[Clinical features of daily chronic headache]

Although the International Headache Society considers chronic tension headache to be a chronic headache, patients with daily chronic headache may have pain which is not only due to tension but also has migrainous features.

To evaluate the clinical differences and abuse of drugs in a group of patients with chronic daily headache who were consecutively evaluated in the Neurology Clinic.

We consider the patients to have daily chronic headache when they have had pain at least 6 days a week for the past 6 months. Using this criterion, we studied 112 patients, of whom 90 (80.4%) were women and 22 (19.6%) men. Results. Sixty nine (61.6%) had transformed migraine and 43 (38.4%) tension headache. There were no differences in their current ages but the age of onset of the headaches varied (p = 0.000,t). Unilateral pain, trigger factors and a family history were more frequent in the cases of transformed migraine. Eighty four patients (75%) abused analgesics. Although we found different pain intensities (p = 0.000, chi 2) there was no difference in the weekly consumption of analgesics (p = 0.64, t) in the mg/week of ergotamine (p = 0.96, t) nor in absence from work between the two types of headache.

In spite of clinical differences between transformed migraine and tension headache, which may help diagnosis, in our series abuse of analgesics (including ergotamine) was a common characteristic.