Pain Catastrophizing Mediates the Association Between Mindfulness and Psychological Distress in Chronic Pain Syndrome.

AIM: Trait mindfulness has been found to be inversely associated with emotional distress such as depression and anxiety among patients suffering from pain. The current study investigated the putative mechanisms underlying these associations by examining whether pain catastrophizing mediates the association between mindfulness and psychological distress and whether this model differs in patients suffering from chronic pain compared to patients experiencing nonchronic pain in a medical rehabilitation setting. METHODS: Forty-eight patients in their subacute stage of recovery participated in the study. Seventeen participants had a diagnosis of chronic pain. Trait mindfulness was assessed using the Mindful Attention Awareness Scale, pain catastrophizing was assessed using the Pain Catastrophizing Scale, depression symptoms were assessed using the Patient Health Questionnaire, and anxiety was assessed using the Generalized Anxiety Disorder scale. Two mediation models were used, with pain catastrophizing mediating the association between mindfulness and depression and anxiety. RESULTS: Catastrophizing significantly mediated the association between trait mindfulness and depression (P < 0.05, confidence interval [CI] = -0.35, -0.05). Catastrophizing also mediated the relationship between trait mindfulness and anxiety (P < 0.05, CI = -0.34, -0.04). Two moderated mediation models were tested, in which pain catastrophizing fully mediated the relationship between trait mindfulness and depression and anxiety, but only in patients with chronic pain. CONCLUSIONS: The negative association between trait mindfulness and psychological distress may thus be partly attributed to pain catastrophizing: individuals high in trait mindfulness engage in less catastrophic thinking and therefore experience less distress. Importantly, this was only observed in the patients with chronic pain. These results further underscore the need to cope with pain catastrophizing and encourage mindfulness among patients with chronic pain.

The associations between executive functions and different aspects of perceived pain, beyond the influence of depression, in rehabilitation setting.

We investigated the relations between several aspects of Perceived Pain (PP) and different measurements of Executive Functions (EFs), above the influence of depression, in the context of medical rehabilitation. Eighty-one neurologically intact patients participated in this study in their sub-acute stage of recovery. Different aspects of EFs were assessed using the Wisconsin Card Sorting Test (WCST), the Stop-Signal Test (SST) and the Digit Span Backward subtest of the WAIS-III (Span-B). Different aspects of PP were measured: Pain Disability Index (PDI), The Short-Form McGill Questionnaire (SF-MPQ) and the Pain Catastrophizing Scale (PCS). Depression symptoms were assessed using the Patient Health Questionnaire. The results indicate that irrespective of the presence of depression, mental flexibility is correlated with pain disability and pain severity (WSCT - PDI partial correlation: r = -.23; p=.047, WSCT - SF-MPQ partial correlation: r = -.31; p = .006). Response inhibition is correlated with pain disability (SST - PDI partial correlation: r = .37; p = .001). Updating was not correlated with any of the PP aspects. These results remain much the same after removing the chronic pain patients from the analyses. The present study emphasizes the multidimensional nature of the term "perceived pain", as well as the term "executive functions", and the relations between them.