Exploring the contextual role of pain severity as a moderator of the relationship between activity patterns and the physical and mental functioning of women with fibromyalgia.

INTRODUCTION: In past years, and mostly due to contextual psychological therapies, it has been argued that particular behavioural patterns may be useful in certain contexts, but not in others. The goal of this study has been to explore whether pain severity is indeed a contextual factor influencing the relationship between two controversial activity patterns, namely pacing and persistence, and functionality in people with fibromyalgia. METHODS: Participants were 231 women diagnosed with fibromyalgia. A multivariate regression was conducted to explore the moderating role of pain severity in the relationship between activity patterns and outcomes (i.e. fibromyalgia impact and depressive symptoms). RESULTS: Excessive persistence (interaction: t = -2.45, p = 0.015) and pain-contingent persistence (interaction: t= -2.13, p = 0.034) were more strongly associated with fibromyalgia impact when people experienced less severe pain. Pacing for pain reduction was only significantly related to depressive symptoms at very severe (M = 10) pain levels (interaction: ß= -0.18, t= -2.73). CONCLUSIONS: The results here reported suggest that the context in which behaviour occurs is relevant when the utility of certain behaviour patterns is considered. The clinical implications of this are clear, as it would justify adapting the recommendations given to patients according to their pain severity status. SIGNIFICANCE: This manuscript shows that some activity patterns (i.e. pacing to conserve energy for valued activities) might be advisable regardless of pain levels. Conversely, some patterns might be especially recommended (i.e. pain-reduction pacing) or inadvisable (i.e. excessive and pain-contingent persistence) depending on pain levels (i.e. severe and mild pain, respectively).