title: (123)I-MIBG myocardial scintigraphy and neurocirculatory abnormalities in patients with dementia with Lewy bodies and Alzheimer's disease.
abstract: BACKGROUND
  Although adoption of new clinical criteria for dementia with Lewy bodies (DLB) leads to an increase in the proportion of patients diagnosed with probable DLB, the sensitivity of clinical diagnostic criteria of DLB is low, and there are no generally accepted clinical or imaging biomarkers to distinguish DLB from other types of dementia. In this study, we investigated whether neurocirculatory abnormalities and cardiac sympathetic denervation differed in controls and patients with subjective memory impairment (SMI), mild cognitive impairment (MCI), Alzheimer's disease (AD), and DLB. We also assessed whether spontaneous features of Parkinsonism might be related to the neurocirculatory abnormalities and cardiac sympathetic denervation found in DLB.
  
  
  METHODS
  Twenty-two consecutive patients with probable DLB were enrolled in this study; 25 age-matched controls, 14 SMI, 24 MCI, and 37 AD patients were also evaluated. Metaiodobenzylguanidine (MIBG) uptake was assessed using the ratio of the heart to the upper mediastinum (H/M ratio), and orthostatic vital signs and ambulatory 24-hour blood pressure monitoring values were recorded.
  
  
  RESULTS
  The mean H/M ratio was significantly lower and the proportion of orthostatic hypotension was higher in patients with DLB than in controls, SMI, MCI and AD patients. In patients with DLB, spontaneous Parkinsonism was not related to the degree of cardiac sympathetic denervation nor did it influence neurocirculatory abnormalities.
  
  
  CONCLUSIONS
  Our results suggest that MIBG scintigraphy and autonomic function tests may be useful for distinguishing between DLB and AD in clinical practice. Myocardial postganglionic sympathetic denervation and autonomic dysfunctions are present in patients with DLB regardless of spontaneous Parkinsonism.
authors.affiliation: Department of Neurology, College of Medicine, The Catholic University of Korea, South Korea. Electronic address: neuronet@catholic.ac.kr.
authors.forename: Joong-Seok
authors.initials: JS
authors.lastname: Kim
authors.affiliation: Department of Neurology, College of Medicine, The Catholic University of Korea, South Korea.
authors.forename: Hyung-Eun
authors.initials: HE
authors.lastname: Park
authors.affiliation: Department of Neurology, College of Medicine, The Catholic University of Korea, South Korea.
authors.forename: Yoon-Sang
authors.initials: YS
authors.lastname: Oh
authors.affiliation: Department of Neurology, College of Medicine, The Catholic University of Korea, South Korea.
authors.forename: In-Uk
authors.initials: IU
authors.lastname: Song
authors.affiliation: Department of Neurology, College of Medicine, The Catholic University of Korea, South Korea.
authors.forename: Dong-Won
authors.initials: DW
authors.lastname: Yang
authors.affiliation: Department of Neurology, College of Medicine, The Catholic University of Korea, South Korea.
authors.forename: Jeong-Wook
authors.initials: JW
authors.lastname: Park
authors.affiliation: Department of Neurology, College of Medicine, The Catholic University of Korea, South Korea.
authors.forename: Kwang-Soo
authors.initials: KS
authors.lastname: Lee
mesh_terms: D019797:3-Iodobenzylguanidine; D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000000981:diagnostic imaging* / Q000523:psychology; D060825:Cognitive Dysfunction / Q000000981:diagnostic imaging / Q000523:psychology; D005260:Female; D006801:Humans; D007024:Hypotension, Orthostatic / Q000000981:diagnostic imaging* / Q000523:psychology; D007457:Iodine Radioisotopes; D020961:Lewy Body Disease / Q000000981:diagnostic imaging* / Q000523:psychology; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals
chemical_list: D007457:Iodine Radioisotopes; D019275:Radiopharmaceuticals; D019797:3-Iodobenzylguanidine
keywords: (123)I-metaiodobenzylguanidine myocardial scintigraphy; Alzheimer's disease; Autonomic dysfunction; Dementia with Lewy bodies; Nondipping; Orthostatic hypotension