L. de Sonneville

Interventions to improve adherence to antipsychotic medication in patients with schizophrenia–A review of the past decade

OBJECTIVE Nonadherence to antipsychotic medication is highly prevalent in patients with schizophrenia and has a deleterious impact on the course of the illness. This review seeks to determine the interventions that were examined in the past decade to improve adherence rates. METHOD The literature between 2000 and 2009 was searched for randomized controlled trials which compared a psychosocial intervention with another intervention or with treatment as usual in patients with schizophrenia. RESULTS Fifteen studies were identified, with a large heterogeneity in design, adherence measures and outcome variables. Interventions that offered more sessions during a longer period of time, and especially those with a continuous focus on adherence, seem most likely to be successful, as well as pragmatic interventions that focus on attention and memory problems. The positive effects of adapted forms of Motivational Interviewing found in earlier studies, such as compliance therapy, have not been confirmed. CONCLUSION Nonadherence remains a challenging problem in schizophrenia. The heterogeneity of factors related to nonadherence calls for individually tailored approaches to promote adherence. More evidence is required to determine the effects of specific interventions.

Inhibition of prepotent responding and attentional flexibility in treated phenylketonuria

Inhibition of prepotent responding and attentional flexibility were assessed in 58 early and continuously treated phenylketonuria (PKU) patients and 69 controls, age 7 to 14 years. A computerized task was used requiring participants to process consecutive stimuli according to various attentional sets. Analysis of error rate suggested poorer inhibition of prepotent responding in PKU patients compared with controls. No influence of concurrent plasma phenylalanine (phe) was shown, neither in the younger (age < 11 years) nor in the older participants (age sup3; 11 years). Analysis of error rate provided strong evidence for poorer attentional flexibility in PKU patients compared with controls. The difference between attentional flexibility in controls and PKU patients could mainly be attributed to younger PKU patients, with concurrent phe levels higher than 360μmol/L.Younger PKU patients with phe levels below 360 μmol/L performed at the same level as age-matched controls. Performance of PKU patients was strongly associated with phe levels in age periods during the first 10 years of life, which are characterized by a strong development of executive functioning (ages 2-7 and age 9). High phe levels during these age periods could delay development of inhibitory control and attentional flexibility. With regard to treatment, analyses with lifetime and concurrent phe levels support strict dietary control throughout the first decade of life, after which the phe-restricted diet can be relaxed. However, based on the evidence that development of specific executive functions continues until approximately age 12, it is recommended to maintain phe levels below 360 μmol/L throughout early adolescence.

Misattribution of facial expressions of emotion in adolescents at increased risk of psychosis: the role of inhibitory control.

BACKGROUND By studying behavior, cognitive abilities and brain functioning in adolescents at high risk for psychosis, we can gain an insight into the vulnerability markers or protective factors in the development of psychotic symptoms. Although many high-risk studies have focused on impairments in neurocognitive functions, such as memory and attention, very few studies have investigated problems in processing social cues such as facial expressions as a possible vulnerability marker for psychosis. METHOD Thirty-six adolescents at ultra-high risk (UHR) for psychosis and 21 non-clinical controls completed a face recognition test, a facial affect labeling test and an inhibitory control test. Schizotypal traits and schizophrenia symptoms were assessed using a schizotypy questionnaire and the Positive and Negative Syndrome Scale (PANSS). RESULTS The UHR group showed impairments in labeling facial expressions of others, in addition to a spared ability to recognize facial identity. More specifically, the UHR group made more errors in labeling neutral expressions compared to the controls, and an analysis of error types indicated that neutral faces were misattributed as being angry. The degree of misattribution of neutral-as-angry faces correlated significantly with reduced inhibitory control. CONCLUSIONS Our findings suggest that misattributing social cues might contribute to vulnerability for psychosis. This social cognitive deficit may be related to problems in inhibitory control, which potentially plays an important role in the selection of appropriate social meaning. These findings may have relevance for understanding the mechanisms underlying prodromal social dysfunction, which should be targeted in future remediation interventions.

Specific Memory Impairment Following Neonatal Encephalopathy in Term-Born Children

This study examines short-term memory, verbal working memory, episodic long-term memory, and intelligence in 32 children with mild neonatal encephalopathy (NE), 39 children with moderate NE, 10 children with NE who developed cerebral palsy (CP), and 53 comparison children, at the age of 9 to 10 years. Results: in addition to a global effect on intelligence, NE had a specific effect on verbal working memory, verbal and visuo-spatial long-term memory, and learning, which was associated with degree of NE. Although these memory problems occurred in children without CP, they were more pronounced when children had also developed CP.

In search for significant cognitive features in Klinefelter syndrome through cross-species comparison of a supernumerary X chromosome.

