in 126 patients with ICD-10 diagnoses of SCZ.

RESULTS

Five studies were included in the systematic review, with the prevalence of childhood and adult ADHD in SCZ subjects ranging between 17-57% and 10-47% respectively. Within our cohort, 47% of patients reported positive screening for ADHD symptoms either in childhood or adulthood. 23% reported symptomatology consistent with both childhood and adult ADHD.

CONCLUSIONS

We demonstrate a greater presence of ADHD symptomatology in SCZ compared to that reported for ADHD in the general population. Our findings highlight the importance of improved clinical assessment and treatment considerations in a subgroup of patients with SCZ.

Cannabidiol Administered During Peri-Adolescence Prevents Behavioral Abnormalities in an Animal Model of Schizophrenia

Schizophrenia is considered a debilitating neurodevelopmental psychiatric disorder and its pharmacotherapy remains problematic without recent major advances. The development of interventions able to prevent the emergence of schizophrenia would therefore represent an enormous progress. Here, we investigated whether treatment with cannabidiol (CBD - a compound of Cannabis sativa that presents an antipsychotic profile in animals and humans) during peri-adolescence would prevent schizophrenia-like behavioral abnormalities in an animal model of schizophrenia: the spontaneously hypertensive rat (SHR) strain. Wistar rats and SHRs were treated with vehicle or CBD from 30 to 60 post-natal days. In experiment 1, schizophrenia-like behaviors (locomotor activity, social interaction, prepulse inhibition of startle and contextual fear conditioning) were assessed on post-natal day 90. Side effects commonly associated with antipsychotic treatment were also evaluated: body weight gain and catalepsy throughout the treatment, and oral dyskinesia 48 h after treatment interruption and on post-natal day 90. In experiment 2, serum levels of triglycerides and glycemia were assessed on post-natal day 61. In experiment 3, levels of BDNF, monoamines, and their metabolites were evaluated on post-natal days 61 and 90 in the prefrontal cortex and striatum. Treatment with CBD prevented the emergence of SHRs' hyperlocomotor activity (a model for the positive symptoms of schizophrenia) and deficits in prepulse inhibition of startle and contextual fear conditioning (cognitive impairments). CBD did not induce any of the potential motor or metabolic side effects evaluated. Treatment with CBD increased the prefrontal cortex 5-HIAA/serotonin ratio and the levels of 5-HIAA on post-natal days 61 and 90, respectively. Our data provide pre-clinical evidence for a safe and beneficial effect of peripubertal and treatment with CBD on preventing positive and cognitive symptoms of schizophrenia, and suggest the involvement of the serotoninergic system on this effect.

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.

Psychopathology in 7-year-old children with familial high risk of developing schizophrenia spectrum psychosis or bipolar disorder - The Danish High Risk and Resilience Study - VIA 7, a population-based cohort study

This study aimed to compare the psychopathological profiles of children at familial high risk of schizophrenia spectrum psychosis (FHR-SZ) or bipolar disorder (FHR-BP) with population-based controls. We used Danish nationwide registers to retrieve a cohort of 522 seven-year-old children of parents with schizophrenia spectrum psychosis (N=202), bipolar disorder (N=120) or none of these disorders (N=200). Psychopathology was assessed by reports from multiple informants, including children, parents and teachers. Lifetime DSM-IV diagnoses were ascertained by blinded raters through the Schedule for Affective Disorders and Schizophrenia for School-Age Children. The dimensional assessment of psychopathology was performed by the Child Behavior Checklist, the Teacher's Report Form, a modified version of the ADHD-Rating Scale, the Test Observation Form, and the State-Trait Anxiety Inventory for Children. Current level of functioning was evaluated using the Children's Global Assessment Scale (CGAS). The prevalence of lifetime psychiatric diagnoses was significantly higher in both FHR-SZ children (38.7%, odds ratio, OR=3.5, 95% confidence interval, CI: 2.2-5.7, p < 0.001) and FHR-BP children (35.6%, OR=3.1, 95% CI: 1.8-5.3, p < 0.001) compared with controls (15.2%). FHR-SZ children displayed significantly more dimensional psychopathology on all scales and subscales compared with controls except for the Anxious subscale of the Test Observation Form. FHR-BP children showed higher levels of dimensional psychopathology on several scales and subscales compared with controls, but lower levels compared with FHR-SZ children. Level of functioning was lower in both FHR-SZ children (CGAS mean score = 68.2; 95% CI: 66.3-70.2, p < 0.0001) and FHR-BP children (73.7; 95% CI: 71.2-76.3, p < 0.05) compared with controls (77.9; 95% CI: 75.9-79.9). In conclusion, already at the age of seven, FHR-SZ and FHR-BP children show a higher prevalence of a broad spectrum of categorical and dimensional psychopathology compared with controls. These results emphasize the need for developing early intervention strategies towards this vulnerable group of children.

