Primary chronic daily headache: Clinical and pharmacological aspects. A clinic-based study in Oman

This study on primary chronic daily headache was based on the 1996 proposed revision of the diagnostic criteria of the International Headache Society OHS). To investigate the relative frequency, clinical characteristics, and associated features of primary chronic daily headache in Omani patients, 17 1 patients visiting the Neurology Clinic at Sultan Qaboos University Hospit al were evaluated, Forty-five percent was diagnosed as suffering from prima ry chronic daily headache (female to male ratio, 1.7:1). Sixty-two percent suffered from transformed migraine and 34% from chronic tension-type headac he. The average age across sexes was 32.3 +/- 12.3 years. A dull heavy feel ing in the head was reported by 58% of patients and was associated in less than one third with associated features characteristic of migraine. All hea dache types shared the same trigger factors. All patients were taking medic ation, predominantly analgesics, at the time of their first visit. We concluded that primary chronic daily headache is very common with the re lative frequency of transformed migraine being similar to that found in Med iterranean studies. Also in Oman, chronic use/overuse of analgesics and non steroidal anti-inflammatory drugs is a problem that coexists with primary c hronic daily headache. Finally, the proposed revised IHS criteria are highl y recommended as a standard classification system for this type of headache .