An updated review of migraine and co-morbid psychiatric disorders.

General population studies suggest a non-casual association (co-morbidity) between migraine, major depression and anxiety disorders (panic attack disorder, obsessive-compulsive disorder, generalised anxiety disorder). The risk of developing affective and anxiety disorders has not increased uniformly in the different migraine subtypes, but it is more elevated in migraine with aura patients. The relationship between migraine and depression is "bi-directional" (i. e., migraineurs have a more than three-fold risk of developing depression compared with non-migraine patients, while depression patients that have never suffered from migraine before have a more than three-fold risk of developing migraine compared with non-depressed patients) and specific (i. e., the presence of migraine or severe non-migraine headache increases a patient's risk of developing depression or panic attack disorder, whereas the presence of depression or panic attack disorder is associated with a greater risk of developing migraine, but not severe non-migraine headache). The association described in this review has significant pathogenetic, clinical and therapeutical implications.