Acceptance and commitment therapy for older people with treatment-resistant generalised anxiety disorder: the FACTOID feasibility study.

Abstract

Generalised anxiety disorder, characterised by excessive anxiety and worry, is the most common anxiety disorder among older people. It is a condition that may persist for decades and is associated with numerous negative outcomes. Front-line treatments include pharmacological and psychological therapy, but many older people do not find these treatments effective. Guidance on managing treatment-resistant generalised anxiety disorder in older people is lacking. To assess whether or not a study to examine the clinical effectiveness and cost-effectiveness of acceptance and commitment therapy for older people with treatment-resistant generalised anxiety disorder is feasible, we developed an intervention based on acceptance and commitment therapy for this population, assessed its acceptability and feasibility in an uncontrolled feasibility study and clarified key study design parameters. Phase 1 involved qualitative interviews to develop and optimise an intervention as well as a survey of service users and clinicians to clarify usual care. Phase 2 involved an uncontrolled feasibility study and qualitative interviews to refine the intervention. Participants were recruited from general practices, Improving Access to Psychological Therapies services, Community Mental Health Teams and the community. Participants were people aged ≥ 65 years with treatment-resistant generalised anxiety disorder. Participants received up to 16 one-to-one sessions of acceptance and commitment therapy, adapted for older people with treatment-resistant generalised anxiety disorder, in addition to usual care. Sessions were delivered by therapists based in primary and secondary care services, either in the clinic or at participants' homes. Sessions were weekly for the first 14 sessions and fortnightly thereafter. The co-primary outcome measures for phase 2 were acceptability (session attendance and satisfaction with therapy) and feasibility (recruitment and retention). Secondary outcome measures included additional measures of acceptability and feasibility and self-reported measures of anxiety, worry, depression and psychological flexibility. Self-reported outcomes were assessed at 0 weeks (baseline) and 20 weeks (follow-up). Health economic outcomes included intervention and resource use costs and health-related quality of life. Fifteen older people with treatment-resistant generalised anxiety disorder participated in phase 1 and 37 participated in phase 2. A high level of feasibility was demonstrated by a recruitment rate of 93% and a retention rate of 81%. A high level of acceptability was found with respect to session attendance (70% of participants attended ≥ 10 sessions) and satisfaction with therapy was adequate (60% of participants scored ≥ 21 out of 30 points on the Satisfaction with Therapy subscale of the Satisfaction with Therapy and Therapist Scale-Revised, although 80% of participants had not finished receiving therapy at the time of rating). Secondary outcome measures and qualitative data further supported the feasibility and acceptability of the intervention. Health economic data supported the feasibility of examining cost-effectiveness in a future randomised controlled trial. Although the study was not powered to examine clinical effectiveness, there was indicative evidence of improvements in scores for anxiety, depression and psychological flexibility. Non-specific therapeutic factors were not controlled for, and recruitment in phase 2 was limited to London. There was evidence of high levels of feasibility and acceptability and indicative evidence of improvements in symptoms of anxiety, depression and psychological flexibility. The results of this study suggest that a larger-scale randomised controlled trial would be feasible to conduct and is warranted. Current Controlled Trials ISRCTN12268776. 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. 25, No. 54. See the NIHR Journals Library website for further project information.