title: Twenty-four-hour ambulatory blood pressure and heart rate profiles in diagnosing orthostatic hypotension in Parkinson's disease and multiple system atrophy.
abstract: Twenty-four-hour ambulatory blood pressure and heart rate monitoring (24-h ABPM) can provide vital information on circadian blood pressure (BP) profiles, which are commonly abnormal in Parkinson's disease with and without autonomic failure (PD + AF and PD) and multiple system atrophy (MSA). Twenty-four-hour ABPM has not been directly compared between these disorders regarding cardiovascular autonomic function. Our aim was to determine the usefulness of 24-h ABPM with diary compared to head-up tilting (HUT) in diagnosing orthostatic hypotension (OH) in these patients.
  
  
  
  Seventy-four patients (23 MSA, 18 PD + AF, 33 PD) underwent cardiovascular autonomic screening followed by 24-h ABPM with diary. Standing tests were included during 24-h ABPM. The sensitivity and specificity in detecting OH from the 24-h ABPM standing test were compared with HUT.
  
  
  
  There was no difference in OH during HUT between MSA and PD + AF (P > 0.05). There was a higher proportion of abnormal BP circadian rhythms in MSA and PD + AF compared to PD (P < 0.05) but not between MSA and PD + AF (P > 0.05). Patients were divided into groups with OH (OH+) and without OH (OH-) on HUT. Using the standing test during 24-h ABPM, a systolic BP fall of >20 mmHg showed a sensitivity and specificity of 82% and 100% (area under the curve 0.91, 95% confidence interval 0.84-0.98) in differentiating OH+ from OH-.
  
  
  
  Parkinson's disease with autonomic failure and MSA patients had similar circadian BP patterns suggesting that autonomic dysfunction influences abnormal BP circadian patterns similarly in these disorders. The higher sensitivity and specificity in detecting OH using a systolic BP fall of >20 mmHg compared to a diastolic BP fall of >10 mmHg during the standing test supports its usefulness to assess autonomic function in MSA and PD.
authors.affiliation: Autonomic Unit, National Hospital for Neurology and Neurosurgery (NHNN), London, UK.|Autonomic and Neurovascular Medicine Unit, Faculty of Medicine, Imperial College London at St Mary's Hospital, London, UK.
authors.forename: E
authors.initials: E
authors.lastname: Vichayanrat
authors.affiliation: Autonomic and Neurovascular Medicine Unit, Faculty of Medicine, Imperial College London at St Mary's Hospital, London, UK.|Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK.
authors.forename: D A
authors.initials: DA
authors.lastname: Low
authors.affiliation: Autonomic Unit, National Hospital for Neurology and Neurosurgery (NHNN), London, UK.|Autonomic and Neurovascular Medicine Unit, Faculty of Medicine, Imperial College London at St Mary's Hospital, London, UK.
authors.forename: V
authors.initials: V
authors.lastname: Iodice
authors.affiliation: Clinic for Neurology and Clinical Neurophysiology, Centre of Research in Clinical Medicine (ZFKM), Helios clinic Wuppertal, University of Witten/Herdecke, Wuppertal, Germany.
authors.forename: E
authors.initials: E
authors.lastname: Stuebner
authors.affiliation: Autonomic and Neurovascular Medicine Unit, Faculty of Medicine, Imperial College London at St Mary's Hospital, London, UK.
authors.forename: E M
authors.identifier: 0000-0002-6925-6747
authors.initials: EM
authors.lastname: Hagen
authors.affiliation: Autonomic Unit, National Hospital for Neurology and Neurosurgery (NHNN), London, UK.|Autonomic and Neurovascular Medicine Unit, Faculty of Medicine, Imperial College London at St Mary's Hospital, London, UK.
authors.forename: C J
authors.initials: CJ
authors.lastname: Mathias
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001341:Autonomic Nervous System / Q000503:physiopathology; D001794:Blood Pressure / Q000502:physiology*; D018660:Blood Pressure Monitoring, Ambulatory; D002319:Cardiovascular System / Q000503:physiopathology; D002940:Circadian Rhythm / Q000502:physiology; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D007024:Hypotension, Orthostatic / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D019578:Multiple System Atrophy / Q000150:complications / Q000503:physiopathology*; D010300:Parkinson Disease / Q000150:complications / Q000503:physiopathology*; D011187:Posture / Q000502:physiology; D018667:Tilt-Table Test
keywords: Parkinson's disease; autonomic failure; autonomic tests; cardiovascular autonomic function; multiple system atrophy