Approach as a key for success: Reduced avoidance behaviour mediates the effect of exposure therapy for fibromyalgia

• Published in: Behaviour research and therapy 2019-11, Vol.122, p.103478-103478, Article 103478
• Main Authors: Hedman-Lagerlöf, Maria, Andersson, Erik, Hedman-Lagerlöf, Erik, Wicksell, Rikard K., Flink, Ida, Ljótsson, Brjánn
• Format: Article
• Language: English
• Subjects: Approach-Avoidance; Avoidance behavior; Avoidance behaviour; Behavior change; Behavior modification; Chronic pain; Cognitive behaviour therapy; Exposure therapy; Exposure-based therapy; Fibromyalgia; Mediation analysis; Medicin och hälsovetenskap; Pain; Reactivity; Severity; Suffering; Vigilance; Worry
• ISSN: 0005-7967; 1873-622X; 1873-622X
• DOI: 10.1016/j.brat.2019.103478

Fibromyalgia (FM) is a prevalent chronic pain disorder associated with large suffering and substantial societal costs. Pain-related avoidance behaviour and hypervigilance to bodily symptoms are common in FM and contribute in maintaining and exacerbating the disorder. Exposure therapy targeting avoidance behaviours and hypervigilance has shown promise in the treatment of FM. The present study investigated mediators of treatment outcome in exposure therapy for FM. We used data from a randomised trial, where 140 participants were allocated to 10-week internet-delivered exposure therapy or to a waiting-list control condition. The main outcome variable (FM symptoms) and the hypothesized mediators (FM-related avoidance behaviour, mindful non-reactivity and FM-related worry) were measured weekly throughout treatment. Mediation analyses were conducted using linear mixed effects models with bootstrap replication and time-lagged analysis. Results indicated that all three process variables were significant mediators of FM severity. However, in the time-lagged analyses, only FM-related avoidance behaviour displayed a unidirectional relationship over time with FM symptoms, suggesting a causal effect. Thus, results illustrate that changes in avoidance behaviour mediate the outcome of exposure on FM symptoms, which implies that avoidance behaviour is an important treatment target in exposure therapy. •Avoidance behaviour is a potential maintaining factor in fibromyalgia (FM).•We investigated avoidance and other processes as mediators in FM exposure therapy.•Avoidance behaviour, mindful non-reactivity and worry were significant mediators.•However, only avoidance behaviour had a unidirectional relationship with outcome.•Targeting avoidance behaviour may be important in exposure therapy for FM.