Caregiver Perspectives on Pain Sensitivity and Pain Experience in Rett Syndrome.

Background: Although delayed or decreased responses to pain are commonly reported among caregivers of individuals with Rett syndrome (RTT), previous studies in relatively small samples have documented that caregivers are concerned about pain, particularly due to gastrointestinal and musculoskeletal conditions. Aims: The purpose of the current study was to investigate in detail caregivers' perceptions of pain sensitivity, as well as the types, severity, and effect of pain experienced by individuals with RTT in a larger sample than previous studies. Methods: A total of 51 caregivers (mostly mothers) participated in the study, which involved standardized questionnaires and interviews. The individuals with RTT ranged in age from 2 to 52 years of age, and most (n = 46; 90%) met criteria for classic RTT. Results: Across the sample, 84% of caregivers reported that they believed that their child was less sensitive to pain compared to her typically developing peers. Despite this perception, 63% of caregivers reported that their child had experienced at least one form of pain in the previous 7 days, and 57% reported their child experienced at least one form of chronic pain. On average, caregivers reported that their child's pain was of moderate severity and interfered with at least one activity of daily living. Conclusions: The results suggest that pain is a substantial concern among caregivers of individuals with RTT and indicate that additional research is needed to understand the apparent paradox of frequently reported pain experiences despite widespread perceptions of decreased pain sensitivity.

Contexte: Bien que des réponses tardives ou diminuées à la douleur soient fréquemment signalées par les soignants de personnes atteintes du syndrome de Rett (RTT), des études antérieures dans des échantillons relativement petits ont documenté que les soignants étaient préoccupés par la douleur, en particulier en raison de troubles gastro-intestinaux et d'affections musculosquelettiques.Objectifs: Le but de la présente étude était d'étudier en détail les perceptions de la sensibilité à la douleur par les soignants ainsi que les types, la gravité et l'effet de la douleur ressentie par les personnes atteintes de RTT dans un échantillon plus important que les études précédentes.Méthodes: Au total, 51 soignants (principalement des mères) ont participé à l'étude, qui a eu recours à des questionnaires et à des entretiens standardisés. Les personnes atteintes de RTT étaient âgées de 2 à 52 ans, et la plupart (n = 46 ; 90 %) répondaient aux critères de la RTT classique.Résultats: Dans l'échantillon, 84 % des soignants ont déclaré qu'ils croyaient que leur enfant était moins sensible à la douleur par rapport à ses pairs qui se développent normalement. Malgré cette perception, 63 % des soignants ont signalé que leur enfant avait ressenti au moins une forme de douleur au cours des sept jours précédents, et 57 % ont déclaré que leur enfant avait souffert d'au moins une forme de douleur chronique. En moyenne, les soignants ont signalé que la douleur de leur enfant était d'intensité modérée et interférait avec au moins une activité de la vie quotidienne.Conclusions: Les résultats indiquent que la douleur est une préoccupation importante chez les soignants des personnes atteintes de RTT et que des études supplémentaires sont nécessaires pour comprendre le paradoxe apparent voulant que des expériences douloureuses soient fréquemment rapportées bien que la perception d'une diminution de la sensibilité à la douleur soit largement répandue.

Preliminary assessment of the reliability and validity of infrared skin temperature measurements in Rett syndrome.

BACKGROUND: As clinical trials for Rett syndrome are underway, there is a need to validate potential supplemental outcome measures that reflect important signs and symptoms. Autonomic dysfunction, particularly vasomotor dysfunction, is one potential area for which biomarkers could be developed. METHODS: In the current study, infrared thermal images of hands and feet from 26 females with Rett syndrome (aged 62 months to 39 years), and 17 females without known intellectual, genetic or neurological disorders (aged 55 months to 39 years) were collected. Between-group differences in skin temperature, and temporal stability of skin temperature measures in the Rett syndrome group, and relationships between skin temperature measures and parent-reported and researcher-evaluated indicators of autonomic dysfunction were evaluated. RESULTS: Between-group differences showed lower hand and foot temperatures in the Rett syndrome group. Hand temperature measurements were stable over time and were moderately correlated with parent-reported autonomic symptoms. Foot temperature measurements were more variable than hand temperatures but showed stronger correlations with parent-reported autonomic symptoms. CONCLUSIONS: The results provide preliminary support for the reliability and validity of hand and foot skin temperature measures in Rett syndrome. Additional research is needed to replicate these results and evaluate the temporal stability of these measures over shorter time scales.

Comparative analysis of self-injurious behaviour topographies in young children with and without developmental delay.

