title: Cardiovascular autonomic dysfunction in multiple sclerosis: a meta-analysis.
abstract: OBJECTIVE
  The definition of cardiovascular autonomic dysfunction in patients with multiple sclerosis is controversial. Thus, its true prevalence is unknown. We performed a systematic review and meta-analysis to compare the proportion of patients with multiple sclerosis that would be diagnosed with cardiovascular dysautonomia using a definition of at least one abnormal cardiac autonomic test vs. at least two abnormal studies.
  
  
  METHODS
  We searched PubMed, Embase, and Scopus from 1980 to December 2013 for publications reporting abnormal autonomic tests in patients with multiple sclerosis. We performed random-effects meta-analyses for calculating the proportion of patients diagnosed with autonomic dysfunction with both definitions.
  
  
  RESULTS
  We included 16 studies comprising 611 patients with multiple sclerosis, assessing ≥3 cardiovascular autonomic tests. The proportion of patients with autonomic dysfunction was two-fold higher (p=0.006) when using the definition of only one abnormal autonomic test (42.1%) compared to that using at least two abnormal results (18.8%).
  
  
  CONCLUSIONS
  We found a wide variation in the proportion of patients with multiple sclerosis diagnosed with cardiovascular dysautonomia by using the two definitions. Consensus is needed to define autonomic dysfunction in patients with multiple sclerosis. In the meantime, we encourage investigators to report results using both thresholds.
authors: Department of Clinical Neurological Sciences, London Health Sciences Centre. Western, University, London, ON, Canada.
authors: Juan Manuel
authors: JM
authors: Racosta
authors: Department of Clinical Neurological Sciences, London Health Sciences Centre. Western, University, London, ON, Canada.
authors: Luciano A
authors: LA
authors: Sposato
authors: Department of Clinical Neurological Sciences, London Health Sciences Centre. Western, University, London, ON, Canada.
authors: Sarah A
authors: SA
authors: Morrow
authors: Ivey Business School, Western University, London, ON, Canada.
authors: Lauren
authors: L
authors: Cipriano
authors: Department of Clinical Neurological Sciences, London Health Sciences Centre. Western, University, London, ON, Canada.
authors: Kurt
authors: K
authors: Kimpinski
authors: Department of Clinical Neurological Sciences, London Health Sciences Centre. Western, University, London, ON, Canada.
authors: Kurt
authors: K
authors: Kimpiski
authors: Department of Clinical Neurological Sciences, London Health Sciences Centre. Western, University, London, ON, Canada. Electronic address: marcelo.kremenchutzky@lhsc.on.ca.
authors: Marcelo
authors: M
authors: Kremenchutzky
mesh_terms: D000328:Adult; D002318:Cardiovascular Diseases / Q000175:diagnosis / Q000209:etiology*; D005260:Female; D006801:Humans; D008297:Male; D009103:Multiple Sclerosis / Q000150:complications*; D009460:Neurologic Examination / Q000379:methods; D054969:Primary Dysautonomias / Q000175:diagnosis / Q000209:etiology*
keywords: Autonomic dysfunction; Autonomic nervous system; Diagnosis; Multiple sclerosis