Introduction
Around 50% of autistic people experience levels of anxiety that affect their everyday lives, highlighting the need for effective treatments (Davis et al.
2011; Sterling et al.
2008; Mazefsky et al.
2008). Autistic individuals frequently present with multiple anxiety disorders concurrently, therefore treatments targeting underlying mechanisms may be most efficacious. A recent evidence-based theoretical framework to explain the mechanism that confers increased vulnerability to anxiety and to inform treatment in ASD has been proposed that includes intolerance of uncertainty as an important transdiagnostic mechanism (South and Rodgers
2017). The intolerance of uncertainty model of anxiety (Dugas et al.
1998) identifies IU as an assumption that uncertainty is stressful and upsetting and not knowing what is going to happen is negative and should be avoided at all costs. IU is considered to be a ‘broad dispositional risk factor for the development and maintenance of clinically significant anxiety’ (Carleton
2012). It involves the ‘tendency to react negatively on an emotional, cognitive, and behavioural level to uncertain situations and events’ (Buhr and Dugas
2009). Individuals who are intolerant of uncertainty find uncertain situations stressful and upsetting; have a tendency to interpret all ambiguous information as threatening and find it difficult to function in the face of uncertainty (Buhr and Dugas
2002,
2009; Laugesen et al.
2003). Indeed, uncertainty itself is perceived as threatening by people high in IU (Carleton
2012). IU has been linked to the development and maintenance of worry and Generalised Anxiety Disorder (GAD) (Buhr and Dugas
2006,
2009,
2012; Dugas et al.
1997,
2005; Freeston et al.
1994) and has also been proposed as a key underlying process in Obsessive Compulsive Disorder (OCD) (Holaway et al.
2006; Sookman and Pinard
2002; Tolin et al.
2003). More recently, IU has been linked to other disorders, including social anxiety disorder (Boelen and Reijntjes
2009; Carleton et al.
2010), panic disorder (Boswell et al.
2013) and anxiety sensitivity more generally (Carleton et al.
2007). IU is clearly important in the development and maintenance of anxiety in the general population.
Recently, research has begun to investigate the importance of IU to anxiety in Autism Spectrum Disorder (ASD). The concept resonates clinically with some of the core characteristics of ASD (Joyce et al.
2017; Rodgers et al.
2012; South and Rodgers
2017). Restricted and repetitive behaviours, such as insistence on sameness, inflexible adherence to routines and difficulty tolerating change have been linked with anxiety since the earliest descriptions of the disorder (Kanner
1943). These behaviours bear a conceptual resemblance to IU, with its associated avoidance of unexpected events and the desire to make life as predictable as possible (Rodgers et al.
2012). Evidence is now emerging that IU has a central role in the relationship between ASD and anxiety. Boulter et al. (
2014) modelled the relationship between anxiety and IU in an ASD group and a neurotypical comparison group. Results confirmed significant relationships between IU and anxiety in autistic children and were consistent with a causal model, suggesting that IU mediates the relationship between ASD and anxiety. Wigham et al. (
2015) examined the role that IU has in pathways between sensory processing difficulties, anxiety and restricted and repetitive behaviours (RRB) in ASD. These relationships were mediated by IU, indicating the important role IU may have in the interaction between anxiety and ASD traits. This is further supported by Neil et al. (
2016) who reported that IU is an important construct to explain the relationship between sensory sensitivities and anxiety in autistic children. Chamberlain et al. (
2013) report associations between shared neurobehavioral mechanisms in ASD and anxiety, indicating specific avenues for intervention targeting IU, and Maisel et al. (
2016) illustrate the role that IU has in anxiety in autistic adults.
In terms of assessment, Rodgers et al. (
2016b) developed and validated a child self and parent report measure of anxiety for autistic young people (the ASC-ASD). Using factor analytic techniques, the study identified four valid anxiety subscales, including an
uncertainty scale. Hodgsonet al. (
2017) undertook focus groups with parents of autistic young people exploring the concept of IU. Parents differentiated IU from dislike of change and from fear, discussed examples of IU and its impact on their children, and suggested that IU is a recognisable and important construct associated with anxiety that is distinguishable from but related to features of ASD. Kerns et al. (
2016) in a discussion of the differential diagnosis of anxiety disorders in autism report that
fears associated with uncertainty may be an important mechanism in the development and maintenance of anxiety in ASD. In conclusion, this evidence indicates that IU is an important mechanism in the development and maintenance of anxiety for autistic people and, as for neurotypical people (see Einstein
2014) an appropriate target for intervention.
