As well as psychiatric disorders, many physical diseases and conditions can be comorbid with migraine.[Wang et al., 2010] Along with a number of other underlying factors, there is some evidence that some of the comorbidity of migraine may be mediated by a proinflammatory state.[Wang et al., 2010]
Determining the exact relationship between migraine and a given comorbidity is not straightforward; it is sometimes difficult to know which condition influences the risk of the other, or if there is a bidirectional relationship.[Wang et al., 2010] Moreover, two comorbid conditions may interact with each other, for example when restless legs syndrome reduces a person’s sleep.[Wang et al., 2010] Whatever the relationship, understanding the associations of migraine with its various comorbidities is important in order to provide good care to the patient.[Wang et al., 2010]
Reference:
Wang SJ, Chen PK, Fuh JL. Comorbidities of migraine. Front Neurol 2010; 1: 16.