Tinnitus – an acceptance-based approach

Abstract: Tinnitus is a highly prevalent health condition creating moderate or severe interference on mood, sleep and daily functioning for a group of those affected. The aims of this thesis were 1) to explore the role of acceptance and psychological flexibility in understanding tinnitus interference both experimentally and with a longitudinal design 2) to evaluate the immediate and long-term outcomes of an acceptance based behaviour therapy (Acceptance and Commitment Therapy; ACT) in the treatment of people with tinnitus and, 3) to investigate the relationship between treatment outcome and processes assumed to be the active ingredients of treatment (acceptance and cognitive defusion).Study I (n=47) was an experiment comparing the impact of acceptance to that of thought suppression or a neutral instruction on the ability to maintain attention on an imagery task. Results indicated that participants could benefit from an acceptance strategy when performing the task. Study II (n=47) was a longitudinal trial studying the mediating role of acceptance on the relationship between tinnitus interference at baseline and tinnitus interference, anxiety, life quality, and depression at a seven-month follow-up. Full mediation was found for life quality and depression, and partial mediation for tinnitus interference. Study IV (n=64) was a randomised controlled trial evaluating the immediate and long-term effects of ACT in comparison to those of Tinnitus Retraining Therapy (TRT) and to a wait list control. Results showed that ACT had large immediate effects on tinnitus interference in comparison to wait list, and medium long-term effects in comparison to TRT. Results were also seen on secondary outcome. Self-reported tinnitus acceptance significantly mediated the immediate outcome of ACT. Study III (n=24) was a process study where the video recorded sessions of ACT from study IV were observed and rated with regard to client behaviour. Results showed that in-session acceptance and defusion behaviours rated early in therapy were predictors of sustained positive treatment effects of ACT. These associations continued to be substantial even when controlling for the prior improvement in outcome. This whereas prior symptom change could not predict process variables rated late in therapy. Participants in all trials were chronic tinnitus patients, mainly from different departments of audiology. These findings implicate that 1) acceptance and psychological flexibility may contribute to the understanding of tinnitus interference 2) ACT can reduce tinnitus interference in a group of normal hearing tinnitus patients and 3) acceptance and cognitive defusion are important processes in ACT, related to outcome.