Alexithymia and psychological distress in fibromyalgia and chronic migraine. A cross-sectional study

Objective: Several studies have shown a strong association between alexithymia and psychological distress in both healthy and clinical populations. The aim of this study was to investigate the prevalence and association between alexithymia and psychological distress in individuals with fibromyalgia (FM) and chronic migraine (CM) compared with healthy controls (HC).Methods: A cross-sectional study was conducted. Two hundred fifty women with FM (age: 51.2 +/- 10.5) and 250 women with CM (age: 46.1 +/- 11.5) were assessed with the Toronto Alexithymia Scale (TAS-20) and the Hospital Anxiety and Depression Scale (HADS) and compared with HCs (n = 280; age: 51.8 +/- 9.0) by one-way analyses of variance. A moderation analysis was performed to examine the moderation effect of groups on the relationship between alexithymia and psychological distress.Results: Differences between groups showed significantly higher scores for TAS-20 [F(2,755) = 11.7, p < .001] and HADS [F(2,763) = 31.7, p < .001] in FM, compared with CM and HCs. The moderation analysis showed that both clinical groups and TAS-20 (beta = 0.20, p < .001) were significant predictors, as well as the interaction terms. The slope of the correlation curve was more pronounced in the patient groups, indicating that the degree of alexithymia had a significantly higher influence on the HADS total score in the patient groups.Conclusion: The results suggest a common psychological dysregulation in FM and CM, with a slight but greater prevalence of alexithymia and psychological distress in FM. These data suggest that although there is a similar psychological substrate, it is expressed in a different expression of somatic symptoms.