Clinical Study attributes
The term "refractory" migraine describes a particularly aggressive form of the disease in which the patient does not benefit from any of the preventive therapies with the various classes of drugs available, including treatment with monoclonal antibodies directed against Calcitonin Gene Related Peptide (CGRP). Anxiety, depressive symptoms, somatization, and pain hypersensitivity are significantly more prevalent in refractory migraineurs than in non-refractory subjects who benefit from preventive therapies, suggesting that these symptoms may contribute to treatment refractoriness. Recently, in a preliminary study on the efficacy of a CGRP-targeting monoclonal antibody in Chronic Migraine (CM) patients with at least 3 failures to previous preventive treatments, the investigators showed a higher prevalence of psychological disturbances in those who did respond to the monoclonal antibody compared with the responders. These data, although preliminary, point to a more psychologically complicated picture in non-responder patients compared with responders. To date, however, no neurobiological evaluations are available to explain how psychological comorbidities may contribute to treatment refractoriness. Isolated clinical evidence and growing pre-clinical evidence suggests a role for the endocannabinoid system in migraine. Hence, the present study aims to identify psychological and biological factors associated with refractory migraine. The investigators' hypothesis is that patients presenting with psychological disorders may bear an associated dysfunction of the endocannabinoid system, which makes them more resistant to migraine preventive therapies, including monoclonal antibodies directed against CGRP.