Overlapping and disease specific trait, response, and reflection impulsivity in adolescents with first-episode schizophrenia spectrum disorders or attention-deficit/hyperactivity disorder

BACKGROUND

Schizophrenia and attention-deficit/hyperactivity disorder (ADHD) are developmental disorders with shared clinical characteristics such as cognitive impairments and impulsivity. Impulsivity is a core feature of ADHD and an important factor in aggression, violence, and substance use in schizophrenia. Based on the hypothesis that schizophrenia and ADHD represent a continuum of neurodevelopmental impairments, the aim was to identify overlapping and disease specific forms of impulsivity.

METHODS

Adolescents between 12 and 17 years of age were assessed with the Schedule for Affective Disorders and Schizophrenia for School-aged Children - Present and Lifetime Version. Subjects with early-onset, first-episode schizophrenia spectrum disorders (EOS) (N = 29) or ADHD (N = 29) and healthy controls (N = 45) were compared on two performance measures (Information Sampling Task, Stop Signal Task) and a subjective personality trait measure of impulsivity (Barratt Impulsiveness Scale, Version 11 (BIS-11)).

RESULTS

Significantly increased reflection impulsivity was observed in ADHD but not in the EOS group. No significant response inhibition deficits (stop signal reaction time) were found in the two clinical groups. The ADHD and the EOS group showed significantly increased motor, attentional, and non-planning subtraits of impulsivity.

CONCLUSIONS

Impaired pre-decisional information gathering appeared to be specific for ADHD while the information gathering was not significantly reduced in subjects with EOS. Neither the ADHD nor EOS group showed impaired response inhibition but shared increased personality subtraits of attentional, non-planning, and motor impulsivity although the latter was significantly more pronounced in ADHD. These increased subtraits of impulsivity may reflect diagnostic non-specific neurodevelopmental impairments in ADHD and EOS in adolescence.

Delusion-proneness displays comorbidity with traits of autistic-spectrum disorders and ADHD

There is an increasing body of evidence suggesting a significant comorbidity between psychotic disorders such as schizophrenia and attention-deficit/hyperactivity disorder (ADHD) or autism-spectrum disorders (ASD). Recently, research on psychosis-proneness in otherwise healthy individuals has been a promising way to better understand the mechanisms underlying psychosis. As both ADHD and ASD symptoms show a normal distribution in the general population, such trait comorbidity may confound studies on psychosis-proneness. Thus, understanding the extent to which psychosis-proneness relates to ADHD and ASD symptoms in healthy subjects is crucial for studies focusing on at-risk or psychosis-prone populations. In the present paper we tested the robustness of overlap between psychosis-proneness and ADHD/ASD symptoms, by studying correlations between the scores of three commonly-used questionnaires assessing delusion-proneness (Peters’ Delusion Inventory), ADHD tendencies (Adult ADHD Self-Report Scale) and ASD tendencies (Autism Quotient), on a large sample of healthy individuals (n = 925) using raw scores, prototypical questions and a factor analysis. The results showed consistently positive correlations between psychosis-proneness and ADHD-, as well as ASD-symptoms. While the effect was weak for ASD, it was moderate for ADHD. The findings support the idea that when investigating psychosis-proneness it is crucial to also take ADHD- and ASD-tendencies into account, in order to conclude that the reported results in a given study are specific to psychosis-proneness. The observed trait correlations also suggest a common pathway in the underlying information processing of these states.

Symptom Overlap and Screening for Symptoms of Attention-Deficit/Hyperactivity Disorder and Psychosis Risk in Help-Seeking Psychiatric Patients

Symptoms of attention-deficit/hyperactivity disorder (ADHD) and psychosis risk share features which might represent an early vulnerability marker for schizophrenia. Early detection of individuals with this symptomatic overlap is relevant and may assist clinicians in their decision making for diagnosis and treatment. This study sought to analyze the capability of different instruments in the screening of patients for ADHD symptoms or at psychosis risk, assess their classification accuracy, and describe the extent of symptoms overlap between them. 243 adult patients completed one instrument screening for ADHD and two instruments screening for psychosis risk symptoms [Adult ADHD Self-Report Scale Symptom Checklist (ASRS-v1.1); Prodromal Questionnaire Brief Version (PQ-16); Self-Screen Prodrome (SPro)]. The ability of these instruments to distinguish between the symptomaticity of these patients appears modest. The most satisfactory scale to identify subjects at psychosis risk was SPro with its subscale psychosis risk. ASRS-v1.1 showed good reliability in assessing individuals as not having ADHD symptoms and had higher probability to achieve its own and the cut-off of another questionnaire. Subjects having symptoms of psychosis risk and ADHD showed elevated symptomatology. Reliable instruments capable of separating ADHD symptoms from those of psychosis risk are needed to better identify the symptomatic overlap of this two conditions.