The concept of IU has utility not only to theoretically inform understanding of factors underlying development and maintenance of anxiety, but has also been shown to be a beneficial target for treatment. Research has shown that experimental manipulation of intolerance of uncertainty can affect levels of worry in non-clinical neurotypical participants (Ladouceur et al.
2000). Cognitive behavioural treatments for clinically anxious patients have been developed which emphasise treating the cognitive
process rather than the cognitive
content of anxiety, specifically by aiming to increase patient’s tolerance for uncertainty and thereby achieving more sustainable change (Wilkinson et al.
2011). Research has confirmed the utility of such CBT protocols in reducing anxiety both in individual (Dugas and Ladouceur
2000; Ladouceur et al.
2000) and group formats (Dugas et al.
2003). Case series have also demonstrated the successful use of this intervention with neurotypical children and adolescents (Leger et al.
2003; Payne et al.
2011).
A variety of cognitive behaviour therapy (CBT) based programmes for anxiety and ASD have been evaluated recently, mainly in children and adolescents (Chalfant et al.
2007; McConachie et al.
2014; White et al.
2009; Wood et al.
2009) and with variable evidence for their effectiveness. These intervention programmes using CBT approaches have been variously adapted to meet the needs and learning styles of people with ASD. However, the application of these techniques, driven by the increasing awareness of the mental health needs of this population, is in advance of clear understanding of the underlying mechanisms inherent in anxiety in ASD. There remains much still to be done to specify models of anxiety for ASD populations, to enable the development of more targeted and effective intervention programmes. Importantly, Keefer et al. (
2016) in a multisite manualised group intervention for autistic children with high anxiety in the USA demonstrated that high levels of pre-treatment IU significantly predicted poorer treatment response.
A parent based group intervention (CUES©: Coping with Uncertainty in Everyday Situations), aimed at providing parents of autistic children with effective strategies to reduce IU in their children in everyday situations has recently been developed and the intervention is reported to be acceptable and feasible to families (Rodgers et al.
2016a). However, there is a critical need to develop effective interventions specifically for autistic adults.
The aim of this study therefore was to adapt and provide a preliminary evaluation of the feasibility and acceptability of an adapted version of the CUES© intervention programme, aimed at reducing IU, to be delivered on an individual basis to autistic adults (CUES-A©).
Discussion
The aim of this study was to adapt and provide preliminary evaluation of the feasibility and acceptability of CUES-A©, delivered on an individual basis to autistic adults. Given the growing evidence base of the centrality of IU to anxiety in autistic people (Boulter et al.
2014; Chamberlain et al.
2013; Rodgers et al.
2016a,
b; Keefer et al.
2016; Wigham et al.
2015), coupled with the high prevalence of multiple anxiety disorders occurring concurrently in ASD, targeting important transdiagnostic mechanisms, such as IU, may have significant treatment utility. The study builds on previous work developing a parent mediated intervention for autistic children with high IU (Rodgers et al.
2016a). Using a collaborative approach with four autistic adults, we co-constructed and then delivered a manualised, eight session intervention (CUES-A©). Utilising a single case experimental design we collected individual data monitoring change within participants and comparison between phases in relation to an individualised target uncertain situation, alongside a number of standardised measures. We also assessed feasibility and acceptability of the programme by recording attendance and completion, and through an end of programme evaluation questionnaire and interview. Attendance and retention to the programme was excellent. None of the participants dropped out and all participants indicated that they would recommend CUES-A to other autistic adults. Participants provided a range of free text comments in relation to the programme and a sample of these are provided here (the full data set is available on request from the corresponding author). In sum, these data indicate that the participants valued the programme, recognised the role of IU in their lives and found the strategies helpful.
Of course, given the stage of this work in the research cycle, the primary focus was on feasibility and acceptability. More formal evaluation of efficacy is a task for future studies.
