Psychological Flexibility Is Key for Reducing the Severity and Impact of Fibromyalgia.

Fibromyalgia has a significant impact on the lives of patients; symptoms are influenced by psychological factors, such as psychological flexibility and catastrophizing. The objective of this study was to determine the importance of these variables in moderating the association between the severity and impact of fibromyalgia symptoms. A total of 187 patients from a general hospital population were evaluated using the Combined Index of Severity of Fibromyalgia (ICAF), the Fibromyalgia Impact Questionnaire (FIQ), the Acceptance and Action Questionnaire-II (AAQ-II), and the Pain Catastrophizing Scale (PCS). A series of multiple regression analyses were carried out using the PROCESS macro and decision tree analysis. The results show that psychological flexibility modulates the relation between severity and the impact of fibromyalgia symptoms. Catastrophism has residual importance and depends on the interaction with psychological flexibility. Interaction occurs if the severity of the disease is in transition from a mild to a moderate level and accounts for 40.1% of the variance in the sample. These aspects should be considered for evaluation and early intervention in fibromyalgia patients.