BACKGROUND: The present study presents post hoc analyses of specific topographies of self-injurious behaviour (SIB) exhibited by young children with developmental delay (DD) and children with typical development (TD). We conducted these analyses to better understand similarities and differences between the groups from a developmental perspective. No previous study has compared the prevalence, severity and co-occurrence of specific topographies of SIB in young children. METHOD: The participants were parents of two groups of children one with DD (n = 49, mean age = 37.5 months) and one with TD (n = 49, mean age = 36.6 months). Individual items of the SIB subscale from the Repetitive Behaviour Scale-Revised were used in the analyses. RESULTS: Seven of the eight Repetitive Behaviour Scale-Revised SIB categories were reported for both groups. Children in the DD group were significantly more likely to engage in Hits Self against Surface or Object, Hits Self with Body Part, Inserts Finger or Object, Skin Picking and Bites Self. Parental ratings of severity were also significantly greater for the DD group for these five topographies. The DD group engaged in a significantly greater number of SIB topographies than the children in the TD group. Children in the TD group were more likely to exhibit a single SIB topography while the DD group were more likely to engage in two or more topographies. Topographies involving self-hitting were not only more frequent among the children in the DD group but also more likely to be rated as moderate or severe in nature. CONCLUSIONS: Compared with the TD group, the topographies of SIB exhibited by the DD group were more prevalent, more severe and co-occurred with greater frequency. Inclusion of a group of children with TD provided an important comparative context for the occurrence of SIB in children with DD.

Coaching parents to assess and treat self-injurious behaviour via telehealth.

The application of telehealth technology to conduct functional analysis (FA) and functional communication training (FCT) is emerging for children with developmental disabilities and behaviour support needs. The current study was designed to extend FA + FCT for self-injurious behaviour by using telehealth in home with parents as interventionists receiving real-time remote coaching. Two families with school-aged boys with developmental disabilities associated with intellectual disability participated, one with cerebral palsy and the other with autism spectrum disorder. Results indicated that parent-implemented FA + FCT via telehealth was effective for reducing self-injurious behaviour and increasing mands (communication requests) for both children. Both families successfully implemented the FA + FCT protocol with 95% overall fidelity via telehealth-supported coaching. Results are discussed in terms of their relationship to previous research, limitations and future directions.

Perspectives on pain and intellectual disability.

Historically, individuals with intellectual disability (ID) have been excluded from pain research and assumed to be insensitive or indifferent to pain. The weight of the evidence suggests that individuals with ID have been subject to practices and procedures with little regard for their ability to experience or express pain. A number of issues central to improving understanding of pain in ID will be introduced and current research related to the definition of pain and its social context, underlying sensory and metabolic systems and factors influencing judgments about the ability to experience pain will be reviewed. Accumulating evidence from interdisciplinary research designed to improve assessment, understand individual differences, and evaluate bias and beliefs about pain suggests that new perspectives are emerging and beginning to shape an innovative frontier of research that will ultimately pay tremendous dividends for improving the quality of life of individuals with ID.

Blink rate in boys with fragile X syndrome: preliminary evidence for altered dopamine function.

BACKGROUND: Dopamine, a neurotransmitter involved in motor and cognitive functioning, can be non-invasively measured via observation of spontaneous blink rates. Blink rates have been studied in a number of clinical conditions including schizophrenia, autism, Parkinsons, and attention deficit/hyperactivity disorder with results implicating either hyper or hypo dopaminergic states. METHODS: This study examined spontaneous blink rate in boys with fragile X syndrome (FXS). Blink rates of boys (4-8 years old) with FXS (n = 6) were compared with those of age-matched typically developing boys (n = 6) during active and passive tasks. Blink rates (blinks per minute) for each task were compared between the two groups. Then, the relation between blink measures and core FXS-related features [problem behaviours, arousal, fmr 1 protein (FMRP)] were examined within the group of boys with FXS. RESULTS: Blink rate in boys with FXS was significantly higher than typically developing boys during passive tasks. Within the FXS group, there were significant correlations between blink rate and problem behaviours and physiological arousal (i.e. heart activity) but not with FMRP. CONCLUSIONS: Observed differences in spontaneous blink rate between boys with and without FXS and the relation between blink rate and physiological and behavioural measures in boys with FXS suggests that further work examining dopamine dysfunction as a factor in the pathophysiology of FXS may be warranted.

The early development of stereotypy and self-injury: a review of research methods.

BACKGROUND: The origin and developmental course of stereotypic and self-injurious behaviour among individuals with developmental disabilities such as intellectual disability (ID) or pervasive development disorders such as autism is not well understood. METHOD: Twelve studies designed to document the prevalence, nature, or development of stereotypic and/or self-injurious behaviour in children under 5 years of age and identified as at risk for developmental delay or disability were reviewed. Comparisons were made with similar studies with typically developing children. RESULTS: It appears that the onset of naturally occurring rhythmic motor stereotypies is delayed in young at-risk children, but that the sequencing may be similar. A very small database, differences in samples, measures, and designs limited the degree to which comparisons could be made across studies. CONCLUSION: Future work is needed based on appropriately designed prospective comparison studies and uniform quantitative measures to provide an empirical basis for new knowledge about the early development of one of the most serious behaviour disorders afflicting children with ID and related problems of development.

Sequential analysis of the effects of naltrexone on the environmental mediation of self-injurious behavior.

