title: Seasonal Variation, Cranial Autonomic Symptoms, and Functional Disability in Migraine: A Questionnaire-Based Study in Tertiary Care.
abstract: OBJECTIVE
  Seasonal variation of migraine attack frequency has been described as a phenomenon. We aimed to compare functional disability and the occurrence of cranial autonomic symptoms (CASs) in patients who reported a seasonal variation in their migraine attack frequency with those who did not.
  
  
  METHODS
  We conducted a questionnaire-based observational study on patients with migraine without aura who visited our institution from January 2005 to December 2013. Patient demographics, headache characteristics, and accompanying symptoms were recorded, and functional disability was evaluated by Migraine Disability Assessment (MIDAS) Questionnaire.
  
  
  RESULTS
  Of 4423 patients screened, 769 were eligible for analysis, and 104 (13.5%) of them reported seasonal variation. Several CAS features such as conjunctival injection (25.0% vs 14.0%), lacrimation (20.2% vs 10.8%), eyelid edema (20.2% vs 10.2%), forehead and facial sweating (22.1% vs 11.4%), and ptosis (23.1% vs 11.4%) were more prominent in this subset of patients. They showed higher MIDAS scores (15.4 ± 23.5) than the other migraineurs (10.4 ± 16.9), with a 1.77-fold increased risk (95% confidence interval 1.06-2.96) of severe functional disability (MIDAS score ≥21) after adjustment for age group, sex, headache frequency, intensity, and duration. The higher the number of CASs, the greater also was the proportion of patients with severe functional disability.
  
  
  CONCLUSIONS
  Patients who reported seasonal variation in migraine also reported more CASs and had more severe functional disability. The profound functional disability in the migraineurs reporting seasonal variation or CAS also provides direction for proactive clinical management in these patients.
authors.affiliation: Department of Neurology, Seoul National University Hospital, Seoul, South Korea.
authors.forename: Yong-Won
authors.initials: YW
authors.lastname: Shin
authors.affiliation: Department of Neurology, Seoul National University Hospital, Seoul, South Korea.
authors.forename: Hyun-Jung
authors.initials: HJ
authors.lastname: Park
authors.affiliation: Department of Neurology, Seoul National University Hospital, Seoul, South Korea.
authors.forename: Ji-Young
authors.initials: JY
authors.lastname: Shim
authors.affiliation: Department of Neurology, Seoul National University Hospital, Seoul, South Korea.
authors.forename: Min-Jung
authors.initials: MJ
authors.lastname: Oh
authors.affiliation: Department of Neurology, Seoul National University Hospital, Seoul, South Korea.|Protein Metabolism Medical & Neuroscience Research Center, College of Medicine, Seoul National University, Seoul, South Korea.
authors.forename: Manho
authors.initials: M
authors.lastname: Kim
mesh_terms: D000293:Adolescent; D000328:Adult; D001342:Autonomic Nervous System Diseases / Q000209:etiology*; D004185:Disability Evaluation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008881:Migraine Disorders / Q000150:complications* / Q000503:physiopathology*; D012621:Seasons; D011795:Surveys and Questionnaires; D063128:Tertiary Health Care; D055815:Young Adult
keywords: Migraine Disability Assessment; cluster headache; cranial autonomic symptom; migraine; seasonal