title: Postural orthostatic tachycardia syndrome associated with multiple sclerosis.
abstract: BACKGROUND
  The aim of this study was to determine if there is a difference in the frequency of postural orthostatic tachycardia syndrome (POTS) in patients with multiple sclerosis (MS) compared to patients with symptoms of orthostatic intolerance and with no evidence of MS or other neurological illness.
  
  
  METHODS
  We analyzed data gathered from 293 patients who underwent the head-up tilt table test protocol. Group 1 included prospectively analyzed 112 with MS and group 2 included retrospectively analyzed 181 patients who were evaluated because of symptoms of orthostatic intolerance, and with no evidence of MS or other neurological illness. If POTS was identified the head-up tilt table test was repeated and supine as well as standing serum epinephrine and norepinephrine were determined.
  
  
  RESULTS
  POTS was identified in 39 patients: 21 (19%) in the MS group comparing to 18 (10%) in the non MS group (p=0.035). There was no difference between groups in the occurrence of POTS associated syncope (p=0.52). There was no difference between groups in the epinephrine or norepinephrine in supine and standing positions. While both standing epinephrine and norepinephrine levels were significantly higher compared to levels in the supine position in the non MS group, only standing norepinephrine levels were significantly higher in the MS group.
  
  
  CONCLUSIONS
  The results of this study suggest that POTS is associated with MS.
authors.affiliation: University Hospital Center Zagreb, Department of Neurology, Referral Center for Demyelinating Diseases of the Central Nervous System, Kišpatićeva 12, Zagreb, Croatia.
authors.forename: Ivan
authors.initials: I
authors.lastname: Adamec
authors.forename: Mila
authors.initials: M
authors.lastname: Lovrić
authors.forename: Dinka
authors.initials: D
authors.lastname: Žaper
authors.forename: Anabella Karla
authors.initials: AK
authors.lastname: Barušić
authors.forename: Ivo
authors.initials: I
authors.lastname: Bach
authors.forename: Anamari
authors.initials: A
authors.lastname: Junaković
authors.forename: Antonija
authors.initials: A
authors.lastname: Mišmaš
authors.forename: Mario
authors.initials: M
authors.lastname: Habek
mesh_terms: D000328:Adult; D001794:Blood Pressure; D015331:Cohort Studies; D017523:Croatia / Q000453:epidemiology; D004837:Epinephrine / Q000097:blood; D005260:Female; D006339:Heart Rate; D006785:Hospitals, University; D006801:Humans; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000097:blood / Q000150:complications / Q000503:physiopathology*; D009638:Norepinephrine / Q000097:blood; D054971:Orthostatic Intolerance / Q000097:blood / Q000150:complications / Q000503:physiopathology*; D054972:Postural Orthostatic Tachycardia Syndrome / Q000150:complications / Q000453:epidemiology / Q000503:physiopathology*; D011446:Prospective Studies; D012189:Retrospective Studies; D016683:Supine Position; D013575:Syncope / Q000209:etiology; D018667:Tilt-Table Test
chemical_list: D009638:Norepinephrine; D004837:Epinephrine