Egyptian Journal of Psychiatry

ORIGINAL ARTICLE
Year
: 2022  |  Volume : 43  |  Issue : 1  |  Page : 14--22

Short sensory profile and its relation with repetitive behavior and anxiety symptoms in children with autistic spectrum disorder


Heba E Abou El Wafa, Soha A El Latif Ghobashy, Amira K Zakaria 
 Department of Psychiatry, Alexandria University, Alexandria, Egypt

Correspondence Address:
MD Heba E Abou El Wafa
Department of Psychiatry, Alexandria University, Alexandria
Egypt

Abstract

Background Sensory processing abnormalities have been reported in 42%–88% of children with autism. Atypical sensory features are thought to result from aberrant sensory processing, and may be evident across all sensory modalities, including auditory, tactile, vestibular, oral, olfactory, movement, and visual domains. Several studies have shown a high prevalence of anxiety in autistic children, although they have difficulties expressing their emotions. In this study, the relation between abnormal sensory profile, repetitive behavior, and anxiety symptoms in children with autism spectrum disorder (ASD) will be elucidated. Results Those with the definite difference in short sensory profile (SSP) represented 63.3% of the cases. As for the SSP domains, Under-responsiveness/Seeks sensation was the domain with the highest percentage of those with the definite difference (65%) followed by Auditory sensitivity (46.7%) and then Low energy (40%), whereas Visual/Auditory sensitivity was the domain with least cases showing definite difference (11.7%). Sensory abnormality is more evident in older children. Autism severity is related to the severity of the sensory abnormality. The total score of SSP showed a significant correlation with the total Repetitive Behavior Scale-Revised score. Anxiety Scale for Children with Autism Spectrum Disorder − Parent Version showed a significant correlation with the total score of SSP. Conclusion Sensory processing abnormalities are common among children with ASD and it is related to the severity of ASD, repetitive behaviors, and anxiety symptoms. Therefore, using these scales for individualization of the characteristics of sensory profile and their behavioral response and anxiety symptoms in basic assessment and follow-up is recommended, as well as promoting changes in therapeutic intervention through the possibility of choosing and designing the most appropriate intervention based on the individualized profile of the patients.



How to cite this article:
Abou El Wafa HE, El Latif Ghobashy SA, Zakaria AK. Short sensory profile and its relation with repetitive behavior and anxiety symptoms in children with autistic spectrum disorder.Egypt J Psychiatr 2022;43:14-22


How to cite this URL:
Abou El Wafa HE, El Latif Ghobashy SA, Zakaria AK. Short sensory profile and its relation with repetitive behavior and anxiety symptoms in children with autistic spectrum disorder. Egypt J Psychiatr [serial online] 2022 [cited 2022 Jul 7 ];43:14-22
Available from: http://new.ejpsy.eg.net/text.asp?2022/43/1/14/338554


Full Text



 Background



Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by social interaction impairment, repetitive behavior, and sensory abnormalities (Geschwind, 2009; Silver and Rapin, 2012).

The clinical phenotype of ASD can present in a variety of combinations that can range from a nonverbal child with mental retardation to those who possess a superior intelligence quotient (IQ) with inadequate social skills (Gadad et al., 2013; Masi et al., 2017).

Atypical sensory features that have been reported in 42%–88% of children with the disorder are thought to result from aberrant sensory processing, and may be evident across all sensory modalities , with specific affection of the tactile and taste/smell sensitivity, the auditory filtering and the sensory seeking (Tomchek and Dunn, 2007; Brock et al., 2012) (Watling et al., 2001).

Repetitive and restricted behaviors (RRB) represent a common problem in ASD, where they constitute the second dimension of diagnostic criteria (Matuschek et al., 2016).

Children with autism have difficulties in communicating their emotions; however, several studies have shown a high prevalence of anxiety in those participants. Among the functions hypothesized for RRB, they are thought to be coping strategies that allow autistic participants to avoid or reduce the high level of anxiety resulting from being overwhelmed by the surrounding environment (van Steensel et al., 2011; Gaye Ambler et al., 2015).

