Alexithymia as a moderator of affective modulation of symptom reporting in functional somatic syndromes

Abstract

Functional somatic syndromes (FSS), such as Chronic Fatigue Syndrome (CFS) and fibromyalgia, are characterized by chronic and debilitating somatic symptoms that are insufficiently explained by structural organic dysfunction. It has been suggested that alexithymia might contribute to the experience of symptoms in FSS because the inability to correctly identify, classify, and interpret emotions is related to an increased confusion between changes in bodily states accompanying negative emotions and changes in bodily states that are a sign of disease. To investigate this, patients with fibromyalgia and/or chronic fatigue syndrome (CFS: N = 81) and healthy controls (HC: N = 41) viewed series of neutral, positive, and negative affective pictures. After every picture series, participants filled out a somatic symptom checklist. Alexithymia was measured with the "difficulty identifying feelings" (DIF) subscale of the Toronto Alexithymia Scale. We found that negative affective states elicited elevated symptom reports in patients experiencing fibromyalgia and/or CFS, but not in healthy individuals. Interestingly, this difference between patients and controls disappeared when controlling for DIF as a full mediator of this effect, indicating that the exaggerated affective modulation of symptom reporting in FSS patients can be explained by higher average levels of alexithymia in FSS patients.