The data from the single case experimental design are worthy of consideration here. All participants were able to generate and operationalise a target uncertain situation that they wished to address. Interestingly, for three of the participants the target situation related directly to difficulties which may be associated with an autism diagnosis, including difficulties with social communication, theory of mind and sudden changes to routine/plans, perhaps highlighting the increased vulnerability to IU that may be present for autistic individuals as a consequence of the interaction between autistic traits and IU (Wigham et al.
2015). Our primary outcome variable was the participant’s confidence in tackling their target uncertain situation. As can be seen from Fig.
2, for three of the four participants confidence generally increased over the course of the programme; this was maintained at follow-up, despite increased exposure to uncertainty as a consequence of engagement in behavioural experiments in relation to uncertainty that are a feature of participation in the programme. For Participant 4 the picture is not so clear cut. Figure
2 does not highlight a clear confidence increase in tackling the target IU situation for this individual; however, the CUES-A programme came at a time of particularly elevated anxiety for this participant, as he re-enrolled at university with all of the social and environmental changes that that confers. He related that the intervention had come at the best time in some ways as he was going through such a big transition and change in his life. As such, whilst we were not able to detect significant changes in confidence in relation to the IU target situation, Participant 4 reports that the programme enabled him to cope with things he would not previously have been able to manage. These conclusions are further supported by the Tau-U Calculations reported in Table
2. Tau-U was first calculated for each participant and then an aggregate value was calculated, weighted by the length of the series. Although only two of the eight individual phase comparisons were significant (Participants 2 and 4) perhaps due to low power, when all data were combined, a significant increase in confidence ratings from Phase A to Phase B and from Phase B to Phase C was found.
We also collected data at three time points using a range of standardised measures. Of course, with a sample of four participants, group based quantitative analyses of these data would not be meaningful. Rather we calculated reliable and clinically significant change for each participant. Two participants presented with scores on the PHQ-9, which assesses depressive symptoms, indicating recovery at follow-up (Participants 2 and 3). Participant 1 had low scores at baseline on this measure (below clinical cut-off and remained stable). Changes in self-reported anxiety and IU scores are, of course, of particular interest given the target of the CUES-A programme. Two participants showed change on the anxiety measure the GAD-7. Participant 1 (who was below clinical cut-off at baseline) showed improvement at follow-up, and Participant 3 showed reliable and clinically significant change and would be considered recovered at follow-up. Three participants demonstrated change in relation to the intolerance of uncertainty self-report measure (IUS-12). Participants 1 and 2 were considered recovered, whilst Participant 3, although still above clinical cut-off was improved. Similarly, three participants demonstrated significant improvement on the stress scale of the DASS-21. There is an emerging literature and theoretical framework suggesting a putative relationship between IU and restricted and repetitive patterns of behaviour for autistic individuals, such that engagement in repetitive acts may represent an attempt to impose certainty in an uncertain world (See South and Rodgers
2017). Given this emergent work, we were interested to determine whether participation in CUES-A may impact on self-reported engagement in RRB amongst autistic adults. To this end participants completed the RBQ2A. Whilst there is no clinical cut-off for the RBQ2A, we can see from Table
3 that all four participant’s scores on the measure indicate reliable improvement (i.e. less engagement) in repetitive behaviours at follow-up. To our knowledge this is the first time that a reduction in core autism symptomatology has been reported in relation to mental health intervention.
The lack of longer term follow-up is of course of note and whilst beyond the scope and goals of the current project is a major limitation of the current study. Of course, what is needed to determine the effectiveness of CUES-A© is a fully powered trial with long-term follow up of both proximal as well as more distal outcomes (e.g. quality of life, social or family functioning), in order to determine the clinical impact of the programme. With this in mind it will be important for future trials to think very carefully about the nature and timing of outcome assessments, and to develop a valid behavioural measure of IU to reduce the reliance on questionnaire measures of IU.
In summary, the current study sought to take the first steps towards the development of an intervention programme for autistic adults, which focuses on an important transdiagnostic construct underlying anxiety, intolerance of uncertainty. This preliminary evaluation of the acceptability and feasibility of the novel CUES-A© programme indicates that the programme is feasible to deliver directly to autistic adults, and is acceptable and face valid, and our preliminary data indicate that CUES-A has promise as a method to enable autistic adults to tackle the everyday challenges conferred by high levels of intolerance of uncertainty.