A high rate of sensory processing difficulties exists in children with ASD who have more sensory-related behavioral symptoms than typically developing controls. Classification of sensory processing difficulties has been proposed by the Interdisciplinary Council on Developmental and Learning Disorders (ICDL Work Groups, (2005)). ICDL proposed that it can be classified into: (a) sensory over-responsivity; (b) sensory under-responsivity; and (c) sensory seeking (Burns et al., 2017).

The relation between abnormal sensory profile, repetitive behavior, and anxiety symptoms in children with ASD remains to be elucidated. Therefore, we set this study to clarify such relation in Egyptian children with ASD.

 Method



A cross-sectional survey design was used on a selected sample of 60 children with ASD recruited from Child and Adolescent Psychiatry Clinic at El-Hadara University Hospital and Mamoura Psychiatric Hospital over a period of one and a half year from 2018 to 2019. Ethical approval from the institutional ethics committee and verbal consent from parents and/or caregivers of all the participants were obtained.

All cases were subjected to the following:History taking.Full psychiatric interview using the Kiddie Schedule for Affective Disorders and Schizophrenia-Present and Lifetime Version 2013 (Advanced Center for Intervention and Services Research ACISR, 2016).Thorough clinical examination with emphasis on neurological examination.Short sensory profile (SSP), a standardized parent questionnaire that measures children’s responses to sensory events in everyday life (McIntoshet al., 1999).The Repetitive Behavior Scale-Revised (RBS-R) (Lam and Aman, 2007).Anxiety Scale for Children with Autism Spectrum Disorder (ASC-ASD) Arabic − Parent Version (Rodgerset al., 2016).Childhood Autism Rating Scale (CARS-2): the standardized Arabic edition for an established assessment for ASD among Arabic-speaking children (Akoury-Diraniet al., 2013).

 Results



Short sensory profile (SSP) aspects

The total score mean was 135.9±18.76 (i.e., in the range of definite sensory impairment). Those with “Definite difference” in sensory processing represented 63.3% of the cases, 23.3% were having a “Probable difference,” and 13.3% had a “Typical performance.”

As for the domains, [Figure 1] shows that Under-responsiveness/Seeks sensation was the domain with the highest percentage of those with the definite difference in 40 cases (65%) followed by Auditory filtering domain in 28 cases (46.7%) and then Low energy in 24 cases (40%), Taste/smell sensitivity in 20 cases (33.3%), Tactile sensitivity in 19 cases (31.7%), whereas Visual sensitivity was the domain with least cases showing the definite difference in 7 cases (11.7%).{Figure 1}

Repetitive Behavior Scale-Revised (RBS-R)

For the RBS-R, the total score for the cases showed a mean of 32.62±18.80. All the cases showed at least one form of repetitive behavior at the time of assessment.

Anxiety Scale for Children with Autism Spectrum Disorder Arabic − Parent Version (ASC-ASD-P)

Parent version of the ASC-ASD scores had a mean of 15.62. Only 30% of the studied sample showed significant anxiety scores (score ≥20) ([Table 1]).{Table 1}

The age of the child at the time of assessment showed a significant negative correlation with SSP score (P=0.015) and significant positive correlations with both of RBS-R (P<0.001) and ASC-ASD-P (P=0.014) scores. Thus, with increasing age, the severity of the sensory abnormality, repetitive behavior, and anxiety symptoms increase ([Table 2]).{Table 2}

There was a statistically significant difference between the two groups according to SSP score (P=0.032), where the severe group had significantly lower scores, that is, the definite difference in sensory processing.

There is a significant negative correlation between the total score of SSP and CARS 2 (P value =0.001), total RBS-R (P value <0.001), and ASC-ASD-P Anxiety score (P value <0.001). Thus, the more severe ASD had a lower SSP score denoting a more definite difference in sensory processing. This also denotes that, with the severity of sensory impairment (lower SSP score), the repetitive behavior and anxiety symptoms are more frequent.

Also, [Table 3] shows that there was a statistically significant positive correlation between RBS-R and ASC-ASD-P score (P value <0.001) ([Table 4]).{Table 3}{Table 4}

A multivariate regression analysis that included all parameters with significant univariate correlations showed that sensory impairment (lower SSP score) was mostly associated with the severity of ASD (CARS-2 score) ([Table 5]).{Table 5}

The higher RBS-R was associated with the higher anxiety score ASC-ASD-P (P<0.001) and older age (P=0.012) ([Table 6]).{Table 6}

As for the ASC-ASD-P score, the most significant correlation was that with the RBS-R (P<0.001).

