Mediators of Change in Cognitive-Behavioral Couple Therapy for Genito-Pelvic Pain: Results of a Randomized Clinical Trial

Objective: A novel cognitive-behavioral couple therapy (CBCT) has shown efficacy for treating provoked vestibulodynia (PVD), the most common type of genito-pelvic pain, in comparison to topical lidocaine. However, mechanisms of therapeutic change have not been determined. We examined women's and partners' pain self-efficacy and pain catastrophizing as mediators of change in CBCT, using topical lidocaine as a control group. Method: 108 couples coping with PVD were randomized to 12-week CBCT or topical lidocaine and assessed at pre-treatment, post-treatment, and six-month follow-up. Dyadic mediation analyses were conducted. Results: CBCT was not more effective in increasing pain self-efficacy than topical lidocaine, so this mediator was discarded. In women, decreases in pain catastrophizing at post-treatment mediated improvement in pain intensity, sexual distress, and sexual function. In partners, decreases in pain catastrophizing at post-treatment mediated improvement in sexual function. Partners' decreases in pain catastrophizing also mediated reductions in women's sexual distress. Conclusions: Pain catastrophizing may be a mediator specific to CBCT for PVD, explaining improvements in pain and sexuality.