title: Assessment of prevalence and pathological response to orthostatic provocation in patients with multiple sclerosis.
abstract: OBJECTIVE
  The aim of this study was to determine the prevalence of pathologic response to orthostatic challenge in patients with relapsing remitting multiple sclerosis (RRMS) and the difference of the response in patients in relapse and remission.
  
  
  METHODS
  We included 112 RRMS patients; group 1 included 53 patients in a relapse and group 2, 59 patients in remission. The head up tilt table test was used to provoke an orthostatic reaction.
  
  
  RESULTS
  71 (63%) patients (60.4% and 66% of relapse and remission subjects respectively) had a pathological response to orthostatic provocation. Syncope was found in 9 (17%) patients in group 1 compared to 22 (37.3%) in group 2 (p=0.014). Postural orthostatic tachycardia syndrome (POTS) was found in 17 (32%) patients in group 1 compared to 4 (6.8%) in group 2 (p=0.001). There was a significantly negative correlation between the Expanded Disability Status Scale (EDSS) and POTS (-0.201; p=0.034) and a positive correlation between the EDSS and syncope (0.190; p=0.044).
  
  
  CONCLUSIONS
  The prevalence of distinct types of orthostatic autonomic dysfunction in different phases of RRMS seems to be in direct correlation with the EDSS. Furthermore, certain autonomic dysfunctions of orthostasis, more specifically syncope and POTS, tend to be increased in remission and relapse respectively.
authors.affiliation: University Hospital Center Zagreb, Department of Neurology, Referral Center for Demyelinating Diseases of the Central Nervous System, Zagreb, Croatia.
authors.forename: Ivan
authors.initials: I
authors.lastname: Adamec
authors.forename: Ivo
authors.initials: I
authors.lastname: Bach
authors.forename: Anabella Karla
authors.initials: AK
authors.lastname: Barušić
authors.forename: Antonija
authors.initials: A
authors.lastname: Mišmaš
authors.forename: Mario
authors.initials: M
authors.lastname: Habek
mesh_terms: D000293:Adolescent; D000328:Adult; D001341:Autonomic Nervous System / Q000503:physiopathology; D004185:Disability Evaluation; D005260:Female; D006323:Heart Arrest / Q000503:physiopathology; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D007024:Hypotension, Orthostatic / Q000209:etiology / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000150:complications / Q000453:epidemiology / Q000503:physiopathology*; D054971:Orthostatic Intolerance / Q000453:epidemiology / Q000209:etiology / Q000503:physiopathology*; D011446:Prospective Studies; D013575:Syncope / Q000209:etiology / Q000503:physiopathology; D013610:Tachycardia / Q000209:etiology / Q000503:physiopathology; D018667:Tilt-Table Test; D055815:Young Adult