Psychiatric disorders in child and adolescent offspring of patients with schizophrenia and bipolar disorder: A controlled study

BACKGROUND

Early clinical manifestations predating schizophrenia (SZ) and bipolar disorder (BP) have not been fully characterized. Child offspring studies are a valuable opportunity to study the natural history of the illness from its earliest stages. However, there is limited evidence assessing young offspring of SZ and BP simultaneously. We set out to assess rates of psychiatric disorders in child and adolescent offspring of SZ and BP, relative to offspring of community controls, so as to characterize the early phenotype of the disorders comparatively.

METHODS

SZ and BP parents with offspring aged 7-17years were recruited through adult mental health services of two tertiary hospitals. Community control (CC) parents were recruited from the same geographical area. Ninety BP-offspring, 41 SZ-offspring and 107 CC-offspring were assessed using the K-SADS-PL by child psychiatrists blinded to parental status. Differences in prevalence of psychiatric disorders between groups were adjusted for confounders and for sibling correlation using generalised estimating equations.

RESULTS

We found a gradient of clinical severity and social disadvantage between SZ, BP and CC-offspring. After adjusting for socio-demographic confounders, SZ and BP-offspring presented higher rates of attention deficit hyperactivity disorder (ADHD) than CC-offspring. ADHD was more prevalent in SZ-offspring than BP-offspring, and BP-offspring presented a higher prevalence of depression than CC-offspring.

CONCLUSIONS

The higher rates of ADHD in SZ-offspring suggest that abnormal neurodevelopmental processes may exert a stronger influence in SZ than BP. Follow-up of these children will help elucidate the role of ADHD and depression phenotypes in predicting future transition to SZ or BP.

Adult attention deficit hyperactivity symptoms and psychosis: Epidemiological evidence from a population survey in England

Despite both having some shared features, evidence linking psychosis and adult attention deficit hyperactivity disorder (ADHD) is sparse and inconsistent. Hypotheses tested were (1) adult ADHD symptoms are associated with auditory hallucinations, paranoid ideation and psychosis (2) links between ADHD symptoms and psychosis are mediated by prescribed ADHD medications, use of illicit drugs, and dysphoric mood. The Adult Psychiatric Morbidity Survey 2007 (N=7403) provided data for regression and multiple mediation analyses. ADHD symptoms were coded from the ADHD Self-Report Scale (ASRS). Higher ASRS total score was significantly associated with psychosis, paranoid ideation and auditory hallucinations despite controlling for socio-demographic variables, verbal IQ, autism spectrum disorder traits, childhood conduct problems, hypomanic and dysphoric mood. An ASRS score indicating probable ADHD diagnosis was also significantly associated with psychosis. The link between higher ADHD symptoms and psychosis, paranoia and auditory hallucinations was significantly mediated by dysphoric mood, but not by use of amphetamine, cocaine or cannabis. In conclusion, higher levels of adult ADHD symptoms and psychosis are linked and dysphoric mood may form part of the mechanism. Our analyses contradict the traditional clinical view that the main explanation for people with ADHD symptoms developing psychosis is illicit drugs.

Demographic and Environmental Factors Associated With Successful Day School Treatment Program Outcomes

