Kate Arron

The prevalence and phenomenology of self-injurious and aggressive behaviour in genetic syndromes.

BACKGROUND Self-injurious and aggressive behaviours are reported as components of some behavioural phenotypes but there are few studies comparing across syndrome groups. In this study we examined the prevalence of these behaviours and the associated person characteristics in seven genetic syndromes. METHODS Questionnaire data on self-injury and aggression, mood, hyperactivity, autism spectrum disorder and repetitive behaviour were collected on Angelman (AS, n=104), Cornelia de Lange (CdLS, 101), Cri du Chat (CdCS, 58), Fragile X (FXS, 191), Lowe (LS, 56), Prader-Willi (PWS, 189) and Smith-Magenis (SMS, 42) syndromes. RESULTS A significantly higher prevalence of self-injury was evident in CdCS, CdLS, FXS, PWS, LS and SMS. The prevalence of aggression was significantly heightened in AS and SMS. Self-injury was associated with repetitive and impulsive behaviour in CdLS, FXS, PWS and LS. Impulsivity and overactivity were significantly higher in those showing aggression across all syndrome groups. CONCLUSIONS These data quantify the risk for self-injury and aggression in the syndromes studied with implications for early intervention. The associations between these behaviours and person characteristics both within and between syndromes warrant further research.

Behavioural phenotype of Cornelia de Lange syndrome: case–control study

BACKGROUND Cornelia de Lange syndrome is associated with abnormalities on chromosomes 5, 10 and X. AIMS To delineate the behavioural phenotype of Cornelia de Lange syndrome with specific reference to autistic-spectrum disorder. METHOD A total of 54 individuals with Cornelia de Lange syndrome (mean age 13.88 years; s.d.=8.58) and 46 comparable individuals with intellectual disability (mean age 13.74 years; s.d.=7.99) were assessed on measures of autistic-spectrum disorder, and adaptive, compulsive and disordered behaviour. RESULTS There was no difference between the groups in global behaviour disorder. Severe autism was significantly more prevalent in the syndrome group (32.1%) than the comparison group (7.1%). In addition, the syndrome group also evidenced significantly higher levels of compulsive behaviour. CONCLUSIONS These data suggest that autistic-spectrum disorder is part of the behavioural phenotype of Cornelia de Lange syndrome and that compulsive behaviours are evident. Future research should investigate this behavioural phenotype using contemporary diagnostic algorithms for autism with detailed examination of the phenomenology of compulsive behaviours.

The association between repetitive behaviours, impulsivity and hyperactivity in people with intellectual disability.

BACKGROUND There is a need for assessments of psychological difference and disorder in people who have more severe intellectual disability (ID). Hyperactivity and impulsivity are two behavioural domains of importance as they are correlated with self-injury and aggression and this alludes to a shared cognitive correlate of compromised behavioural inhibition. Additionally, compromised behavioural inhibition is demonstrably related to repetitive behaviour and the latter might be expected to be associated with impulsivity and hyperactivity. METHODS The Activity Questionnaire (TAQ) was developed for this study. Three sub-scales with high levels of face validity were supported by factor analysis of the scoring of 755 intellectually disabled participants on the TAQ items. These sub-scales mapped onto the constructs of Overactivity, Impulsivity and Impulsive Speech. Test-retest, inter-rater reliability and internal consistency were robust. TAQ scores and scores on the Repetitive Behaviour Questionnaire (RBQ) were collected for a sample of 136 participants with varying degrees of ID. RESULTS Scores on the TAQ at sub-scale and full-scale level were not related to level of adaptive functioning. There were significant positive associations between overactivity (TAQ) and stereotyped behaviour (RBQ), impulsivity (TAQ) and restricted preferences (RBQ), and impulsive speech (TAQ) and repetitive speech (RBQ). CONCLUSIONS The TAQ is a reliable assessment of hyperactivity and impulsivity for people with ID with robust factor structure. Validity requires evaluation. The relationship between impulsivity and restricted preferences may result from a common cognitive impairment in inhibition, which may underpin these two classes of behaviour.

Health and Sleep Problems in Cornelia de Lange Syndrome: A Case Control Study.

BACKGROUND Self-injury, sleep problems and health problems are commonly reported in Cornelia de Lange Syndrome (CdLS) but there are no comparisons with appropriately matched participants. The relationship between these areas and comparison to a control group is warranted. METHOD 54 individuals with CdLS were compared with 46 participants with intellectual disability (ID) of mixed aetiology who were similar in terms of degree of ID, mobility, age and gender using informant-based measures of health problems, sleep and self-injury. RESULTS Participants with CdLS experienced significantly more current and lifetime health problems with eye problems and gastrointestinal disorders prominent. Although 55% of those with CdLS experienced sleep problems this prevalence was not different from the comparison group. Sleep disorder was not associated with self-injury in the CdLS group, skin problems were associated with severity of self-injury but not presence. DISCUSSION People with CdLS experience a range of significant health problems and have more health concerns than others with the same degree of ID. Although this has been well documented in the past, the current high prevalence of health concerns indicates the need for regular health assessment and appropriate intervention.

Self-injurious behaviour in Cornelia de Lange syndrome: 1. Prevalence and phenomenology

BACKGROUND Self-injurious behaviour is frequently identified as part of the behavioural phenotype of Cornelia de Lange syndrome (CdLS). We conducted a case-control study of the prevalence and phenomenology of self-injurious behaviour (SIB) in CdLS. METHODS A total of 54 participants with CdLS were compared with 46 individuals who were comparable on key variables including age, degree of intellectual disability and wheelchair use, using questionnaire and observational measures. RESULTS Clinically significant self-injury was not more prevalent in the CdLS group (55.6%), nor was it different in presentation from that seen in the comparison group. Hyperactivity, stereotyped and compulsive behaviours predicted clinically significant self-injury in all participants. Hand directed, mild self-injury was more prevalent in CdLS. CONCLUSIONS The results show that clinically significant self-injury may not be part of the behavioural phenotype of CdLS but a specific body target for proto-SIB is more common.

Effects of Social Context on Social Interaction and Self-Injurious Behavior in Cornelia de Lange Syndrome

Cornelia de Lange syndrome is reported to be associated with self-injurious behavior (SIB) and social avoidance. We used analog methodology to examine the effect of manipulating adult social contact on social communicative behaviors and SIB in 16 children with this syndrome. For 9 participants engagement behavior was related to levels of adult attention, and SIB showed significant variability across conditions for 3 participants. These findings indicate that SIB can be affected by environmental factors, even though it is thought to be part of the behavioral phenotype of Cornelia de Lange syndrome and suggest that individuals with this syndrome show socially motivated attention-soliciting behaviors. The implications for gene-environment interactions are discussed.

Phenomenology of Self-Restraint

Self-restraint is often reported in individuals with mental retardation who show self-injurious behavior (SIB). In this study, the phenomenology and prevalence of self-restraint in individuals showing self-injury and wearing protective devices and those showing self-injury but not wearing protective devices were compared. A high prevalence of self-restraint in the whole sample of individuals showing self-injury was identified (67/88, 76.1%), and self-restraint was more prevalent in a group showing self-injury but not wearing protective devices (43/47, 91.5%) than in a group showing self-injury and wearing protective devices (24/41, 58.5%). Individuals not wearing protective devices showed a greater number of topographies of self-restraint than those who did wear them. Results are discussed with reference to the purely topographical definition of self-restraint employed and the potential equivalence of protective devices and self-restraint.