Potential treatment mechanisms in a mindfulness-based intervention for people with progressive multiple sclerosis

Objectives

To explore putative mediators of a mindfulness-based intervention to decrease distress in people with multiple sclerosis (MS) and to explore the patients’ perspectives on this intervention.

Design

We used an explanatory mixed methods design incorporating quantitative data from a pilot randomized control trial and a qualitative interview study with people who completed the mindfulness intervention.

Methods

People with MS (n = 40) completed standardized measures of distress (outcome), and acceptance, decentring, self-compassion, and self-efficacy (potential mediators). Semi-structured interviews (n = 15) of patients’ experiences of the mindfulness intervention were analysed deductively and inductively.

Results

Decentring post-intervention explained 13% of the 3-month change in distress and between 27% and 31% of concurrent changes in distress. Acceptance changed only slightly, and as a result, the indirect effect accounts for only 2% of future distress and between 3% and 11% of concurrent distress. Qualitative data showed that acceptance and self-compassion needed more time to develop, whereas decentring could be implemented readily after being introduced in the sessions. Self-efficacy also had a large mediating effect. Participants in their interviews talked about group dynamics and prior expectations as essential elements that determine their engagement with the course and their level of satisfaction.