The purported association between depression, aggression, and self-injury in people with intellectual disability: a critical review of the literature

Measurement tools for behaviours that challenge and behavioural function in people with intellectual disability: A systematic review and meta-analysis of internal consistency, inter-rater reliability, and test-retest reliability

Behaviours that challenge (BtC) are common in people with intellectual disability (ID) and associated with negative long-term outcomes. Reliable characterisation of BtC and behavioural function is integral to person-centred interventions. This systematic review and meta-analytic study quantitatively synthesised the evidence-base for the internal consistency, inter-rater reliability, and test-retest reliability of measures of BtC and behavioural function in people with ID (PROSPERO: CRD42021239042). Web of Science, Embase, PsycINFO and MEDLINE were searched from inception to March 2024. Retrieved records (n = 3691) were screened independently to identify studies assessing eligible measurement properties in people with ID. Data extracted from 83 studies, across 29 measures, were synthesised in a series of random-effects meta-analyses. Subgroup analyses assessed the influence of methodological quality and study-level characteristics on pooled estimates. COSMIN criteria were used to evaluate the measurement properties of each measure. Pooled estimates ranged across measures: internal consistency (0.41-0.97), inter-rater reliability (0.29-0.93) and test-retest reliability (0.52-0.98). The quantity and quality of evidence varied substantially across measures; evidence was frequently unavailable or limited to a single study. Based on current evidence, candidate measures with the most evidence for internal consistency and reliability are discussed; however, continued assessment of measurement properties in ID populations is a key priority.

Characteristics of children with autism and unspecified intellectual developmental disorder (intellectual disability) presenting with severe self-injurious behaviours

Objective: This study aims to delineate the characteristics of severe self-injurious behaviors (SIB) in a cohort of children with autism and unspecified intellectual developmental disorder (UIDD) (intellectual disability) and examine potential risk factors for developing SIB. Methods: A retrospective chart review studied characteristics of severe SIB in 30 children with autism spectrum disorder (ASD) and UIDD referred to a tertiary care center. Characteristics examined include genetic syndromes, brain MRI abnormalities, verbal ability, adaptive functioning, SIB frequency and severity, age of onset, number of psychopharmacological agents, irritability, hyperactivity, stereotypy, psychiatric and physical comorbidities, among others. Descriptive and bivariate analysis were applied to explore potential relationships between factors. Results: Children with severe SIB exhibit this behaviour with high frequency, inflicting moderate to severe injury. Most children in the study sample are non-verbal and have ASD (93.3%; n = 28) with psychiatric (96.7%; n = 29) and physical (90%; n = 27) comorbidities. Overall SIB improvement using the Clinical Global Impression, Improvement Score (CGI-I) was 3.0 (minimally improved). A minority were much or very much improved following appropriate intervention. Conclusions: The severity of SIB is much higher in this sample than previously noted in the literature. Severe SIB is associated with ADHD, early onset mood disorders, tics, avoidant restrictive food intake disorder and Obsessive-Compulsive Disorder.

The Impact of COVID-19 Restrictions on Psychological Distress in Family Caregivers of Children with Neurodevelopmental Disability in the UK

Caregivers of a child with a neurodevelopmental disability are more vulnerable to mental health difficulties. These difficulties are influenced by the child’s challenging behaviours, and the caregiver’s coping strategies; factors impacted by the COVID-19 pandemic. An online mixed methods survey was conducted on caregivers of children with neurodevelopmental disabilities (n = 43) and children who are typically developing (n = 67). The results showed that presence of challenging behaviours related to neurodevelopmental disability, and caregiver coping strategies predicted caregiver psychological distress during lockdown. Themes that emerged included ‘confusing messages and guidance’, ‘loss of freedom’ and ‘unsupported and forgotten’. The results demonstrate the pressing need for the implementation of appropriate support to protect the mental health of caregivers across the UK.

