630 (39%) of 1600 patients seen in a Headache Clinic over a three year period had chronic daily headaches (CDH). In 78% of these CDH patients, the daily headaches evolved out of a prior history of episodic migraine; these patients we designate as having “transformed” or “evolutive” migraine. The other 12% had migraine headaches which were daily from the start.

Patients with transformed migraine, in contrast to those with daily headaches from the start, have a significantly higher incidence of positive family history of migraine, menstrual aggravation of migraine, identifiable trigger factors, associated G.I. and neurological symptoms, and early morning awakening with headache.

The CDH group in general over-used symptomatic medication and exhibited abnormalities on behavioral scale testing. Withdrawal of daily symptomatic medication, institution of a low tyramine low caffeine diet, initiation of prophylactic anti-migraine therapy, and biofeedback and behavioral therapy, gave worthwhile improvement in 76% of chronic daily headache patients.

Factors which promote “evolution” of migraine from intermittent to chronic daily occurrence are not well-defined but may include medication abuse, medication withdrawal, and psychiatric disturbances.