Rate , Predictors and Outcome of Chronic Migraine

Nowadays, headache has been considered as one of the top global disabling medical conditions.1 Migraine is an important type of headache, and one of the chronic multifaceted neuro-inflammatory disorders.2 It is characterized by recurrent throbbing headache pain that typically affects one side of the head, and is often accompanied by nausea and disturbed vision. Migraine headache accounts for 1.4% of all neurological and mental disorders.2 It was reported that the estimated lifetime prevalence of migraine ranged 12%-18%.3 Chronic migraine is defined by the International Classification of Headache Disorders - ICHD-3 as having headaches for ≥ 15 days per month, for ≥ 3 months , which ≥ 8 days/month are linked to migraine. Chronic migraine affects around 1%-4% of the population and chronic tension-type headache about 2.2%.4 Approximately 25%-50% of those affected also have medication overuse headache, which has a population prevalence of 1%.5 Chronic headache is a severely disabling long-term condition, with higher symptom ,frequency and severity than episodic headache.6 Diagnostic criteria of chronic migraine according to ICHD(7) Description: Headache occurring on 15 or more days/month for more than 3 months, which, on at least 8 days/month, has the features of migraine headache. Diagnostic criteria: A. Headache (migraine-like or tension-type-like1) on ≥15 days/month for \>3 months, and fulfilling criteria B and C B. Occurring in a patient who has had at least five attacks fulfilling criteria B-D for 1.1 Migraine without aura and/or criteria B and C for 1.2 Migraine with aura C. On ≥8 days/month for \>3 months, fulfilling any of the following: 1. criteria C and D for 1.1 Migraine without aura 2. criteria B and C for 1.2 Migraine with aura 3. elieved by the patient to be migraine at onset and relieved by a triptan or ergot derivative D Not better accounted for by another ICHD-3 diagnosis. Episodic migraine (EM) is characterized by those with migraine who have 0 to 14 headache days per month, while chronic migraine (CM) is characterized by 15 or more headache days per month. The relationship between EM and CM is complex. EM progresses to CM at the rate of 2.5% per year \[8\], and CM often remits to EM (2-year transition rate of 26%) \[9\]. Several factors have been associated with migraine chronification (predictors) ; such as age: * Age \*Sex \*Presence of depression \*Presence of anxiety * sleep disorder \*obesity \*medication compliance \*medication overuse * coffee \* low income \*allodynia \*other pain disordes comorbidities. Our aims were to identify factors that predict prognosis in patients with chronic Migraine.