Intervening variables in group-based acceptance & commitment therapy for severe health anxiety. (May 2017)

• Record Type: Journal Article
• Authors: Eilenberg, Trine; Hoffmann, Ditte; Jensen, Jens S.; Frostholm, Lisbeth
• Is Part Of: Behaviour research and therapy. Volume 92(2017)
• Page Start: 24
• Page End: 31
• Publication Date: 2017-05
• Subjects: Hypochondriasis -- Illness anxiety disorder -- Health anxiety -- Acceptance and Commitment Therapy -- Mediation -- Intervening variables -- Mindfulness; ACT Acceptance and Commitment Therapy -- ACT-G Acceptance and Commitment Group Therapy -- CBT Cognitive Behavioral Therapy -- FFMQ Five Facet Mindfulness Questionnaire -- HA Health Anxiety -- MBCT Mindfulness-based Cognitive Therapy -- PF Psychological flexibility -- POC Product of coefficients approach -- SEM Structural Equation Modeling -- SRM Standardized response mean; Cognitive therapy -- Periodicals; Psychotherapy -- Periodicals; 616.891
• DOI: 10.1016/j.brat.2017.01.009
• Languages: English
• ISSNs: 0005-7967

Abstract

Abstract: Objective: The present study is based on a previously reported successful randomized controlled trial (RCT) on Acceptance and Commitment Group therapy (ACT-G) for severe health anxiety (HA) and investigates intervening variables of ACT for HA. The process primarily targeted by ACT is psychological flexibility (PF). No randomized study has yet examined the possible intervening variables of ACT for HA. Methods: 126 patients diagnosed with severe HA were enrolled in the RCT of which 107 were included in the analyses. The outcome measure was illness worry (Whiteley Index) and included process variables were PF and facets of mindfulness. Results: Statistically significant indirect effects (IE) of ACT-G on the outcome of illness worry 6 months after treatment were found for PF (IE = −5.5, BCa 99% CI -12.3;-1.2) and one mindfulness subscale, namely 'non-react' (IE = −6.5 BCa 99% CI -15.3: 1.0). Conclusion: In line with the ACT model of change, PF may have a small to moderate IE on decrease in illness worry. Of the mindfulness scales, only 'non-react' showed a significant IE. Although tentative, due to no active comparison control condition, these results support that PF is a intervening variable in ACT treatment aimed at reducing illness worry in patients with severe HA. Highlights: Data are scarce on mechanisms of change in health anxiety (HA) treatment. The results support the Acceptance and Commitment Therapy (ACT) model of change. Psychological flexibility had a small to moderate indirect effect (IE) on illness worry. Only the mindfulness subscale 'non-react' also showed a significant IE. Further research on mechanisms of change is needed to enhance HA treatment efficacy.