Autism Spectrum Disorder (ASD) is used to categorise a class of early-onset, neurodevelopmental disorders characterised by difficulties in social communication and interactions, and restricted or repetitive patterns of behaviour [1]. Across the Western world, ASD is currently estimated to be diagnosed in 1 in every 100–110 children [2, 3], although these rates vary due to differences in the availability of assessment services. For example, U.S. data from the ‘Centre for Disease Control and Prevention’ recently reported a rate of 1 in 54 [4]. The core symptoms of ASD are evidenced to continue across the lifespan [5, 6]. Despite the life-long impact of ASD, the research focus and delivery point of interventions to date have typically been restricted to early childhood and school-age years, followed by a “services cliff” post high-school [8, 9]. Research for evidenced-based interventions targeted to adults with ASD are only in the early stages of development, and support services are lacking. [10, 11].
Adults with ASD are at an increased risk of mental health problems, which have been found to be one of the strongest predictors of disability, quality of life reductions and difficulties in daily functioning [12]. Amongst psychiatric comorbidities, the most common is Social Anxiety Disorder (SAD), which occurs at a much higher rate in adults with ASD (50–70%) [13, 14] compared to the general population (7%) [1]. SAD is characterised by both persistent, intense fears of negative evaluations in social situations and social avoidance behaviours. The impact and experience of comorbid SAD in adults with ASD has also been captured through qualitative research; with one study participant describing social anxiety in the following way;
As the years pass, I suffer increasing anxiety for lack of even casual acceptance by my species and, conversely, huge spikes of anxiety when someone actually does ‘see’ me. Invisibility has become my comfort zone as well as my prison. [15] p. 481.
A bidirectional link between social anxiety and the key symptoms of ASD, particularly difficulties in social functioning and reciprocal social interactions, has been suggested as a primary contributor to the high co-occurrence of anxiety disorder in people with ASD [16]. That is, the difficulties with social interaction and communication commonly experienced by those with ASD may lead to an increased prevalence and severity of SAD, and, in turn, this elevated anxiety may further exacerbate pre-existing social deficits. Various factors have been identified for maintaining this bidirectional link between social anxiety and social functioning, including physiological arousal, intolerance of uncertainty, social withdrawal, and difficulties expressing and understanding emotion [17, 18]. Further, the peculiarity of special interests, repetitive behaviours and rigidity around routines can isolate people with ASD from their neurotypical peers [19, 20]. This has been found to increase rates of rejection and bullying, thus increasing the vulnerability of people with ASD to negative social experiences [21]. Sensory aversions to certain environments, sounds or lights can induce discomfort and further increase anticipatory anxiety or avoidance behaviours [20, 22]. Consistently, social skills deficits and social anxiety are strongly correlated in both children and adults with ASD [23, 24].
Despite the bidirectional relationship that has been demonstrated to exist between social anxiety and social functioning, anxiety interventions and social skills groups for ASD have predominantly been examined separately. In a recent review of literature, Balderaz (2020) identified six published studies that reported on Group Social Skills Interventions (GSSIs) for adults with ASD. Significant improvements in social functioning were found in four studies, however, across all studies the improvements in social functioning did not generalise to improvements in either social anxiety or general mental health [25]. One study however, reported contrasting findings, with participants displaying change in social anxiety, but no change in social functioning or general mental health (Spain et al., 2017) The lack of change on mood outcomes across GSSIs for adults with ASD is inconsistent with other literature demonstrating the efficacy of group interventions (especially CBT-based) in improving mental health outcomes for adults with SAD [7, 26]. An exception to this was a study that involved adults with ASD (aged 18–29) which reported increases in social functioning and significant small-to-medium treatment effects on mood upon completion of the intervention [27]. The reduction in mood symptoms was suggested to be due to positive social experiences and the support gained from the group intervention, though it remains unclear why this generalisation effect has not been observed in other group studies [27].