Development and Validation of a Multi-informant Measure of Social Behaviors for Youth with Intellectual Disabilities

Youth with intellectual disability (ID) are at an increased risk of displaying fewer prosocial behaviors and more numerous aggressive behaviors in various environments. This study proposes a new multi-informant (youth, teachers, and parents) measure of social behaviors for youth with ID. The sample includes 348 youth with mild (51.41%) and moderate (48.59%) levels of ID, aged 11-22 years old (M = 15.73, SD = 2.14; including 138 females), enrolled in secondary schools in Canada (French-speaking; N = 116; 33.33%) and Australia (English-speaking; N = 232; 66.67%). Measures were completed by the participants, their teachers, and their parents. Results support the reliability, factor validity, discriminant validity (in relation to sex, ID level, and country), concurrent validity (with measures of victimization, depression, hyperactivity-inattention), and one-year test-retest stability of the measure. Youth, teachers, and parents all provided a complementary perspective on youth social behaviors, consistent with youth adjusting their behaviors to the various environments in which they share social interactions.

Testing a Wellness Indicators Measure for People with Intellectual and Developmental Disabilitiesa

BACKGROUND AND PURPOSE

People with intellectual and developmental disabilities (IDD) often have health and wellness issues that are not as good as people without disabilities. States are required to monitor health and wellness for people with IDD who use many disability services. However, there are few ways to monitor wellness between states or at different points in time. In this study, we share a new model that states may use to monitor wellness of people with IDD.

METHODS

We used data from a survey called the National Core Indicators (NCI) to develop this model. First, we developed the model using our state's data. Then, after we found a model that worked well, we tested that model using the National Core Indicators from the entire U.S.

RESULTS

Our final model worked well in both our state NCI data and the national NCI data. This is important because policies at both levels can affect the services that people with disabilities can use. Our model had three parts: heart health, mental health, and behavioral wellness. These are described more in the paper. We also used statistics to test some factors that might predict outcomes related to heart health, mental health, and behavioral wellness. Age, sex, where someone lives, and level of intellectual disability were all good predictors of all three categories of wellness that we studied.

IMPLICATIONS

The model of wellness that we developed worked well but should be tested using data from other individual states. It is very important to know about health and wellness right now since the services people with disabilities can use are changing in many states. We think our model can help planners and advocates understand how services affect wellness in a way that is easy to compare from state to state and at different points in time.

The evolution of self-injurious behaviors in people with intellectual disability and epilepsy: A follow-up study

PURPOSE

Longitudinal studies of the evolution of Self-Injurious Behaviors (SIBs) in people with Intellectual Disability (ID) and epilepsy are not common. This study aimed to analyze the evolution (in terms of remission and persistence) and changes in the type, localization, frequency, and intensity of SIBs.

METHODS

SIBs were assessed in a sample of 52 people with ID and epilepsy, and re-evaluated after a seven-year interval, using the "Scale for the Assessment of Self-Injurious Behaviors". The scale was administered to caregivers (parents or health professionals) through a semi-structured interview conducted by a specifically trained psychologist.

RESULTS

The most frequent types of SIBs identified were: self-biting, self-hitting with objects, self-hitting with hand, object-finger in cavities. The main localizations of SIBs were: hands, mouth, head and cheeks. SIBs were found to be maintained after seven years, for type, localization, frequency, and intensity, in 90.4% of the sample. SIB types were stable over time, as were the affected areas. Global SIB frequency and intensity scores were found to be unchanged. Finally, a positive correlation was found between the frequency of SIBs and levels of intellectual disability. SIBs (frequency and intensity) and seizure frequency showed no correlation.

CONCLUSION

Given the negative impact of SIBs on the adaptation and quality of life of people with ID and epilepsy, we believe that further studies on biological, psychological and environmental aspects are needed in order to identify any potential factors that might explain the persistence of SIBs and to find effective interventions to reduce them.

