577519 research-article2015
AUT0010.1177/1362361315577519AutismMagiati et al.
Original Article
Anxiety symptoms in young people with autism spectrum disorder attending special schools: Associations with gender, adaptive functioning and autism symptomatology
Autism 1–15 © The Author(s) 2015 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/1362361315577519 aut.sagepub.com
Iliana Magiati1, Clarissa Ong2, Xin Yi Lim1, Julianne Wen-Li Tan1, Amily Yi Lin Ong1, Ferninda Patrycia1, Daniel Shuen Sheng Fung2, Min Sung2, Kenneth K Poon3 and Patricia Howlin4,5
Abstract Anxiety-related problems are among the most frequently reported mental health difficulties in autism spectrum disorder. As most research has focused on clinical samples or high-functioning children with autism spectrum disorder, less is known about the factors associated with anxiety in community samples across the ability range. This cross-sectional study examined the association of gender, age, adaptive functioning and autism symptom severity with different caregiverreported anxiety symptoms. Participants were caregivers of 241 children (6–18 years old) with autism spectrum disorder attending special schools in Singapore. Measures included the Spence Children’s Anxiety Scale and assessments of overall emotional, behavioural and adaptive functioning. Caregivers reported more anxiety symptoms in total, but fewer social anxiety symptoms, than Spence Children’s Anxiety Scale Australian/Dutch norms. There were no gender differences. Variance in total anxiety scores was best explained by severity of repetitive speech/stereotyped behaviour symptoms, followed by adaptive functioning. Severity of repetitive speech/behaviour symptoms was a significant predictor of separation anxiety, generalized anxiety, panic/agoraphobia and obsessive–compulsive subscale symptoms, but not of social phobia and physical injury fears. Adaptive functioning and chronological age predicted social phobia and generalized anxiety symptoms only. Severity of social/communication autism symptoms did not explain any anxiety symptoms, when the other variables were controlled for. Findings are discussed in relation to the existing literature. Limitations and possible implications for prevention, assessment and intervention are also discussed. Keywords adolescents, anxiety, autism spectrum disorder, children, correlates, predictors
Introduction Although core social, communication and behavioural impairments in autism spectrum disorder (ASD) have been extensively studied (e.g. Kuenssberg et al., 2011; Mazurek et al., 2012), co-occurring psychopathology and mental health problems have, until recently, been less well researched (for a recent review, see Mannion et al., 2014). Anxietyrelated concerns are among the most common mental health problems in ASD (Ghaziuddin, 2002; Wood and Gadow, 2010). Depending on the informant, methodology or sample employed, between 11% and 84% of children with ASD experience anxiety difficulties (White et al., 2009) and up to 40% are diagnosed with at least one Diagnostic and Statistical Manual of Mental Disorders (DSM) anxiety
disorder at some point in their lives (Van Steensel et al., 2011), compared with rates of 3%–24% in typically developing children (i.e. Cartwright-Hatton et al., 2006).
1National
University of Singapore, Singapore of Mental Health, Singapore 3National Institute of Education, Nanyang Technological University, Singapore 4Institute of Psychiatry, UK 5Faculty of Health Sciences, University of Sydney, Australia 2Institute
Corresponding author: Iliana Magiati, Department of Psychology, National University of Singapore, 02-24, 9 Arts Link, 117570 Singapore. Email: [email protected]
Downloaded from aut.sagepub.com at Stockholm University Library on November 18, 2015
2
Autism
It has been suggested that ASD impairments may, to some extent, contribute to increased stress due to perspective-taking and communication difficulties, limited flexibility and sensory sensitivities (Kerns and Kendall, 2012; Wood and Gadow, 2010). In turn, increases in stereotyped and challenging behaviours could be a consequence of efforts to reduce high levels of anxiety-related arousal (see also Hallett et al., 2013b; Ozsivadjian et al., 2012). Although these hypotheses remain to be adequately tested in prospective longitudinal studies, many different factors likely influence anxiety in this population. However, data on rates and types of anxiety disorders in ASD have largely been derived from clinical samples of individuals with ASD without associated intellectual disability (e.g. Kuusikko et al., 2008; Renno and Wood, 2013; White et al., 2015; see MacNeil et al. (2009) and Van Steensel et al. (2011) for reviews), thus limiting our understanding of the possible influences of factors such as level of intellectual or adaptive functioning or autism severity. In the section below, we examine the existing literature on the association between child characteristics and anxiety in ASD, with a specific focus on the relationships between child characteristics and different anxiety subtypes (i.e. social, generalized, obsessive–compulsive disorder (OCD), etc.).