In this study the authors examine the impact of admission characteristics of 105 students admitted to a day school treatment program on outcomes. Those who graduated, earned a general education diploma (GED), or were returned to a regular classroom setting were categorized as successful and those placed in a more restrictive settings (including detention), dropped out, or left the program with no known outcome were unsuccessful. The sample was largely male (n = 78, 74.3%), Caucasian (64%, n = 67), poor (53.4%), and entered in middle school or high school (73%). The majority (53.3%) had 4 or more prior educational placements before entering. They stayed in the program on average 2.5 years (SD = 2.17) with a range from 6 days through 10 years. Forty-three (41%) students were successfully discharged. Unsuccessfully discharged students dropped out (31.4%), placed in residential programs (19%), or were psychiatrically hospitalized (5.7%). At intake, 56 (53.3%) had a history of truancy, 38 (37.1%) had a PINS and 28 (26.7%) had been on probation. African Americans were approximately 73% less likely to succeed and were more likely to be from families meeting federal poverty guidelines and to live in single family households. Those who entered the program in grades K-6 or 10-12 were over 3 times more likely to succeed than students admitted in grades 7-9. Using logistic regression to assess the bivariate relationships of the demographic characteristics with successful discharge, race, admission while in grades 7-9, having both parents at home, and number of days in the program were significantly associated with success. Having externalizing behaviors, 5 or more prior placements, history of truancy, and contact with the juvenile justice system were associated with unsuccessful outcomes. Students with a history of being in the juvenile justice system were 87% less likely to succeed in the program. Implications for school social workers are discussed.

Application of proteomics in diagnosis of ADHD, schizophrenia, major depression, and suicidal behavior

This report focuses on the application of different proteomic techniques in diagnosis and treatment of psychiatric disorders such as major depression, suicidal behavior, schizophrenia, and attention deficit/hyperactivity disorder (ADHD). Firstly, we briefly describe different analytic approaches that can be applied for the discovery of specific biomarkers for diagnosing the above disorders, as well as for monitoring the effect of their treatment. Secondly, we discussed the types of biomarkers in general used in biomedicine for characterizing different disorders and diseases. Next, the potential applications of these biomarkers for diagnosing and managing major depression, suicidal behavior, schizophrenia, and ADHD are discussed in details. Forensic aspects of these biomarkers for the above disorders are also considered. Finally, we discuss the potential of specific biomarkers for distinguishing between comorbid psychiatric disorders in clinical setup as well as their potential for understanding mechanisms underlying the disorders and in discovery of new treatment strategies.

ADHD and nicotine use in schizophrenia or Asperger syndrome: a controlled study

OBJECTIVE

To examine ADHD prevalence, rating scales, and relationship to nicotine use in adults with schizophrenia or Asperger syndrome.

METHOD

Ninety-five individuals, 41 with schizophrenia and 54 with Asperger syndrome, were included. Self-rating of adult ADHD symptoms with the Wender-Reimherr Adult Attention Deficit Diagnostic Rating Scale (WRAADDS), parent rating of proband's ADHD childhood and adult life symptoms using the Swanson, Nolan, and Pelham Questionnaire (SNAP), and report of clinical ADHD diagnosis were included as ADHD measures. Nicotine use data were compared with data from a population sample.

RESULTS

In all, 10% of the schizophrenia group and 30% of the Asperger syndrome group had a clinical ADHD diagnosis. Nicotine dependency in the whole sample was closely linked to ADHD.

CONCLUSION

The prevalence of comorbid ADHD was high in schizophrenia and Asperger syndrome. The WRAADDS self-rating scale for ADHD can be one useful tool for assessing comorbid ADHD in these patient groups.

Genetic variation associated with euphorigenic effects of d-amphetamine is associated with diminished risk for schizophrenia and attention deficit hyperactivity disorder

Here, we extended our findings from a genome-wide association study of the euphoric response to d-amphetamine in healthy human volunteers by identifying enrichment between SNPs associated with response to d-amphetamine and SNPs associated with psychiatric disorders. We found that SNPs nominally associated (P ≤ 0.05 and P ≤ 0.01) with schizophrenia and attention deficit hyperactivity disorder were also nominally associated with d-amphetamine response. Furthermore, we found that the source of this enrichment was an excess of alleles that increased sensitivity to the euphoric effects of d-amphetamine and decreased susceptibility to schizophrenia and attention deficit hyperactivity disorder. In contrast, three negative control phenotypes (height, inflammatory bowel disease, and Parkinson disease) did not show this enrichment. Taken together, our results suggest that alleles identified using an acute challenge with a dopaminergic drug in healthy individuals can be used to identify alleles that confer risk for psychiatric disorders commonly treated with dopaminergic agonists and antagonists. More importantly, our results show the use of the enrichment approach as an alternative to stringent standards for genome-wide significance and suggest a relatively novel approach to the analysis of small cohorts in which intermediate phenotypes have been measured.

