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. 2019 Dec;23(68):1–94. doi: 10.3310/hta23680

Guided self-help for depression in autistic adults: the ADEPT feasibility RCT.

Ailsa Russell, Daisy Gaunt, Kate Cooper, Jeremy Horwood, Stephen Barton, Ian Ensum, Barry Ingham, Jeremy Parr, Chris Metcalfe, Dheeraj Rai, David Kessler, Nicola Wiles
PMCID: PMC6943380  PMID: 31856942

Abstract

BACKGROUND

Co-occurring depression frequently occurs in autism. Evidence-based psychological interventions have been successfully adapted to treat co-occurring anxiety, but there is little evidence about the usefulness of adapted cognitive-behavioural therapy for depression. To the authors' knowledge, to date there have been no randomised trials investigating the usefulness of low-intensity cognitive-behavioural therapy for depression in autism.

OBJECTIVES

The objectives of the study were to (1) develop a low-intensity psychological intervention for depression adapted for autism, (2) assess the feasibility and patient and therapist acceptability of the intervention, (3) estimate the rates of recruitment and retention for a full-scale randomised controlled trial and (4) identify an appropriate measure of depression to be used in a full-scale randomised controlled trial.

DESIGN

The study comprised a randomised controlled trial (n = 70) with a nested qualitative evaluation (n = 21). Seventy eligible and consenting participants were randomly allocated to guided self-help or to treatment as usual.

SETTING

Adult autism services in two NHS regions.

PARTICIPANTS

Adults with a diagnosis of autism spectrum disorder with depression, that is, a Patient Health Questionnaire-9 items score of ≥ 10. People who had attended more than six sessions of cognitive-behavioural therapy in the previous 6 months were excluded.

INTERVENTIONS

The low-intensity intervention (guided self-help) comprised materials for nine individual sessions, based on behavioural activation adapted for autism, facilitated by therapist guides (coaches) who were graduate-level psychologists who attended training and regular supervision. Treatment as usual was standard NHS care for depression.

MAIN OUTCOME MEASURES

Outcomes were measured 10, 16 and 24 weeks post randomisation using self-report and interview measures of depression, anxiety, obsessive-compulsive symptoms, social function and quality of life, and a health-care and service use questionnaire. As this was a feasibility study also designed to identify the most appropriate measure of depression, it was not possible to specify the primary outcome measure or outcome point a priori.

RESULTS

The aims of the study were met in full. The guided self-help intervention was feasible and well received by participants and coaches. The majority of allocated participants attended the intervention in full. The most practical outcome point was determined to be 16 weeks. There were differential rates of attrition across the treatment groups: 86% of the guided self-help group remained in the study at 24 weeks, compared with 54% of treatment as usual group. The qualitative study suggested that guided self-help had enhanced credibility with participants at the point of randomisation. Inter-rater reliability of the interview measure of depression was less than adequate, limiting the conclusions that can be drawn from the prespecified sensitivity to change analyses.

CONCLUSIONS

The intervention was feasible and well received. Although this feasibility study was not a fully powered trial, it provided some evidence that the guided self-help intervention was effective in reducing depressive symptoms. A full-scale clinical effectiveness and cost-effectiveness trial of the intervention is warranted.

FUTURE WORK

Improvements to the intervention materials as a result of qualitative interviews. Stakeholder consultation to consider future trial design, consider strategies to improve retention in a treatment as usual arm and select a self-report measure of depression to serve as the primary outcome measure.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN54650760.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 23, No. 68. See the NIHR Journals Library website for further project information. This study was also supported by the NIHR Biomedical Research Centre at the University Hospitals Bristol NHS Foundation Trust and the University of Bristol.

Plain language summary

The National Institute for Health Research commissioned research to investigate whether or not NHS psychological treatment for depression could be adapted for autistic people. Psychological treatment for anxiety can be helpful for autistic people if it is adapted to meet their needs, but there has been less research into such treatment for depression. We developed a treatment called guided self-help, which comprised materials for nine individual sessions and a manual to help the therapist guides work alongside autistic people. Two autistic people helped us to improve the session materials we had developed. The guides attended 2 days of training on how to deliver guided self-help. Seventy adults with a diagnosis of autism spectrum disorder and depression agreed to take part in the study. They were randomly allocated to guided self-help or to treatment as usual. Treatment as usual means whatever treatment would usually be available. We asked these adults to complete measures of depression, anxiety and other psychological symptoms, as well as their use of health and social care services, before treatment. We asked them to complete these measures again 10, 16 and 24 weeks later. We also invited them to take part in interviews about their experiences of the study. People who had guided self-help attended the treatment to the end and said that they found it acceptable and helpful. They suggested ways to improve the treatment materials. More people in the guided self-help group than in the treatment-as-usual group completed the 16- and 24-week follow-ups. Just over half of the people in the treatment-as-usual group did not attend the 16- and 24-week follow-ups. This would be a problem in a larger trial because we would not have enough information about the treatment-as-usual group to know if people in this group were doing better or worse than those in the guided self-help group. The findings of this study suggest that a larger trial to find out if guided self-help is effective in treating depression in autism would be helpful.

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