A comparison of disability and psychological factors in migraine and transformed migraine.

The classification of patients with migraine who develop chronic daily headache is controversial, with some classifying such patients as 'transformed migraine'. We compared patients with intermittent migraine attacks and patients with transformed migraine in terms of mean headache intensity on days with headache, depression, pain-related anxiety and headache-related disability. Patients classified clinically as also having tension-type headache were excluded. Aside from the number of days with headache per month, patients with intermittent migraine attacks and patients with transformed migraine were very similar in terms of all parameters studied. Our results support the concept that these two headache groups are closely related.