Factors affecting the relationship between adaptive behavior and challenging behaviors in individuals with intellectual disability and co-occurring disorders

Previous studies have reported an inverse relationship between adaptive behavior and challenging behaviors in individuals with ID. However, it is unclear which characteristics might influence this relationship in individuals with ID and co-occurring conditions. We found a positive correlation between adaptive behavior (Vineland-II) and challenging behaviors (Nisonger Child Behavior Rating Form) in a study of 105 individuals who presented with mostly severe to profound ID and comorbid physical and mental health conditions. These results might be the consequence of the individual participant characteristics. Therefore, participants were separated out into two groups representing the top (n = 24) and bottom quartiles (n = 28) for presence of challenging behaviors. The participants with the highest levels of challenging behaviors had higher levels of adaptive behavior, higher frequency of intermittent explosive/conduct disorder, but lower frequency of epilepsy and cerebral palsy. All participants with the highest levels of challenging behaviors lived in an institutional setting; whereas, those with the lowest level of challenging behaviors lived in either an institutional setting or with their family. In participants with severe/profound ID and multiple co-occurring disorders, a minimum level of adaptive behavior seems to be necessary for the expression of challenging behaviors.

Persistence and predictors of self-injurious behaviour in autism: a ten-year prospective cohort study

Background

Self-injurious behaviours, such as head banging, hair pulling, skin picking and scratching, are common in individuals with autism. Despite high prevalence rates, there is a paucity of longitudinal research to refine models of risk and mechanism and inform service planning. In this longitudinal study, we investigated self-injury in a cohort of individuals with autism over 10 years to identify behavioural and demographic characteristics associated with persistent self-injury.

Methods

Carers of 67 individuals with autism completed questionnaires relating to the presence of self-injury and relevant risk markers at T1 (mean [SD] age in years 13.4 [7.7]) and T3 (mean [SD] age in years 23.9 [7.7]) 10 years later. Forty-six of these also took part at T2 (3 years after initial participation). Analysis assessed demographic and behavioural risk markers for self-injury, as well as the predictive value of items assessed at T1and T2.

Results

Self-injury was persistent in 44% of individuals over the 10-year period, with behavioural characteristics of impulsivity (p < .001) and overactivity (p = .002), identified as risk markers for persistence. A predictive model of self-injury was derived from LASSO analysis, with baseline impulsivity, interest and pleasure, stereotyped behaviour, social communication and adaptive functioning predicting self-injury over 10 years.

Conclusions

In this unique longitudinal investigation into the persistence of self-injury in a non-clinical sample of individuals with autism over a 10 year period, we have identified a novel, robust and stable profile of behavioural characteristics associated with persistent self-injury. Findings support an early intervention strategy targeted towards individuals identified to be at a higher risk of developing self-injurious behaviour.

The role of anxiety in vulnerability for self-injurious behaviour: studies in a rodent model

Self-injurious behaviour (SIB) is a debilitating characteristic that is highly prevalent in autism and other neurodevelopmental disorders. Pathological anxiety is also common, and there are reports of comorbid anxiety and self-injury in some children. We have investigated potential interactions between anxiety and self-injury, using a rat model of pemoline-induced self-biting. In one experiment, rats were pre-screened for trait anxiety by measuring expression of anxiety-related behaviour on the elevated plus maze and open field emergence test. The rats were then treated with pemoline once daily for ten days, and vulnerability for pemoline-induced self-injury was evaluated. This revealed modest correlations between innate levels of anxiety-related behaviour in the open field test (time in the start box, and latency to enter the open field), and vulnerability for pemoline-induced self-biting (total duration of self-injurious oral contact, and total size of tissue injury). Measures in the elevated plus maze were not significantly correlated with vulnerability for pemoline-induced self-injury. In a second experiment, rats were treated with the beta-carboline FG 7142 twice daily, during 5days of treatment with pemoline. The rats that were treated with this anxiogenic drug exhibited greater duration of self-injurious oral contact, and larger injuries than vehicle-treated controls did. Overall, these results suggest that anxiety may contribute to the etiology and/or expression of self-injurious behaviour, and indicate that further research is warranted.

