title: Cardiovascular and renin responses to head-up tilt tests in parkinsonism.
abstract: OBJECTIVE
  We investigated cardiovascular and renin responses to head-up tilt tests in patients with Parkinson's disease (PD), multiple system atrophy (MSA), and in controls to determine variables for the assignment of parkinsonism to the potential underlying neurologic condition.
  
  
  METHODS
  Sequential changes in sympathetic-mediated circulatory variables such as heart rate, blood pressure, and plasma renin concentration during head-up tilt tests were studied in 14 patients with PD and 11 patients with MSA. Twelve subjects with normal autonomic functions were studied as controls.
  
  
  RESULTS
  Head-up tilt resulted in significant differences in blood pressure and heart rate responses between PD, MSA, and controls. The baseline plasma renin concentration was significantly lower in MSA than in controls. Twenty min head-up tilt revealed significant differences in plasma renin concentration between PD, MSA, and controls.
  
  
  CONCLUSIONS
  We conclude that investigating sequential changes in mean arterial blood pressure, heart rate, and plasma renin concentration during head-up tilt test can potentially support differential diagnosis of PD and MSA.
authors.affiliation: Max Planck Institute of Psychiatry, Clinical Institute, Neurology, Munich, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Plaschke
authors.forename: J
authors.initials: J
authors.lastname: Schwarz
authors.forename: H
authors.initials: H
authors.lastname: Dahlheim
authors.forename: H
authors.initials: H
authors.lastname: Backmund
authors.forename: C
authors.initials: C
authors.lastname: Trenkwalder
mesh_terms: D000328:Adult; D000368:Aged; D001341:Autonomic Nervous System / Q000503:physiopathology; D001794:Blood Pressure / Q000502:physiology; D003937:Diagnosis, Differential; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D019578:Multiple System Atrophy / Q000175:diagnosis / Q000503:physiopathology*; D009849:Olivopontocerebellar Atrophies / Q000175:diagnosis / Q000503:physiopathology; D010300:Parkinson Disease / Q000175:diagnosis / Q000503:physiopathology*; D010302:Parkinson Disease, Secondary / Q000175:diagnosis / Q000503:physiopathology*; D012083:Renin / Q000097:blood*; D018667:Tilt-Table Test
chemical_list: D012083:Renin