For interventions targeting anxiety disorders in ASD (including SAD), there is a small but promising body of emerging research demonstrating the efficacy of Cognitive-Behavioural Therapy (CBT) for both children and adults. A recent meta-analysis of 11 studies reported statistically significant improvements on clinician and informant-report measures of anxiety in response to CBT interventions [7]. While this meta-analysis only included two studies with adults, additional randomised-controlled trials have demonstrated the positive effects of CBT-based interventions for transdiagnostic anxiety disorders in adults with ASD [28, 29]. The majority of literature to date has focussed on adults with ASD without intellectual disability (ID). Within the broader scope of CBT studies, Weston et al (2016) found of the 24 studies evaluating CBT on various affective and ASD symptoms, the majority involved group interventions (15 in total). Other research has consistently indicated the benefits of group interventions for anxiety disorders generally, both as a cost-effective treatment intervention, but also given the group context provides a natural milieu for both exposure and skills practice [30]. Not surprisingly, these same advantages have been highlighted within GSSIs for people with ASD [31].
It has been widely accepted that all standard interventions (e.g. for SAD) require modifications in order to be effective for people with ASD. CBT for example, is generally reliant on effective reciprocal communication and awareness of one’s own thoughts and feelings, processes which are impaired in people with ASD [32, 33]. Hence, people with ASD require explicit and extensive training in these skills, which needs to be incorporated in interventions. For example, in line with the National Institute for Care and health Excellence (NICE) guidelines, a systematic review of effective modifications for CBT in children and adolescents with ASD reported the use of video-modelling, relaxation strategies, using concrete images, and involving a parent to support implementation as recommended modifications to interventions [34]. Further, experiences unique to ASD, such as being triggered by changes in routines, or sensory events (such as bright lights, or unusual noises) need to be included within both treatment interventions and assessment tools [35].
At present, there are only two published group intervention studies that target both social skills and social anxiety, and have been modified to suit ASD populations. Both studies, involved a combination of group and individual sessions. The first study used the Multimodal Anxiety and Social Skills Intervention (MASSI) and included seven group sessions and up to 13 individual sessions that incorporated parent education and training [36]. In the randomised control trial, 30 teenagers aged 12 to 17 years were recruited and assigned to either the MASSI intervention or a waitlist control group. Assessments were conducted pre- and post-intervention, with the MASSI showing a large, statistically significant treatment effect on social skills (indexed by the Social Responsiveness Scale; SRS-2) but no statistically significant effect for anxiety [36]. A small sample size was suggested as a potential reason for this.
The second group intervention study, the ‘Social Skills Intervention’ recruited 18 adult males aged 22 to 48, for a social skills/social anxiety group following a course of individual CBT [37]. The ‘Social Skills Intervention’ was an 11-week program that covered topics (through a CBT framework) including communication strengths and difficulties, types of relationships, goal setting, conversation skills and emotional awareness of self and others. The model of treatment utilised placed greater emphasis “on those interventions derived from cognitive principles”, while behavioural strategies like exposure were used to inform between-session tasks. Assessments were conducted pre- and post-intervention, with a medium effect size on self-reported social anxiety (indexed by the Leibowitz Social Anxiety Scale, Self-Report; LSAS-SR) but changes on measures of low mood, general anxiety and overall social functioning were not significant.
In joint social anxiety and social functioning interventions, the MASSI was found to significantly improve social functioning, while the Social Skills Intervention improved social anxiety but not mood or social functioning [36, 37]. To date, it is not known if equivalent treatment effects across both domains can be achieved through a stand-alone group intervention, and whether they can be achieved without the supplement of individual psychological sessions. The inclusion of individual psychotherapy has been identified as a potential limitation to generalisability and clinical utility in both studies. The purpose of the current study was to determine both the efficacy and tolerability of an adjusted CBT group intervention for young adults with ASD to reduce social anxiety symptoms and improve social functioning difficulties.
In line with research demonstrating the benefits of CBT programs in improving social anxiety (Spain et al. 2017) and social functioning (White et al., 2013), we hypothesised that the CBT group intervention would result in reductions on both the primary measures of social anxiety and social functioning deficits. Due to the mixed findings in the literature related to the effect of CBT group interventions on general mental health [27, 37], we made no specific hypotheses as to the impact of the intervention on mood or psychological distress.