Development of schizotypal symptoms following psychiatric disorders in childhood or adolescence

It was examined how juvenile psychiatric disorders and adult schizotypal symptoms are associated. 731 patients of the Department of Child and Adolescent Psychiatry of the University Medical Centre Utrecht, the Netherlands, with mean age of 12.1 years (SD = 4.0) were reassessed at the mean age of 27.9 years (SD = 5.7) for adult schizotypal symptoms using the Schizotypal Personality Questionnaire-Revised (Vollema, Schizophr Bull 26(3):565-575, 2000). Differences between 13 juvenile DSM categories and normal controls (n = 80) on adult schizotypal total and factor scores were analyzed, using (M)ANCOVA. Pervasive developmental disorders (PDD), attention deficit hyperactivity disorders (ADHD), deferred diagnosis, sexual and gender identity disorders and depressive disorders had higher SPQ total scores when compared to normal controls (p < 0.001). Higher levels of disorganized schizotypal symptoms were found for PDD, ADHD, and deferred diagnosis (p < 0.001). The same diagnostic groups showed higher level of negative schizotypal symptoms, which was likewise true for sexual and gender identity disorders, depressive disorders, disruptive disorders, and the category of 'Other conditions that may be a focus of clinical attention' (p < 0.001). No differences with normal controls were found for adult positive schizotypal symptoms (p < 0.110). The current findings are suggestive of the idea that psychiatric disorders in childhood or adolescence are a more general expression of a liability to schizophrenia spectrum pathology in future life. In addition, specific patterns of adult schizotypal symptomatology are associated with different types of juvenile psychiatric disorder.

Shared polygenic contribution between childhood attention-deficit hyperactivity disorder and adult schizophrenia

BACKGROUND

There is recent evidence of some degree of shared genetic susceptibility between adult schizophrenia and childhood attention-deficit hyperactivity disorder (ADHD) for rare chromosomal variants.

AIMS

To determine whether there is overlap between common alleles conferring risk of schizophrenia in adults with those that do so for ADHD in children.

METHOD

We used recently published Psychiatric Genome-wide Association Study (GWAS) Consortium (PGC) adult schizophrenia data to define alleles over-represented in people with schizophrenia and tested whether those alleles were more common in 727 children with ADHD than in 2067 controls.

RESULTS

Schizophrenia risk alleles discriminated ADHD cases from controls (P = 1.04 × 10(-4), R(2) = 0.45%); stronger discrimination was given by alleles that were risk alleles for both adult schizophrenia and adult bipolar disorder (also derived from a PGC data-set) (P = 9.98 × 10(-6), R(2) = 0.59%).

CONCLUSIONS

This increasing evidence for a small, but significant, shared genetic susceptibility between adult schizophrenia and childhood ADHD highlights the importance of research work across traditional diagnostic boundaries.

Risk of bipolar disorder and schizophrenia in relatives of people with attention-deficit hyperactivity disorder

BACKGROUND

Attention-deficit hyperactivity disorder (ADHD) is associated with bipolar disorder and schizophrenia, and it has been suggested that combined bipolar disorder and ADHD is aetiologically distinct from the pure disorders.

AIMS

To clarify whether ADHD shares genetic and environmental factors with bipolar disorder and schizophrenia.

METHOD

By linking longitudinal Swedish national registers, we identified 61 187 persons with ADHD (the proband group) and their first- and second-degree relatives, and matched them with a control group of people without ADHD and their corresponding relatives. Conditional logistic regression was used to determine the risks of bipolar disorder and schizophrenia in the relatives of the two groups.

RESULTS

First-degree relatives of the ADHD proband group were at increased risk of both bipolar disorder (odds ratio (OR) = 1.84-2.54 for parents, offspring and full siblings) and schizophrenia (OR = 1.71-2.22 for parents, offspring and full siblings). The risks of bipolar disorder and schizophrenia among second-degree relatives were substantially lower than among full siblings.

CONCLUSIONS

These findings suggest that the co-occurrence of ADHD and bipolar disorder as well as ADHD and schizophrenia is due to shared genetic factors, rather than representing completely aetiologically distinct subsyndromes.

Altered fronto-limbic activity in children and adolescents with familial high risk for schizophrenia

Early symptoms of schizophrenia tend to emerge during adolescence, hich is a critical period for development of executive and emotional processing. While individuals with familial high risk (FHR) for schizophrenia may show cognitive and emotional changes, the neural mechanisms underlying the development of these changes remain unclear. The goal of this study was to identify functional differences in fronto-striato-limbic regions in children with FHR. Functional magnetic resonance imaging (MRI) data were collected from 21 children with a first-degree family member with schizophrenia and 21 controls without FHR. Participants performed an emotional oddball task requiring both selective attention and suppression of task-irrelevant emotional information. During selective attention, the group with FHR showed enhanced activation in the inferior frontal gyrus and caudate, with decreases in middle frontal gyrus and insular activation. The FHR group also showed greater age-related recruitment of anterior cingulate, temporal and occipital cortical areas during selective attention. During emotional processing, the FHR group showed decreased anterior cingulate activation, with decreased age-related recruitment of inferior frontal, parietal and occipital areas. The results suggest that FHR for schizophrenia may be associated with abnormal hyperactivation and hypoactivation of the neural circuitry engaged during executive and emotional processing and with age-related changes in neural recruitment during adolescence.

