title: Similarities and differences between chronic migraine and episodic migraine.
abstract: OBJECTIVE
  To quantify and characterize the similarities and the differences between chronic migraine (CM) patients with medication overuse and episodic migraine (EM) patients with only occasional analgesic use.
  
  
  BACKGROUND
  Population-level epidemiology, characteristics, mechanisms of chronic daily headache, and medication-overuse headache have been widely studied but patient characteristics have received less attention. Methods.-We compared sociodemographic data, family history, physiological and medical history, health services utilized, drugs taken/prescribed, and outcome of 2 groups of subjects: 150 patients, suffering from CM, complicated by probable medication-overuse headache (CM group), consecutively admitted during 2005 to the inpatients' ward of the Headache Centre of the University Hospital of Modena and Reggio Emilia, Italy, to undergo withdrawal from their overused medications; 100 patients suffering from EM, uncomplicated by medication overuse (EM group), consecutively referred to the outpatients' ward of the Headache Centre during November and December 2005.
  
  
  RESULTS
  All sociodemographic characteristics were significantly different between the 2 groups. As a whole, the CM group began to suffer from migraine earlier than the EM group. Drug and/or alcohol abuse was significantly higher among first-degree relatives of CM (19%) than of EM (6%) patients. The most frequent comorbid disorders were psychiatric (67%) and gastrointestinal diseases (43%) in the CM group, and allergies in the EM group (31%). Seventy percent of CM patients and 42% of EM patients were taking daily at least another drug, besides those for headache treatment. Most overused medications in the CM group were triptans (43%); the EM group used above all single NSAIDs (56%). At 3-month follow-up, prophylactic treatments reduced, by at least 50%, the frequency of headache in about three-fourths of patients of both the groups; however, headache remained significantly more frequent in the CM than in EM group: only a minority (15%) of CM patients reverted to a headache frequency comparable to that of the EM group.
  
  
  CONCLUSIONS
  CM patients present more multiple comorbid disorders, polypharmacy, and social impediments than EM patients. These associated conditions complicate CM clinical management. Even after withdrawal from medication overuse, CM could not be completely reverted by current prophylactic treatments.
authors.affiliation: Division of Toxicology and Clinical Pharmacology, Headache Centre, University Centre for Adaptive Disorders and Headache, Section Modena II, University of Modena and Reggio Emilia, Modena, Italy.
authors.forename: Anna
authors.initials: A
authors.lastname: Ferrari
authors.forename: Sheila
authors.initials: S
authors.lastname: Leone
authors.forename: Anna Valeria
authors.initials: AV
authors.lastname: Vergoni
authors.forename: Alfio
authors.initials: A
authors.lastname: Bertolini
authors.forename: Grazia
authors.initials: G
authors.lastname: Sances
authors.forename: Ciro Pio Rosario
authors.initials: CP
authors.lastname: Coccia
authors.forename: Alessandra
authors.initials: A
authors.lastname: Ottani
authors.forename: Diego
authors.initials: D
authors.lastname: Pinetti
authors.forename: Emilio
authors.initials: E
authors.lastname: Sternieri
mesh_terms: D000328:Adult; D000368:Aged; D000700:Analgesics / Q000627:therapeutic use*; D002908:Chronic Disease; D015897:Comorbidity; D005260:Female; D005767:Gastrointestinal Diseases / Q000453:epidemiology; D006801:Humans; D006967:Hypersensitivity / Q000453:epidemiology; D007558:Italy / Q000453:epidemiology; D008297:Male; D001523:Mental Disorders / Q000453:epidemiology; D008875:Middle Aged; D008881:Migraine Disorders / Q000188:drug therapy* / Q000453:epidemiology / Q000503:physiopathology; D015995:Prevalence; D016896:Treatment Outcome; D014363:Tryptamines / Q000627:therapeutic use*
chemical_list: D000700:Analgesics; D014363:Tryptamines