Page 43 - The clinical aspects and management of chronic migraine Judith Anne Pijpers

However, our study does suggest an even stronger comorbidity between migraine and symptoms of anxiety, than between migraine and symptoms of depression per se. This is particularly interesting, since most studies hitherto focused on the comorbidity between migraine and depression, whilst the comorbidity of migraine and anxiety is a largely unexplored area. Larger and prospective studies on the comorbidity of migraine and anxiety disorders are necessary to establish the exact magnitude of this comorbidity. Our study shows that anxiety arousal might be the corresponding component, but the underlying mechanism should be further investigated.
Because the co-occurrence between migraine and affective disorders is not fully explained by mechanisms such as somatic depression or overlapping symptomatology we argue that there is a true comorbidity between migraine and depression. Additionally, previous studies showed a bidirectional relationship, in which the risk for depression is five times increased in migraine patients, and vice versa, the risk for migraine is three times increased in patients with depressio.2;3 This bidirectional association suggests shared underlying mechanisms, presumably shared genetic factors.4;5 However, further genetic research did not yet result in clues which exact genes are involved in this association. The current study stresses the importance of a dimensional approach for depression in migraine in a research setting, as the current concept of depression probably is too heterogeneous for detecting genetic variants involved in this association. Using subgroups of migraine patients, based on the tripartite model of depression and anxiety, may be warranted in further genetic research on the comorbidity of migraine and affective disorders.
Comorbid depression in migraine is an important predictor of substance dependence and is common in chronic migraine patients, in particular in those with overuse of acute headache medication.31 Thus a triad between migraine chronification, depression and medication overuse has been suggested.32-34 In this triad, cutaneous allodynia plays a role. Allodynia, the perception of pain in response to non-noxious stimuli to the normal skin, is a common feature accompanying migraine attacks. Previously, we showed that depression and high migraine attack frequency (as a marker of chronification) are independently associated with cutaneous allodynia.23 The present study supports this finding and shows that both cutaneous allodynia and high migraine frequency, are
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Affective disorders in migraine patients
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