 Discussion



The purpose of the present study was to investigate the relation between sensory characteristics, repetitive behavior, and anxiety symptoms on a sample of 60 children with ASD measured with the SSP (McIntosh et al., 1999) RBS-R, and ASC-ASD-P (Rodgers et al., 2016). The severity of the disorder was measured by CARS2 (Akoury-Dirani et al., 2013).

Sensory processing and autism severity

Although the measurement instruments used to evaluate the severity of the disorder have been quite varied among previous studies, most of them found that severity is directly related to the degree of sensory impairments (Henshall, 2008). Studies have reported associations between overall autism severity and the presence of more sensory problems (Ben-Sasson et al., 2008). Using the CARS as a measure of autism severity, Kern et al. (2006) found that total sensory profile scores correlated with autism severity in children with autism (Watson et al., 2011). Our study results came in concordance with previous ones, where the sensory profile showed a significantly lower score in the severe group (P=0.032).

This is clarified in the effect of sensory processing on core autism symptoms. In a matter of fact, in confirmation of the importance of the role played by the sensory aspects even in the diagnosis, the fifth edition of the DSM, among the criteria for ASD, includes atypical sensory behaviors, thus introducing the “hyper- or hypo-reactivity to sensory input or unusual interest in sensory aspects of environment” (American Psychiatric Association APA, 2013). This role of sensory processing has been investigated in scarce yet elaborative studies on the neurobiological bases of sensory processing in ASD using functional MRI and electrophysiological and behavioral data (Gomot et al., 2002). It was also explained by Dunn (1997) in his proposed sensory processing model that was similar to another proposal by ICDL workgroups in 2005 (Greenspan and Wieder, 2008).

Results of SSP from the current study showed that those with “Definite difference” in sensory processing represented 63.3% of the cases, 23.3% were having a “Probable difference,” and 13.3% had a “Typical performance.” Notably, when probable and definite difference classifications were summed as an indicator of some degree of sensory processing differences, 86.6% of the sample of children with ASD was rated as having some degree of difference in sensory processing based on the SSP total score.

These results coincided with many previous research works that reported sensory processing abnormalities in 42%–88% of children with autism disorder. In a study with similar results, overall SSP results showed that most participants in this sample (82%) exhibited some degree of sensory processing difficulty (Baker et al., 2007). It is assumed that atypical sensory features are thought to result from aberrant sensory processing, and may be evident across all sensory spectrum (Brock et al., 2012).

Sensory profile distribution

In the current study, the SSP showed that Under-responsiveness/Seeks sensation was the domain with the highest percentage of those with the definite difference (65%) followed by Auditory filtering domain (46.7%), and then Low energy (40%), Taste/smell sensitivity (33.3%), and Tactile sensitivity (31.7%), whereas Visual/Auditory sensitivity was the domain with least cases showing definite difference (11.7%).

It agrees with the sensory processing sections of the SSP done by Tomchek and Dunn (2007) demonstrating that the highest reported definite differences in the ASD group included Under-responsiveness/Seeks sensation (86.1%), Auditory filtering (77.6%), Tactile sensitivity (60.9%), and Taste/smell sensitivity (54.1%).

These findings are in contrast to the Ermer and Dunn (1998) study where a low incidence of behaviors was reported within the sensory seeking. The difference between our results and this study could be attributed to different age groups as the patterns of the sensory abnormalities in children with autism are pervasive and multimodal and may change across age (Rogers and Ozonoff, 2006).

Similar to our study, a study, examining the different types of sensory-processing issues with the SSP, found that children with ASD consistently showed more sensory atypicality compared with typically developed (TD) group across all modalities. However, the strongest group differences were noted in the Under-responsiveness/Seeks sensation and Auditory-filtering sections (Kojovic et al., 2019). Watling et al. (2001) reported affection of all sensory modalities with specific affection of the tactile and taste/smell sensitivity, the auditory filtering, and the sensory seeking.