Factors associated with anxiety in ASD Gender. In most of the published research on anxiety in ASD, it has not been possible to examine gender differences, as too few females have been involved. Among the few studies that have explored this issue, no gender differences have been consistently identified (see Kirkovski et al. (2013) for review). Moreover, very few, if any, studies have explored the possible relationship between gender and different forms of anxiety symptoms. Chronological age. Some studies have reported more anxiety symptoms in older as compared to younger children with ASD (Kuusikko et al., 2008; Lecavalier, 2006; Mayes et al., 2011b; Vasa et al., 2013); others have not identified any age effects (Farrugia and Hudson, 2006; Hallett et al., 2013; Pearson et al., 2006; Sukhodolsky et al., 2008). However, it is possible that the relationship with age may depend on the types of anxiety presentations studied. For example, in their meta-analysis, Van Steensel et al. (2011) noted that overall anxiety and generalized anxiety disorder (GAD) rates were higher among older children with ASD; separation anxiety disorder and OCD were more common in younger children. Intellectual/adaptive functioning level. Although significant positive associations between intellectual ability/adaptive functioning and increased anxiety symptoms have been reported in a number of studies (Davis et al., 2008; Hallett et al., 2013a; Lecavalier, 2006; Mayes et al., 2011b;
Niditch et al., 2012), others have identified no consistent relationships (i.e. Brereton et al., 2006; Simonoff et al., 2008). Kerns and Kendall (2012) proposed that intellectual abilities may be associated with specific types of anxiety symptoms in ASD but, to our knowledge, Sukhodolsky et al. (2008) and Hallett et al. (2013b) are the only groups to have examined the relationship between cognitive/adaptive functioning and different types of anxiety symptoms. Sukhodolsky and colleagues found that youth with IQ >70 were more likely to present with clinically elevated generalized, separation and somatization anxiety symptoms than their peers with IQ 70 who are considered to be cognitively able to access the mainstream curriculum in a supportive educational setting; and the other two (N = 61) cater for children with multiple disabilities, including ASD (nine participants did not state which school their child attended).
Measures Spence Children’s Anxiety Scale–Parent Version. This is a 38-item caregiver-rated measure of anxiety symptoms (higher scores = >anxiety) (Spence, 1999). It provides a
Downloaded from aut.sagepub.com at Stockholm University Library on November 18, 2015
4
Autism
Table 1. Caregiver-reported participants’ characteristics (N = 241 unless otherwise indicated). Participants’ characteristics
N (%) or mean (SD)/range
Chronological age
10 years 4 months (36 months)/5.7–17.6 years
Gender 197 (81.7%) Male Female 44 (18.3%) Ethnicitya Chinese 185 (76.8%) Malay 23 (9.5%) Indian 17 (7.1%) Other 14 (5.8%) Not reported/missing 2 (0.8%) Family Living with both parents 184 (76.3%) Living with one parent 20 (8.3%) Living with both parents and 33 (13.7%) extended family Not reported/missing 4 (1.7%) Caregiver-reported diagnosis of ASD Autism/autistic disorder/ASD 221 (91.7%) Asperger syndrome 15 (6.2%) PDD-NOS 5 (2.1%) Caregiver-reported other comorbid conditions ADHD 24 (10%) Medical conditions (i.e. 13 (5.4%) epilepsy, tuberculosis, Fragile X, etc.) Dyspraxia, dyslexia, SLD, SLI 16 (6.6%) Other (i.e. visual impairment, 10 (4.1%) auditory processing disorder, etc.) Caregiver-reported history of diagnosed anxiety disorder Yes (past/present) 16 (6.6%) No 216 (90%) Not reported/missing 9 (3.7%) SD: standard deviation; ASD: autism spectrum disorder; PDD-NOS: pervasive developmental disorder–not otherwise specified; ADHD: attention deficit hyperactivity disorder; SLD: specific learning difficulties; SLI: specific learning impairment. aEthnic group membership percentages are comparable to the country’s multi-ethnic composition rates.
