Associations between psychological flexibility and daily functioning in endometriosis-related pain.

Objectives: Processes of psychological flexibility (PF) are positively associated with health and wellbeing in several chronic pain disorders. However, these processes have not been investigated in endometriosis, a chronic pain disorder affecting 5-10 % of women worldwide. This study is a preliminary investigation of the associations between PF or psychological inflexibility (PI) and daily functioning in people with a primary diagnosis of endometriosis.

Methods: This study is based on a secondary analysis of survey data from Swedish-speaking adult participants with chronic pain recruited online. The current study included only those reporting a diagnosis of endometriosis and significant long-term pain. All participants completed the Multidimensional Psychological Flexibility Inventory (MPFI), a measure of PF and PI, as well as other measures of PF, and measures of pain and daily functioning. Correlation and multiple regression analyses were performed to examine relations of PF and PI with measures of pain and daily functioning.

Results: In general, PF facet scores from the MPFI did not correlate with pain interference but did correlate with depression, with the exception of acceptance. The overall facets of PI appeared to perform better as correlates and in regression. Established measures of PF performed in correlation and regression analyses generally as has been observed in other chronic pain populations, with significant positive associations.

Conclusions: In this preliminary analysis of PF and PI in participants with endometriosis-related pain, these processes appear relevant, especially in understanding depression, but results varied along with the measures used. Specifically, when employing the MPFI, the PI facets emerged as stronger correlates. The findings underscore the potential benefit of incorporating assessments of PF and PI as process variables in endometriosis-research, but also that careful consideration should be given when selecting instruments.