In addition, other previous studies reported that more than 98% of the ASD sample had significant differences in the Under-responsiveness/Seeks Sensation section (Kern et al., 2006). Analysis of section items indicated that the sample appeared to seek sensory input from multiple sensory systems (e.g., auditory, vestibular, tactile, proprioception). The sensory processing findings noted in this study reflect a pattern of dysfunctional sensory modulation; that is, children with ASD demonstrate difficulty with filtering and changing to sensory stimuli to develop an adaptive response. Sensory modulation has been defined as the capacity to regulate and organize the degree, intensity, and nature of responses to sensory input in a graded and adaptive manner. This supports findings of previous research in this domain (Tomchek and Dunn, 2007).

In view of these evidence, the specificity of sensory problems in the population with autism usually does not take into consideration the fact that several studies have found that individuals with autism tended to show a mixed type of sensory responsiveness; in other words, an individual would show atypical scores across all sensory profile quadrants, that is, sensory hyper-, hypo-sensitivity, seeking, and avoidance (Baranek et al., 2006). It was hypothesized in previous research that, like repetitive behaviors, it is the frequency of sensory impairment rather than the systematic form that distinguishes individuals with autism from both typically developed individuals and other clinical groups (Uljarević, 2013).

Sensory processing and repetitive behaviors

In the present study, total SSP and RBS-R scores had a significant negative correlation, where repetitive and restricted behaviors are more severe in those with severe sensory dysfunction. These results are consistent with previous research describing the co-occurrence of repetitive behaviors and sensory response abnormalities in the ASD population (Uljarevic, 2013).

Di Renzo et al. (2017) studied the relation between sensory characteristics and repetitive behaviors using the same scales used in our studies on a sample of 50 preschoolers and their results were similar to ours.

Several other studies have addressed the relationship between sensory problems and repetitive behaviors. For example, Boyd et al. (2009) used RBS-R and Sensory Questionnaire to examine repetitive behaviors and sensory processing in 61 children with high functioning autism (HFA) aged 6–17 years with 64 typically developing children. Not surprisingly, children with HFA had more repetitive behaviors and sensory problems than individuals in the TD group (Uljarević, 2013).

Furthermore, a significant, positive association was found between the total repetitive behaviors scores and overall sensory problems, and this relationship remained significant after controlling for IQ. This was in studies by Boyd et al. (2009), Gabriels et al. (2013), and Chen et al. (2008).

It was hypothesized in literature that sensory problems are related to the stereotypic or repetitive behaviors displayed by children with ASD, and that the stereotypic behaviors reflect the child’s attempt to lower arousal (self-calm) or increase arousal (sensory-seeking) (Henshall, 2008; Posar and Visconti, 2018).

In other words, it was proposed that repetitive behaviors might function as a soothing or stimulating mechanism for children with sensory dysfunction and this explains their relation with the severity of the sensory abnormality (Jussila et al., 2020).

As for the relation between repetitive behaviors and severity of the disorder, RBS-R score was significantly related to CARS-2 score in our study. It coincides with many other studies investigating repetitive behaviors in children with ASD. This may reflect sound psychometric characteristics of both scales where their results about frequency and severity of a core feature of ASD correlated (Lam and Aman, 2007).

Repetitive behavior and anxiety

In previous studies, RRBs have been related to the presence of anxiety in individuals with ASD (Scahill et al., 2015).

In a previous study, 58% of children with severe restricted/repetitive behavior at enrollment had elevated anxiety symptoms by age 11, compared with 41% of those with moderate, and 20% of those with mild restricted/repetitive behavior, respectively. Moderate and severe restricted/repetitive behavior were both associated with increased odds of elevated anxiety (moderate aOR: 2.5 [1.2−5.3]; severe aOR: 3.2 [1.4−7.5]). They proposed that restricted/repetitive behavior severity at the time of ASD diagnosis indicates risk for future anxiety symptoms (Uljarević, 2013).

In cross-sectional samples, scores on anxiety measures and scores on repetitive behavior measures show low-to-moderate correlations (i.e., r=0.15–0.45). In other studies, this association appeared stronger (Scahill et al., 2015).

In our study, results showed a strong positive correlation between anxiety and repetitive behavior (r=0.644 and P value<0.001).

This could be explained by the hypothesis proposed in literature that RRBs are thought to be coping strategies that allow autistic participants to avoid or reduce the high level of anxiety resulting from being overwhelmed by the surrounding environment (van Steensel et al., 2011).