total (range 0–114) and six DSM-IV-based subscale scores for generalized anxiety (range 0–18), social phobia (0–18), separation anxiety (0–18), panic attack and agoraphobia (0–27), OCD (0–18) and physical injury fears (0–15). Spence Children’s Anxiety Scale–Parent Version (SCASP) Australian/Dutch norms have been established by Nauta et al. (2004) based on a sample of 261 parents (45% Dutch) = 11.5 years, of 6- to 18-year-old children (mean age SD = 2; 48% boys) from rural and urban schools. A cut-off of 1 SD above the normative mean is being used to indicate clinically elevated anxiety symptoms (Spence, October 2012, personal communication). The SCAS-P has strong
psychometric properties in Australia and Hong Kong Chinese community samples (Li et al., 2011; Nauta et al., 2004); it has been frequently used in studies of children with ASD (see Grondhuis and Aman (2012) for review), and good construct, convergent and discriminant validity and moderate caregiver–child agreement have been reported with youth with ASD (Magiati et al., 2014; Russell and Sofronoff, 2005; Zainal et al., 2014). However, there are no normative data for the SCAS-P currently in Singapore. Developmental Behaviour Checklist, Parent Version, Second Edition. The Developmental Behaviour Checklist, Parent Version, Second Edition (DBC-P) is a 96-item checklist of emotional and behavioural problems for 4-to-18-year-old children with developmental and intellectual disabilities (Einfeld and Tonge, 2002). It provides a Total Behaviour Problem Score (TBPS; range 0–192; Cronbach’s α = 0.94 in this study) and six subscale scores (Disruptive, Antisocial, Self-absorbed, Communication Disturbance, Anxiety, Social Relating, higher scores = >problems). The 9-item DBC-P Anxiety subscale (raw score range: 0–18; α = 0.66 in DBC manual and 0.67 in this study) was used as an additional measure of anxiety symptoms. It correlates highly with the State-Trait Anxiety Inventory for Children (STAI-C; r = 0.61; Spielberger et al., 1983). A factor analysis derived DBC-Autism Screening Algorithm (ASA) comprising 29 DBC items discriminates well between children with intellectual/developmental disabilities with and without autism with a cut-off of 14 (Steinhausen and Metzke, 2004) or 17 (Brereton et al., 2002). In the present sample, 68% obtained a score ⩾14; when only participants with adaptive functioning standard scores
AUT0010.1177/1362361315577519AutismMagiati et al.
Original Article
Anxiety symptoms in young people with autism spectrum disorder attending special schools: Associations with gender, adaptive functioning and autism symptomatology
Autism 1–15 © The Author(s) 2015 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/1362361315577519 aut.sagepub.com
Iliana Magiati1, Clarissa Ong2, Xin Yi Lim1, Julianne Wen-Li Tan1, Amily Yi Lin Ong1, Ferninda Patrycia1, Daniel Shuen Sheng Fung2, Min Sung2, Kenneth K Poon3 and Patricia Howlin4,5
Abstract Anxiety-related problems are among the most frequently reported mental health difficulties in autism spectrum disorder. As most research has focused on clinical samples or high-functioning children with autism spectrum disorder, less is known about the factors associated with anxiety in community samples across the ability range. This cross-sectional study examined the association of gender, age, adaptive functioning and autism symptom severity with different caregiverreported anxiety symptoms. Participants were caregivers of 241 children (6–18 years old) with autism spectrum disorder attending special schools in Singapore. Measures included the Spence Children’s Anxiety Scale and assessments of overall emotional, behavioural and adaptive functioning. Caregivers reported more anxiety symptoms in total, but fewer social anxiety symptoms, than Spence Children’s Anxiety Scale Australian/Dutch norms. There were no gender differences. Variance in total anxiety scores was best explained by severity of repetitive speech/stereotyped behaviour symptoms, followed by adaptive functioning. Severity of repetitive speech/behaviour symptoms was a significant predictor of separation anxiety, generalized anxiety, panic/agoraphobia and obsessive–compulsive subscale symptoms, but not of social phobia and physical injury fears. Adaptive functioning and chronological age predicted social phobia and generalized anxiety symptoms only. Severity of social/communication autism symptoms did not explain any anxiety symptoms, when the other variables were controlled for. Findings are discussed in relation to the existing literature. Limitations and possible implications for prevention, assessment and intervention are also discussed. Keywords adolescents, anxiety, autism spectrum disorder, children, correlates, predictors
Introduction Although core social, communication and behavioural impairments in autism spectrum disorder (ASD) have been extensively studied (e.g. Kuenssberg et al., 2011; Mazurek et al., 2012), co-occurring psychopathology and mental health problems have, until recently, been less well researched (for a recent review, see Mannion et al., 2014). Anxietyrelated concerns are among the most common mental health problems in ASD (Ghaziuddin, 2002; Wood and Gadow, 2010). Depending on the informant, methodology or sample employed, between 11% and 84% of children with ASD experience anxiety difficulties (White et al., 2009) and up to 40% are diagnosed with at least one Diagnostic and Statistical Manual of Mental Disorders (DSM) anxiety
disorder at some point in their lives (Van Steensel et al., 2011), compared with rates of 3%–24% in typically developing children (i.e. Cartwright-Hatton et al., 2006).