Deciphering the role of docosahexaenoic acid in brain maturation and pathology with magnetic resonance imaging

Animal studies have found that deficits in brain docosahexaenoic acid (DHA, 22:6n-3) accrual during perinatal development leads to transient and enduring abnormalities in brain development and function. Determining the relevance of this evidence to brain disorders in humans has been hampered by an inability to determine antimortem brain DHA levels and limitations associated with a postmortem approach. Accordingly, there is a need for alternate or complementary approaches to better understand the role of DHA in cortical function and pathology, and conventional magnetic resonance imaging (MRI) techniques may be ideally suited for this application. A major advantage of neuroimaging is that it permits prospective evaluation of the effects of manipulating DHA status on both clinical and neuroimaging variables. Emerging evidence from MRI studies suggest that greater DHA status is associated with cortical structural and functional integrity, and suggest that reduced DHA status and abnormalities in cortical function observed in psychiatric disorders may be interrelated phenomenon. Preliminary evidence from animal MRI studies support a critical role of DHA in normal brain development. Neuroimaging research in both human and animals therefore holds tremendous promise for developing a better understanding of the role of DHA status in cortical function, as well as for elucidating the impact of DHA deficiency on neuropathological processes implicated in the etiology and progression of neurodevelopmental and psychiatric disorders.

Neurobehavioral assessment in forensic practice

There is a growing awareness among mental health practitioners that many mental disorders previously believed to be primarily behavioral in nature, reflecting character and environment, are actually grounded in brain mal-development or brain disorder. This growing awareness, influenced by the advent of new diagnostic procedures and measures, is also found among forensic practitioners. In this paper, we describe some of the elements involved in conducting a neurobehavioral assessment of cognitive functioning, particularly in capital cases, organizing this material in terms of the professional disciplines - social work, mitigation investigation, psychological, and medical - with which these methods are mainly identified. The paper concludes with a brief discussion of how to integrate the multiple areas of expertise to create an accurate understanding of the neurobehavioral functioning and capacity of the subject. This is the basis from which civil and criminal forensic opinions must emanate.

Comparison between young siblings and offspring of subjects with schizophrenia: clinical and neuropsychological characteristics

INTRODUCTION

High rates of psychopathology and worse performance in cognitive areas have been described in high risk (HR) first degree relatives of subjects with schizophrenia. The present study aimed to examine clinical and neuropsychological characteristics in two different groups of first degree relatives of patients with schizophrenia - one of siblings (HRs), and one of offspring (HRo) - and compare them with healthy controls (HC).

METHODS

Participants were 30 HRo, 26 HRs and 33 HC, all aged between 7 and 16 years. Clinical and neuropsychological assessments were completed by all participants.

RESULTS

No significant differences were observed between HR groups in DSM-IV diagnoses. The most prevalent diagnosis in both HR samples was attention deficit/hyperactivity disorder (ADHD) followed by oppositional defiant disorder and generalized anxiety disorder. Both HR groups obtained worse scores than HC on prodromal symptoms, premorbid adjustment and behavioral problem scales. In cognitive areas, HRo performed worse than HC on most WISC-IV index scores, logical memory, visual memory and perceptual organization, whereas HRs only performed worse in WISC-IV indexes, logical memory and perceptual organization. Most of these differences remained stable after controlling for ADHD. The comparison between HRo and HRs showed significant differences in prodromal symptoms and working memory after controlling for ADHD.

CONCLUSION

Similar abnormalities in HRo and HRs were found in relation to clinical and neuropsychological variables. Subtle differences were found between HR groups with HRo showing difficulties in more clinical and neuropsychological areas than HRs and HC. This suggests that, the specific kind of family relationship should to be taken into account in future HR research.

Comorbidity of schizophrenia and adult attention-deficit hyperactivity disorder

OBJECTIVES

Adult ADHD is characterised by a plethora of comorbid conditions. However, the comorbidity of schizophrenia and ADHD does not seem to be a typical feature and is therefore under-researched.

