title: Cardiovascular autonomic dysfunction in dementia with Lewy bodies and Parkinson's disease.
abstract: OBJECTIVE
  We estimated the extent and pattern of cardiovascular autonomic dysfunction in dementia with Lewy bodies (DLB) as compared with that in Parkinson's disease (PD).
  
  
  METHODS
  We performed meta-iodobenzylguanidine ((123)I-MIBG) scintigraphy of the heart and hemodynamic autonomic function testing using the Valsalva maneuver in 27 patients with DLB, 46 with PD, and 20 controls.
  
  
  RESULTS
  (123)I-MIBG uptakes in DLB were reduced as compared with those in control and PD. Hemodynamic studies revealed that DLB had decreased baroreceptor reflex and reduced responses of SBP in phases II and IV as compared with PD and control. SBP responses on standing and the difference in plasma norepinephrine (NE) concentrations between supine and standing positions were reduced in PD as compared with those in control. Furthermore, SBP responses on standing, plasma NE concentrations in supine and standing positions, and the difference in plasma NE concentrations between these positions were significantly lower in DLB than in PD and control. Plasma NE concentrations in DLB with orthostatic hypotension (OH) were lower than that in DLB without OH, although some patients who had DLB with orthostatic hypotension had relatively normal plasma NE levels.
  
  
  CONCLUSIONS
  Cardiovascular autonomic dysfunction is more severe in DLB than in PD and is usually caused by the loss of postganglionic sympathetic nervous function, although dysautonomia in some patients with DLB may result from preganglionic dysfunction.
authors.affiliation: Department of Neurology, Jikei University School of Medicine, 3-25-8, Nishi-shinbashi, Tokyo, 105-8461, Japan. h.oka@jikei.ac.jp
authors.forename: Hisayoshi
authors.initials: H
authors.lastname: Oka
authors.forename: Masayo
authors.initials: M
authors.lastname: Morita
authors.forename: Kenji
authors.initials: K
authors.lastname: Onouchi
authors.forename: Masayuki
authors.initials: M
authors.lastname: Yoshioka
authors.forename: Soichiro
authors.initials: S
authors.lastname: Mochio
authors.forename: Kiyoharu
authors.initials: K
authors.lastname: Inoue
mesh_terms: D019797:3-Iodobenzylguanidine; D000368:Aged; D000369:Aged, 80 and over; D001158:Arteries / Q000294:innervation / Q000503:physiopathology; D001342:Autonomic Nervous System Diseases / Q000000981:diagnostic imaging / Q000209:etiology* / Q000503:physiopathology*; D017704:Baroreflex / Q000502:physiology; D002318:Cardiovascular Diseases / Q000000981:diagnostic imaging / Q000209:etiology* / Q000503:physiopathology*; D002320:Cardiovascular Physiological Phenomena; D005260:Female; D006321:Heart / Q000294:innervation / Q000503:physiopathology; D006801:Humans; D007024:Hypotension, Orthostatic / Q000000981:diagnostic imaging / Q000209:etiology / Q000503:physiopathology; D007457:Iodine Radioisotopes; D020961:Lewy Body Disease / Q000150:complications*; D008297:Male; D008875:Middle Aged; D009638:Norepinephrine / Q000097:blood; D010300:Parkinson Disease / Q000150:complications*; D011877:Radionuclide Imaging; D012021:Reflex, Abnormal / Q000502:physiology; D017779:Sympathetic Fibers, Postganglionic / Q000378:metabolism / Q000503:physiopathology
chemical_list: D007457:Iodine Radioisotopes; D019797:3-Iodobenzylguanidine; D009638:Norepinephrine