1National
University of Singapore, Singapore of Mental Health, Singapore 3National Institute of Education, Nanyang Technological University, Singapore 4Institute of Psychiatry, UK 5Faculty of Health Sciences, University of Sydney, Australia 2Institute
Corresponding author: Iliana Magiati, Department of Psychology, National University of Singapore, 02-24, 9 Arts Link, 117570 Singapore. Email: [email protected]
Downloaded from aut.sagepub.com at Stockholm University Library on November 18, 2015
2
Autism
It has been suggested that ASD impairments may, to some extent, contribute to increased stress due to perspective-taking and communication difficulties, limited flexibility and sensory sensitivities (Kerns and Kendall, 2012; Wood and Gadow, 2010). In turn, increases in stereotyped and challenging behaviours could be a consequence of efforts to reduce high levels of anxiety-related arousal (see also Hallett et al., 2013b; Ozsivadjian et al., 2012). Although these hypotheses remain to be adequately tested in prospective longitudinal studies, many different factors likely influence anxiety in this population. However, data on rates and types of anxiety disorders in ASD have largely been derived from clinical samples of individuals with ASD without associated intellectual disability (e.g. Kuusikko et al., 2008; Renno and Wood, 2013; White et al., 2015; see MacNeil et al. (2009) and Van Steensel et al. (2011) for reviews), thus limiting our understanding of the possible influences of factors such as level of intellectual or adaptive functioning or autism severity. In the section below, we examine the existing literature on the association between child characteristics and anxiety in ASD, with a specific focus on the relationships between child characteristics and different anxiety subtypes (i.e. social, generalized, obsessive–compulsive disorder (OCD), etc.).
Factors associated with anxiety in ASD Gender. In most of the published research on anxiety in ASD, it has not been possible to examine gender differences, as too few females have been involved. Among the few studies that have explored this issue, no gender differences have been consistently identified (see Kirkovski et al. (2013) for review). Moreover, very few, if any, studies have explored the possible relationship between gender and different forms of anxiety symptoms. Chronological age. Some studies have reported more anxiety symptoms in older as compared to younger children with ASD (Kuusikko et al., 2008; Lecavalier, 2006; Mayes et al., 2011b; Vasa et al., 2013); others have not identified any age effects (Farrugia and Hudson, 2006; Hallett et al., 2013; Pearson et al., 2006; Sukhodolsky et al., 2008). However, it is possible that the relationship with age may depend on the types of anxiety presentations studied. For example, in their meta-analysis, Van Steensel et al. (2011) noted that overall anxiety and generalized anxiety disorder (GAD) rates were higher among older children with ASD; separation anxiety disorder and OCD were more common in younger children. Intellectual/adaptive functioning level. Although significant positive associations between intellectual ability/adaptive functioning and increased anxiety symptoms have been reported in a number of studies (Davis et al., 2008; Hallett et al., 2013a; Lecavalier, 2006; Mayes et al., 2011b;
Niditch et al., 2012), others have identified no consistent relationships (i.e. Brereton et al., 2006; Simonoff et al., 2008). Kerns and Kendall (2012) proposed that intellectual abilities may be associated with specific types of anxiety symptoms in ASD but, to our knowledge, Sukhodolsky et al. (2008) and Hallett et al. (2013b) are the only groups to have examined the relationship between cognitive/adaptive functioning and different types of anxiety symptoms. Sukhodolsky and colleagues found that youth with IQ >70 were more likely to present with clinically elevated generalized, separation and somatization anxiety symptoms than their peers with IQ 70 who are considered to be cognitively able to access the mainstream curriculum in a supportive educational setting; and the other two (N = 61) cater for children with multiple disabilities, including ASD (nine participants did not state which school their child attended).