OBJECTIVE

To identify adult patients with schizophrenia and comorbid ADHD and compare their symptomatology with schizophrenic patients without ADHD.

METHOD

Performance in specific neuropsychological tests (set shifting, selective and sustained attention, cognitive performance, and speed of information processing) was determined. Additionally, important demographic data and information about the patients' history such as the number of suicide attempts were gathered. Twenty-seven patients were involved in this study (14 male and 13 female). Fifteen patients were diagnosed with schizophrenia/no ADHD and twelve had both schizophrenia/ADHD.

RESULTS

We report here an increase in suicidal behaviour of patients with both schizophrenia and ADHD compared to schizophrenia only. A significant underperformance of the patients with ADHD comorbidity compared to patients with schizophrenia only was also determined.

CONCLUSIONS

The increased suicidal behaviour in patients with schizophrenia and ADHD suggests the need of further studies on mood regulation and suicidal ideations in these patients.

Risk factors at the low end of the psychosis continuum: much the same as at the upper end?

We investigated risk factors for subclinical symptoms of psychosis, and focused on two psychosis dimensions previously identified in the Zurich Study, namely "schizophrenia nuclear symptoms" and "schizotypal signs". We examined the data from 9814 Swiss conscripts from 2003. The psychosis symptom dimensions were derived from the Symptom-Checklist-90-R (SCL-90-R), and were regressed on a broad range of known risk factors for psychosis. Risk factors typically assigned to schizophrenia and other psychotic disorders - cannabis use, childhood adversity, reading and writing difficulties, attention deficit hyperactivity disorder (ADHD), psychiatric disorders and addiction in parents and the extended family - are relevant also at subclinical levels. Our analyses suggested that specific risk factors may be assigned to distinct psychosis dimensions, as previously determined in an analysis from the Zurich Study. If there are different pathways to psychosis characterized by specific symptom dimensions and risk factors, they mostly co-exist and interact at different symptom load levels.

Effects of antipsychotics and amphetamine on social behaviors in spontaneously hypertensive rats

We have recently reported that spontaneously hypertensive rats (SHRs) exhibit a deficit in contextual fear conditioning that is specifically reversed by antipsychotic and potentiated by psychostimulants and other manipulations thought to produce schizophrenia-like states in rodents. Based on these findings, we suggested that this deficit in fear conditioning could be used as an experimental model of emotional processing impairments observed in schizophrenia. This strain has also been suggested as a model by which to study attention deficit/hyperactivity disorder (ADHD). Considering that schizophrenia and ADHD are both characterized by poor social function, this study aimed to investigate possible behavioral deficits of SHRs in a social context. Furthermore, we sought to examine the effects of typical and atypical antipsychotics (used for the treatment of schizophrenia) and a psychostimulant (used to treat ADHD) on these behaviors. Pairs of unfamiliar rats of the same or different (i.e., Wistar) strains were treated with one of the aforementioned drugs and placed in an open-field for 10min. During this time, social behaviors, locomotion and rearing frequencies were scored. Atypical antipsychotics increased social interaction in Wistar rats (WRs) and improved the deficit in social interaction exhibited by SHRs. In addition, the SHR group displayed hyperlocomotion that was attenuated by all antipsychotics (quetiapine and clozapine also decreased locomotion in WRs) and potentiated by amphetamine (which also increased locomotion in WRs). Our results reveal that the behavioral profile of the SHR group demonstrates that this strain can be a useful animal model to study several aspects of schizophrenia.

The meaning of childhood attention-deficit hyperactivity symptoms in patients with a first-episode of schizophrenia-spectrum psychosis

OBJECTIVE

To examine childhood ADHD symptoms in regard to their association with a number of illness-related variables including risk factors, early neurodevelopment, premorbid functioning and clinical characteristics in patients with schizophrenia-spectrum psychoses.

METHODS

One-hundred and twenty-two first-episode patients with DSM-IV schizophrenia-spectrum disorders were retrospectively assessed by means of their biological mothers for childhood ADHD symptoms. Using correlational analyses and hierarchical regression models, the severity of ADHD symptoms was examined in relation to familial liability to schizophrenia, obstetric complications, milestones attainment delay, premorbid functioning during childhood and adolescence, age at illness onset, episode psychopathology and response to treatment after one-month trial with antipsychotic medication.

