Identifying mindfulness and acceptance as mediators between negative affect, functional disability and emotional distress in patients with fibromyalgia.

Fibromyalgia (FM) is a prevalent disabling condition characterised by chronic widespread pain. It is considered a complex illness in which the prognosis is conditioned by affective and cognitive mediators still largely unknown in FM. To investigate the correlation between psychological variables (acceptance, negative affect, and mindfulness) and functional disability or physical impact, anxiety/depression symptoms and emotional distress, and also to evaluate the mediating role of acceptance and mindfulness between negative affect, physical impact, anxiety/depression and emotional distress in individuals with FM. Two hundred and fifty-one patients with FM who met the 2010 ACR criteria were included and filled out validated self-reported screening measures. The study explored Pearson's correlation coefficients and multiple mediation using a Preacher and Hayes's computational software tool, including the indirect effect associated with the two mediators (mindfulness and acceptance). Functional disability or physical impact, anxiety/depression symptoms and emotional distress correlated positively with negative affect (r= 0.580) and negatively with acceptance and mindfulness (r= -0.579 and r= -0.471; all p-values <0.001), respectively. The mediation analyses showed that acceptance and mindfulness mediated the relationship between negative affect and dependent variables such as physical impact, anxiety/depression symptoms and distress. The findings highlight that mindfulness and acceptance have a significant indirect effect on physical impact, anxiety/depression and emotional distress when controlling for negative affect as an independent variable in the FM patients. Future investigation should replicate and extend these outcomes in other study populations to determine the mediating role of mindfulness and acceptance in FM.