Anxiety in ASD and its relation with sensory processing

In the present study, 30% of the cases had significant anxiety symptoms based on ASC-ASD-P scores. Anxiety is a common co-occurring symptom in ASD. Studies report that between 22% and 84% of children are reported by parents to experience impairing anxiety (White et al., 2009).

In a meta-analysis, the prevalence of anxiety disorders (conceptualized as persistently elevated anxiety symptoms leading to significant distress or impairment) was estimated at 40% in ASD by middle childhood (van Steensel et al., 2011).

The extent to which anxiety disorder estimates in children with ASD are biased by the inconsistent differentiation of anxiety and ASD symptoms is unclear (Ginsburg et al., 2011).

This wide range could be explained by more than one factor. First, the fact that participants with ASD have difficulties in communicating their emotional states; however, several studies have shown a high prevalence of anxiety in those participants (Szatmari et al., 2006).

Second, as evidenced through the study of Kerns et al. (2014) who examined anxiety presentations in young people with ASD and concluded that there was evidence for varied manifestations of anxiety in ASD. In their sample, 17% of children presented with “traditional” anxiety, 15% presented with anxiety altered in its presentation by its interaction with ASD-related characteristics, and 31% presented with a combined profile (Kerns et al., 2014).

White et al. (2015) examined the metric and latent factor equivalence of the Multidimensional Anxiety Scale for Children across three groups: young people with an anxiety disorder, young people with ASD, and a healthy control group, and concluded that the factor structure was different in the ASD group, further supporting the notion of the varied manifestations of anxiety in ASD.

Lecavalier et al. (2014) systematically reviewed 10 anxiety measures for use in clinical trials in ASD and concluded that using measures developed for use with typically developing children “may be less than satisfactory” with children with ASD. This was a third explanation to the contradictory and very wide range of anxiety level in individuals with ASD reported in literature. What explains our results where only 30% had significant anxiety symptoms is that we used a scale that was adapted to be used for children with ASD, making the measurement more specific. Yet it was not that satisfactory with younger nonverbal children (Rodgers et al., 2016).

As for the relation with sensory abnormality in our study, the ASC-ASD-P score was significantly correlated with the SSP score (P<0.001). This was in agreement with many studies that reported that anxiety in ASD appears to be associated with sensory processing abnormalities (Green and Ben-Sasson, 2010).

To sum up, the causes of anxiety in ASD could be explained by having problems in understanding of emotional states and intentions of others, together with over-reaction and inability to block-out insignificant environmental sensory stimuli, so that individuals with autism might experience their world as highly unpredictable, making even the most simple situations and events uncertain and difficult (Magiati et al., 2017).

 Conclusion



We concluded from our study that sensory processing is common among children with ASD and is more evident in older ones. Furthermore, it is significantly related to the severity of ASD, repetitive behaviors, and anxiety symptoms. The use of sensory profile as a trait marker for autism is recommended as well as using these scales for individualization of the characteristics of sensory profile and the behavioral response and anxiety symptoms in basic assessment and follow-up. Finally, we promote changes in therapeutic intervention through the possibility of choosing and designing the most appropriate intervention based on the individualized profile of the child.

Aknoweldgements

The authors would like to express gratitude to the whole staff of Alexandria University Clinic for being cooperative with the research team.

Ethics approval and consent to participate

A verbal consent (as this is more preferred by our community and this was approved by the ethical committee) to participate in the study was obtained from parents of all children as well as approval of the current research from ethical committee of lexandria University (reference number is not applicable).

Consent for publications

All authors are accepting publications.

Availability of data and materials

All data were accessible by the internet as shown in details of references section.

Funding

This study was not funded by any organizations nor individuals.

Authors contributions

HA revised the work and she attributed to the conception of this work and interpretation of data. SG played an important role in the conception of this work and study design also in interpretation of data. AZ played a major role in the acquisition of data and drafted the work. All authors have read and approved the manuscript.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

Abbreviations: ASC-ASD-P, Anxiety scale for children with autism spectrum disorder – parent version; ASD, Autism Spectrum Disorder; CARS2, Childhood Autism Rating Scale, second edition; RBS-R, Repetitive Behavior Scale-Revised; RRB, Repetitive and restricted behaviors; SSP, Short Sensory Profile; TD, Typically Developing.

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