RESULTS

Twenty-one patients (17%) met DSM-IV criteria for childhood ADHD. Univariate analyses showed that severity of childhood ADHD symptoms was related to male gender, obstetric complications, delayed milestones attainment, poor school functioning and an earlier age of onset of psychotic symptoms. Hierarchical regression analyses showed that severity of childhood ADHD symptoms was independently predicted by obstetric complications and neurodevelopmental delay, with no further variables entering in the regression models. Path analyses showed that obstetric complications had both direct and indirect effects, through neurodevelopmental delay, on ADHD symptoms.

CONCLUSIONS

These findings are consistent with a neurodevelopmental model of schizophrenia and with the hypothesis of shared environmental risk factors between ADHD and schizophrenia-spectrum disorders. Childhood ADHD symptoms in schizophrenia-spectrum disorders appear to be an epiphenomenon of obstetric complications and early neurodevelopment delay with no further influence on the clinical expression of the illness.

Associations between psychotic-like symptoms and inattention/hyperactivity symptoms

OBJECTIVE

Our aim was to study the association between psychotic-like symptoms and inattention/hyperactivity symptoms in a general adolescent population.

SUBJECTS AND METHODS

The sample is based on a population-based prospective mother-child birth cohort, the Northern Finland Birth Cohort 1986. In the 15-16-year follow-up survey, the adolescents completed the Youth Self-Report questionnaire as well as the PROD-Screen questionnaire that addressed prodromal symptoms of psychosis. Meanwhile, their parents assessed inattention and hyperactive symptoms of their offspring by completing the Strengths and Weaknesses of ADHD Symptoms and Normal Behaviors questionnaire (N = 5,318). The cross-sectional associations between psychotic-like symptoms and inattention/hyperactivity symptoms were studied with logistic regression models.

RESULTS

The association between negative psychotic-like symptoms and inattention symptoms, especially the dreamy type of inattention symptoms (e.g., difficulties in organizing tasks, losing things, being forgetful), was statistically significant for both genders. Psychotic-like symptoms, however, were not associated with hyperactivity symptoms.

CONCLUSIONS

The present findings demonstrate that an association between psychotic-like symptoms and attentional dysfunction, which has been found in clinical samples, is also present in a general adolescent population.

Copy number variations of chromosome 16p13.1 region associated with schizophrenia

Deletions and reciprocal duplications of the chromosome 16p13.1 region have recently been reported in several cases of autism and mental retardation (MR). As genomic copy number variants found in these two disorders may also associate with schizophrenia, we examined 4345 schizophrenia patients and 35,079 controls from 8 European populations for duplications and deletions at the 16p13.1 locus, using microarray data. We found a threefold excess of duplications and deletions in schizophrenia cases compared with controls, with duplications present in 0.30% of cases versus 0.09% of controls (P=0.007) and deletions in 0.12 % of cases and 0.04% of controls (P>0.05). The region can be divided into three intervals defined by flanking low copy repeats. Duplications spanning intervals I and II showed the most significant (P = 0.00010) association with schizophrenia. The age of onset in duplication and deletion carriers among cases ranged from 12 to 35 years, and the majority were males with a family history of psychiatric disorders. In a single Icelandic family, a duplication spanning intervals I and II was present in two cases of schizophrenia, and individual cases of alcoholism, attention deficit hyperactivity disorder and dyslexia. Candidate genes in the region include NTAN1 and NDE1. We conclude that duplications and perhaps also deletions of chromosome 16p13.1, previously reported to be associated with autism and MR, also confer risk of schizophrenia.

A verbal planning impairment in adult ADHD indexed by script generation tasks

OBJECTIVE

Though juvenile and adult ADHD cases are well known to have a nonverbal planning impairment, a verbal-planning impairment has been demonstrated only in juvenile ADHD. The purpose of this investigation is to determine whether a verbal planning impairment also characterizes adult ADHD.

METHODS

A cohort of 30 adult ADHD clients of a university psychological clinic are compared to 30 age-, education-, gender-, and IQ-matched persons recruited from the general population who did not have ADHD. The dependent measure is a set of 6 paper/pencil 10-item script generation tasks.

RESULTS

The findings reveal that the ADHD cohort was significantly impaired on the script task and the script task correlated significantly with severity of ADHD (CAARS index + WURS), whereas several neuropsychological measures of executive function (Stroop, COWA, Rey's Complex Figure, D2, CVLT, CPT-II) did not. Findings further showed that the script measure was weakly correlated with the other established neuropsychological measures of executive function (r < .46, shared variance of less than 21%).

CONCLUSIONS

On the basis of the study findings, it is concluded that verbal planning measured with script generation tasks is distinctly impaired in clinically referred adult ADHD.