title: Hyposmia and cardiovascular dysautonomia correlatively appear in early-stage Parkinson's disease.
abstract: OBJECTIVE
  Olfactory dysfunction is considered to precede motor symptoms and early markers of Parkinson's disease (PD), while the relative time at which cardiovascular dysautonomia appears in PD is not well understood. To assess the appearance of cardiovascular dysautonomia in PD, we evaluated its relation to olfactory dysfunction in early-stage PD patients.
  
  
  METHODS
  Twenty-three non-demented PD patients within 2 years from the onset of motor symptoms were enrolled. We evaluated olfactory dysfunction by the Odor Stick Identification Test for Japanese (OSIT-J) and analyzed its relationship to the results of other cardiovascular autonomic tests and cardiac (123)I-metaiodobenzylguanidine (MIBG) scintigraphy.
  
  
  RESULTS
  There was a correlation between olfactory scores and increased blood pressure in both the norepinephrine (r = 0.75, p < 0.0001, n = 21) and dobutamine (r = 0.57, p = 0.0087, n = 20) infusion tests and cardiac MIBG uptake (r = 0.42, p = 0.049, n = 23). The fall in orthostatic blood pressure during the head-up tilt test was not correlated with the olfactory scores, but the Valsalva maneuver revealed that OSIT-J scores correlated with the pressure recovery time from phase III to the return of blood pressure to baseline (r = 0.54, p = 0.037, n = 15) and with the magnitude of blood pressure overshoot during phase IV (r = 0.67, p = 0.0016, n = 20).
  
  
  CONCLUSIONS
  Our results demonstrate that extensive components of the cardiovascular sympathetic system as well as the olfactory system are correlatively impaired in the early stage of PD, suggesting that degeneration of broad aspects of the cardiovascular sympathetic system occurs concurrently with olfactory system degeneration during the premotor phase of PD.
authors.affiliation: Department of Neurology, Nagoya University Graduate School of Medicine, Nagoya, Japan.
authors.forename: Yasuaki
authors.initials: Y
authors.lastname: Mizutani
authors.affiliation: Department of Neurology, Nagoya University Graduate School of Medicine, Nagoya, Japan; Department of Laboratory Medicine, Nagoya University Hospital, Nagoya, Japan.
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Nakamura
authors.affiliation: Department of Neurology, Nagoya University Graduate School of Medicine, Nagoya, Japan.
authors.forename: Akinori
authors.initials: A
authors.lastname: Okada
authors.affiliation: Department of Neurology, Nagoya University Graduate School of Medicine, Nagoya, Japan.
authors.forename: Junichiro
authors.initials: J
authors.lastname: Suzuki
authors.affiliation: Department of Neurology, Nagoya University Graduate School of Medicine, Nagoya, Japan.
authors.forename: Hirohisa
authors.initials: H
authors.lastname: Watanabe
authors.affiliation: Department of Neurology, Nagoya University Graduate School of Medicine, Nagoya, Japan; Department of Pathophysiological Laboratory Sciences, Nagoya University Graduate School of Medicine, Nagoya, Japan.
authors.forename: Masaaki
authors.initials: M
authors.lastname: Hirayama
authors.affiliation: Department of Neurology, Nagoya University Graduate School of Medicine, Nagoya, Japan. Electronic address: sobueg@med.nagoya-u.ac.jp.
authors.forename: Gen
authors.initials: G
authors.lastname: Sobue
mesh_terms: D000328:Adult; D000368:Aged; D001342:Autonomic Nervous System Diseases / Q000150:complications / Q000209:etiology*; D002318:Cardiovascular Diseases / Q000150:complications / Q000209:etiology*; D004192:Discrimination, Psychological / Q000502:physiology; D005260:Female; D006146:Guanidines; D006801:Humans; D007456:Iodine Isotopes; D008297:Male; D008875:Middle Aged; D009812:Odorants; D000857:Olfaction Disorders / Q000175:diagnosis / Q000209:etiology*; D010300:Parkinson Disease / Q000150:complications*; D012903:Smell / Q000502:physiology; D014636:Valsalva Maneuver / Q000502:physiology
chemical_list: D006146:Guanidines; D007456:Iodine Isotopes; C117872:benzylguanidine
keywords: Cardiac (123)I-metaiodobenzylguanidine scintigraphy; Cardiovascular dysautonomia; OSIT-J; Olfactory dysfunction; Parkinson's disease