Emotional Dynamics in Fibromyalgia: Pain, Fatigue, and Stress Moderate Momentary Associations Between Positive and Negative Emotions.

Affective disruptions, particularly deficits in positive affect, are characteristic of fibromyalgia (FM). The Dynamic Model of Affect provides some explanations of affective disruptions in FM, suggesting that the inverse association between positive and negative emotions is stronger when individuals with FM are under greater stress than usual. However, our understanding of the types of stressors and negative emotions that contribute to these affective dynamics is limited. Using ecological momentary assessment (EMA) methods, 50 adults who met the FM survey diagnostic criteria rated their momentary pain, stress, fatigue, negative emotions (depression, anger, and anxiety), and positive emotions 5X/day for eight days using a smartphone application. Results of multilevel modeling indicate that, consistent with the Dynamic Model of Affect, there was a stronger inverse association between positive emotion and negative emotions during times of greater pain, stress, and fatigue. Importantly, this pattern was specific to depression and anger, and was not present for anxiety. These findings suggest that fluctuations in fatigue and stress may be just as important or more important than fluctuations in pain when understanding the emotional dynamics in FM. In addition, having a more nuanced understanding of the role that different negative emotions play may be similarly important to understanding emotional dynamics in FM. PERSPECTIVE: This article presents new findings on the emotional dynamics in FM during times of increased pain, fatigue, and stress. Findings highlight the need for clinicians to conduct a comprehensive evaluation of fatigue, stress, and anger in addition to more routinely assessed depression and pain when working with individuals with FM.