Measures Spence Children’s Anxiety Scale–Parent Version. This is a 38-item caregiver-rated measure of anxiety symptoms (higher scores = >anxiety) (Spence, 1999). It provides a
Downloaded from aut.sagepub.com at Stockholm University Library on November 18, 2015
4
Autism
Table 1. Caregiver-reported participants’ characteristics (N = 241 unless otherwise indicated). Participants’ characteristics
N (%) or mean (SD)/range
Chronological age
10 years 4 months (36 months)/5.7–17.6 years
Gender 197 (81.7%) Male Female 44 (18.3%) Ethnicitya Chinese 185 (76.8%) Malay 23 (9.5%) Indian 17 (7.1%) Other 14 (5.8%) Not reported/missing 2 (0.8%) Family Living with both parents 184 (76.3%) Living with one parent 20 (8.3%) Living with both parents and 33 (13.7%) extended family Not reported/missing 4 (1.7%) Caregiver-reported diagnosis of ASD Autism/autistic disorder/ASD 221 (91.7%) Asperger syndrome 15 (6.2%) PDD-NOS 5 (2.1%) Caregiver-reported other comorbid conditions ADHD 24 (10%) Medical conditions (i.e. 13 (5.4%) epilepsy, tuberculosis, Fragile X, etc.) Dyspraxia, dyslexia, SLD, SLI 16 (6.6%) Other (i.e. visual impairment, 10 (4.1%) auditory processing disorder, etc.) Caregiver-reported history of diagnosed anxiety disorder Yes (past/present) 16 (6.6%) No 216 (90%) Not reported/missing 9 (3.7%) SD: standard deviation; ASD: autism spectrum disorder; PDD-NOS: pervasive developmental disorder–not otherwise specified; ADHD: attention deficit hyperactivity disorder; SLD: specific learning difficulties; SLI: specific learning impairment. aEthnic group membership percentages are comparable to the country’s multi-ethnic composition rates.
total (range 0–114) and six DSM-IV-based subscale scores for generalized anxiety (range 0–18), social phobia (0–18), separation anxiety (0–18), panic attack and agoraphobia (0–27), OCD (0–18) and physical injury fears (0–15). Spence Children’s Anxiety Scale–Parent Version (SCASP) Australian/Dutch norms have been established by Nauta et al. (2004) based on a sample of 261 parents (45% Dutch) = 11.5 years, of 6- to 18-year-old children (mean age SD = 2; 48% boys) from rural and urban schools. A cut-off of 1 SD above the normative mean is being used to indicate clinically elevated anxiety symptoms (Spence, October 2012, personal communication). The SCAS-P has strong
psychometric properties in Australia and Hong Kong Chinese community samples (Li et al., 2011; Nauta et al., 2004); it has been frequently used in studies of children with ASD (see Grondhuis and Aman (2012) for review), and good construct, convergent and discriminant validity and moderate caregiver–child agreement have been reported with youth with ASD (Magiati et al., 2014; Russell and Sofronoff, 2005; Zainal et al., 2014). However, there are no normative data for the SCAS-P currently in Singapore. Developmental Behaviour Checklist, Parent Version, Second Edition. The Developmental Behaviour Checklist, Parent Version, Second Edition (DBC-P) is a 96-item checklist of emotional and behavioural problems for 4-to-18-year-old children with developmental and intellectual disabilities (Einfeld and Tonge, 2002). It provides a Total Behaviour Problem Score (TBPS; range 0–192; Cronbach’s α = 0.94 in this study) and six subscale scores (Disruptive, Antisocial, Self-absorbed, Communication Disturbance, Anxiety, Social Relating, higher scores = >problems). The 9-item DBC-P Anxiety subscale (raw score range: 0–18; α = 0.66 in DBC manual and 0.67 in this study) was used as an additional measure of anxiety symptoms. It correlates highly with the State-Trait Anxiety Inventory for Children (STAI-C; r = 0.61; Spielberger et al., 1983). A factor analysis derived DBC-Autism Screening Algorithm (ASA) comprising 29 DBC items discriminates well between children with intellectual/developmental disabilities with and without autism with a cut-off of 14 (Steinhausen and Metzke, 2004) or 17 (Brereton et al., 2002). In the present sample, 68% obtained a score ⩾14; when only participants with adaptive functioning standard scores