Brief Symptom Inventory symptom profiles of outpatients with borderline intellectual functioning and major depressive disorder or posttraumatic stress disorder: Comparison with patients from regular mental health care and patients with Mild Intellectual Disabilities

INTRODUCTION

In most countries, people with borderline intellectual functioning (BIF) are not considered a separate group in mental health care. There is little to no research on the impact of BIF on the presentation, nature and severity of mental health problems. The aim of the present exploratory study was to compare, in a naturalistic setting of patients referred to secondary care, symptom profiles of patients with BIF diagnosed with either major depressive disorder (MDD) or posttraumatic stress disorder (PTSD) to patients from regular mental health care (RMHC) and patients with Mild ID diagnosed with the same disorders.

METHODS

We used a cohort of adolescent and adult outpatients (aged 16-88) with or without BIF diagnosed with a primary diagnosis MDD or PTSD. Primary outcome was the nature and severity of psychopathological symptoms assessed at baseline using the Brief Symptom Inventory. All outcomes were adjusted for gender and age.

RESULTS

Results showed that BIF patients with a primary diagnosis MDD reported less severe symptoms on BSI Total and the subscales Depression, Obsession-Compulsion and Psychoticism than patients from regular mental health care (RMHC). There were no statistically significant differences in reported symptom severity on BSI Total and the different BSI subscales between BIF patients with PTSD and either patients from RMHC or patients with Mild ID. Patients Mild ID, did report significantly less severe symptoms on the subscale Depression and on the subscale Psychoticism than patients from RMHC.

DISCUSSION

Since there were no other published studies into symptom profiles in patients with BIF compared to either patients with higher or lower levels of cognitive functioning, the study was mainly exploratory in nature, providing direction for future research. Results indicate that symptom profiles did not widely differ, but that there might be some characteristics unique to patients BIF separating them as a group from both patients from RMHC and patients with Mild ID.

Practitioner Review: Self-injurious behaviour in children with developmental delay

BACKGROUND

Self-injurious behaviour is shown by a significant minority of children with developmental delay and has a substantial impact on child and carer wellbeing. Characteristics such as a greater degree of intellectual disability, autism spectrum disorder, some genetic syndromes and repetitive and impulsive behaviours are positively associated with self-injury. Prevalence generally increases with age into midadulthood and the behaviour is notably persistent.

SCOPE

In this review, we discuss the dominant causal theory of self-injury which draws on the principles of operant learning. We evaluate the utility of this theory to account for all empirical observations of self-injury.

FINDINGS

A model of self-injury is presented that extends a previous model described by Guess and Carr. The new model integrates child characteristics and operant learning principles in a phenotype × environment paradigm to explain the variance in developmental trajectory of the severity of self-injury.

CONCLUSIONS

Behaviour dysregulation, as evidenced by the associations between self-injury, self-restraint, repetitive and impulsive behaviours, is identified as potentially influencing the severity and persistence of self-injury. Risk markers for self-injury are identified and the extended model indicates points of intervention and highlights the possibility of risk-related, targeted early intervention. The need for increased training of practitioners in the delivery of demonstrably effective interventions for self-injury is identified.

Comparative analysis of self-injury in people with psychopathology or neurodevelopmental disorders

Self-injury is a complex and poorly understood behavior observed in people with psychopathology or neurodevelopmental disorders (NDD). Despite the differences in etiology and progression of these distinct disease domains, it is possible that overlapping molecular pathways underlie the expression of self-injurious behaviors (SIBs). This review outlines the similarities and differences at the behavioural and molecular level, where SIBs in both conditions may involve opioid, nucleoside, and dopamine signalling. These points of convergence have important implications for treatment and research of SIB in both populations.