Literature shows high rates of comorbidity between fibromyalgia (FM) and mood disorders, especially major depressive disorder (MMD), reported in more than half of the cases. Consistently, patients with FM also present high rates of mood spectrum symptoms, despite scant data are still available on the relationship with antidepressant treatment outcomes. The present study was aimed at exploring the clinical outcome of patients with FM-MDD comorbidity naturalistically treated with antidepressant drugs, besides the relationships between mood spectrum symptoms and the treatment response.
A total sample of 40 patients with FM and MDD, who started a treatment with an antidepressant drug, was recruited at the Rheumatology Unit of the University of Pisa, Italy. Patients were evaluated at baseline and after 1 (T1) and 6 months (T2) of the treatment with an antidepressant drug. Assessments included: the Mood Spectrum-Self Report (MOODS-SR) for mood spectrum symptoms, the Short Form Health Survey (SF-36) for the global functioning and the Clinical Global Impression (CGI) for the clinical severity and improvement. All instruments were administered at baseline and the SF-36 and CGI were repeated at T1 and T2.
Twenty-eight (70%) patients reported an improvement at the CGI at T2. At T1 and T2 the CGI item-1 and most of the SF-36 domain scores significantly improved with respect to the T0, with the exception of the "role physical" and "role emotional" subscales. Improved patients reported higher scores in the energy depressive MOODS-SR domain. Furthermore, correlations emerged between several MOODS-SR domains and the CGI or SF-36 subscales scores at T0.
Our results corroborate previous findings on the role of antidepressant drugs in the management not only of MDD symptoms, but also of the painful component of FM. FM patients should be investigated for Mood Spectrum symptomatology considering its prominent role on the manifestations of the disorder and treatment outcome.