The behavioral characterization of animals that carry genetic disorder abnormalities in a controlled genetic and environmental background may be used to identify human deficits that are significant to understand underlying neurobiological mechanisms. Here, we studied whether previously reported object recognition impairments in mice with a supernumerary X chromosome relate to specific cognitive deficits in Klinefelter syndrome (47,XXY). We aimed to optimize face validity by studying temporal object recognition in human cognitive assays. Thirty‐four boys with Klinefelter syndrome (mean age 12.01) were compared with 90 age‐matched normal controls, on a broad range of visual object memory tasks, including tests for pattern and temporal order discrimination. The results indicate that subjects with Klinefelter syndrome have difficulty in the processing of visual object and pattern information. Visual object patterns seem difficult to discriminate especially when temporal information needs to be processed and reproduced. On the basis of cross‐species comparison, we propose that impaired temporal processing of object pattern information is an important deficit in Klinefelter syndrome. The current study shows how cross‐species behavioral characterization may be used as a starting point to understand the neurobiology of syndromal phenotypic expression. The features of this study may serve as markers for interventions in Klinefelter syndrome. Similar cross‐species evaluations of standard mouse behavioral paradigms in different genetic contexts may be powerful tools to optimize genotype–phenotype relationships.

Intellectual functioning in relation to autism and ADHD symptomatology in children and adolescents with 22q11.2 deletion syndrome

BACKGROUND The 22q11.2 deletion syndrome (22q11DS; velo-cardio-facial syndrome) is associated with an increased risk of various disorders, including autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD). With this study, we aimed to investigate the relation between intellectual functioning and severity of ASD and ADHD symptomatology in 22q11DS. METHOD A sample of 102 individuals (62 females) with 22q11DS aged 9 to 18.5 years were assessed using age appropriate Wechsler scales of intelligence as well as psychological and psychiatric assessment to evaluate the presence of ASD and ADHD symptomatology. RESULTS Intelligence profiles were characterised by lower scores on the factor perceptual organisation and higher scores on the factor processing speed, with on subtest level higher scores on digit span and lower scores on arithmetic and vocabulary as compared with the mean factor or subtest score respectively. No differences in intelligence profiles were found between subgroups with and without ASD and/or ADHD. Low scores on coding were associated with higher severity of ASD symptomatology, while lower scores on block design were associated with more severe ADHD symptomatology. CONCLUSIONS On several sub-domains of intelligence, poorer performance was associated with higher severity of ASD and ADHD symptomatology. The impact of developmental disorders in 22q11DS can be traced in specific domains of intellectual functioning as well as in severity of symptomatology.

The role of COMT and plasma proline in the variable penetrance of autistic spectrum symptoms in 22q11.2 deletion syndrome

This paper examines how COMT158 genotypes and plasma proline levels are associated with variable penetrance of social behavioural and social cognitive problems in 22q11.2 deletion syndrome (22q11DS). Severity of autistic spectrum symptoms of 45 participants with 22q11DS was assessed using the Autism Diagnostic Interview Revised. Face and facial emotion recognition was evaluated using standardized computer‐based test‐paradigms. Associations with COMT158 genotypes and proline levels were examined. High proline levels and poor face recognition in individuals with the COMTMET allele, and poor facial emotion recognition, explained almost 50% of the variance in severity of autism symptomatology in individuals with 22q11DS. High proline levels and a decreased capacity to break down dopamine as a result of the COMTMET variant are both relevant in the expression of the social phenotype in patients. This epistatic interaction effect between the COMT158 genotype and proline on the expression of social deficits in 22q11DS shows how factors other than the direct effects of the deletion itself can modulate the penetrance of associated cognitive and behavioural outcomes. These findings are not only relevant to our insight into 22q11DS, but also provide a model to better understand the phenomenon of variable penetrance in other pathogenic genetic variants.

The nature of social cognitive deficits in children and adults with Klinefelter syndrome (47,XXY)

About 1 in 650 boys are born with an extra X chromosome (47,XXY or Klinefelter syndrome). 47,XXY is associated with vulnerabilities in socio‐emotional development. This study was designed to assess types of cognitive deficits in individuals with 47,XXY that may contribute to social‐emotional dysfunction, and to evaluate the nature of such deficits at various levels: ranging from basic visuospatial processing deficits, impairments in face recognition (FR), to emotion expression impairments. A total of 70 boys and men with 47,XXY, aged 8 to 60 years old, participated in the study. The subtests feature identification, FR and identification of facial emotions of the Amsterdam Neuropsychological Tasks were used. Level of intellectual functioning was assessed with the child and adult versions of the Wechsler Intelligence Scales. Reaction time data showed that in the 47,XXY group, 17% had difficulties in visuospatial processing (no social load), 26% had difficulties with FR (medium social load) and an even higher number of 33% had difficulties with facial expressions of emotions (high‐social load). Information processing impairments increased as a function of “social load” of the stimuli, independent of intellectual functioning. Taken together, our data suggest that on average individuals with XXY may have more difficulties in information processing when “social load” increases, suggesting a specific difficulty in the higher‐order labeling and interpretation of social cues, which cannot be explained by more basic visuospatial perceptual skills. Considering the increased risk for social cognitive impairments, routine assessment of social cognitive functioning as part of neuropsychological screening is warranted.