Accumulated evidence shows that biology and the environment can mediate self-injurious behavior (SIB) in persons with mental retardation. Whether pharmacological treatment alters the environmental mediation of self-injury is unclear. Opioid antagonist effects on sequential dependencies for self-injury were studied in the context of experimental single-subject double-blind placebo-controlled designs. Direct observational data were collected for 4 adult subjects in real time on daily rate of SIB and staff interactions. Clinically significant reductions (i.e., > or = 33%) in SIB rate were observed for 3 of the 4 subjects. For all subjects, the magnitude of the sequential dependency between staff behavior and self-injury was significantly greater during treatment with naltrexone than during treatment with a placebo. Results are discussed in relation to behavioral mechanisms of action regulating medication effects for self-injury.

Preliminary study of altered skin temperature at body sites associated with self-injurious behavior in adults who have developmental disabilities.

In this study, the sensory status of 4 nonverbal adults with mental retardation and severe self-injury was examined using skin temperature measures prior to opiate antagonist treatment. Double-blind, placebo-controlled, experimental ABAB designs were used to evaluate the effects of naltrexone hydrochloride (1.5 mg/kg/day). For each participant, the body site targeted most frequently for self-injury was associated with altered skin temperature and reduced by naltrexone. In all cases, neither infrequent self-injury body sites nor non-self-injury body sites were associated with altered skin temperature. Further controlled studies are warranted to examine the value of assessing pain status and skin temperature in nonverbal patients with mental retardation and related developmental disabilities who present with tissue-damaging SIB.

Varieties of repetitive behavior in autism: comparisons to mental retardation.

Systematic study of abnormal repetitive behaviors in autism has been lacking despite the diagnostic significance of such behavior. The occurrence of specific topographies of repetitive behaviors as well as their severity was assessed in individuals with mental retardation with and without autism. The occurrence of each behavior category, except dyskinesias, was higher in the autism group and autistic subjects exhibited a significantly greater number of topographies of stereotypy and compulsions. Both groups had significant patterns of repetitive behavior co-occurrence. Autistic subjects had significantly greater severity ratings for compulsions, stereotypy, and self-injury. Repetitive behavior severity also predicted severity of autism. Although abnormal repetition is not specific to autism, an elevated pattern of occurrence and severity appears to characterize the disorder.

Self-injurious behavior and sleep disturbance in adults with developmental disabilities.

Sleep patterns of 30 individuals with self-injurious behavior and mental retardation were compared with those of 30 matched controls residing in the same residential facility that did not self-injure. Individuals were recorded as asleep or awake during 30 min intervals for eight hours per night. The results of a Wilcoxon signed-ranks test (p < .05) indicated that individuals with self-injury slept significantly less than individuals without self-injury. chi2 analyses (p < .01) indicated significantly greater variability in the number of intervals recorded as asleep among individuals with self-injury than their matched controls. These results are congruent with previous findings of sleep disturbance among persons with mental retardation and behavior problems. The possibility of neurochemical dysregulation in sleep disturbance among individuals with daytime self-injury is discussed.

Treatment of self-injurious behavior and quality of life for persons with mental retardation.

Self-injurious behavior (SIB) is a highly problematic and damaging behavior with profound implications for a person's quality of life. Despite numerous reports documenting changes in self-injury, it is not well-known how these changes relate to systematic improvements in quality of life. We surveyed 41 journals from 1978 to 1996 to identify use of quality of life outcome measures following self-injury treatment. A sample of 138 research articles involving 436 subjects with self-injury was reviewed. Forty articles (29%) were found that contained some quality of life measure. Very little detailed information was available concerning the specific nature of change in life-style based on immediate changes in SIB. This lack of information and its possible implications are discussed.

Self-injurious behavior and Prader-Willi syndrome: behavioral forms and body locations.

With few exceptions (e.g., Lesch-Nyhan syndrome), the specific nature of self-injury in relation to identified genetic syndromes associated with mental retardation is poorly understood. In the present study we surveyed the families of 62 persons with Prader-Willi syndrome to determine the prevalence, topographies, and specific body locations of self-injurious behavior. Self-injury was reported for 81% of the participants. Skin-picking was the most prevalent form, with the front of the legs and head being disproportionately targeted as preferred self-injury body sites. Individuals with the 15q11-q13 deletion injured significantly more body sites than did individuals with maternal disomy 15. Results are discussed in relation to previous self-injury body site findings and implications for the relevance of syndrome-specific behavioral phenotypes.

Self-injurious behaviour and body site preference.

Self-injury by people with intellectual disabilities is a highly problematic and damaging behaviour with profound implications for quality of life. To date, very little detailed descriptive information has been available on the distribution and location of body sites that are injured. This study presents preliminary information on the locations of the self-injury body sites of 29 school-age individuals with developmental and intellectual disabilities who self-injured daily. Teaching staff in school-based special education programmes independently recorded the body locations of where their student's self-injured. Approximately 80% of the reported self-injury was directed disproportionately toward the head and hands. Three-quarters of head-directed self-injury was located on the front of the head, and 83% of hand-directed self-injury was located on the back of the hands. Furthermore, 32% of the body sites toward which self-injury was directed were located on stimulation-produced analgesia body sites. The implications of these findings are discussed in relation to the opioid hypothesis of self-injurious behaviour, and with regard to future research investigating functional diagnostic strategies considering both social and biological variables.