title: Cardiac parasympathetic dysfunction in the early phase of Parkinson's disease.
abstract: Cardiac parasympathetic function is strongly affected by aging. Although sympathetic dysfunction has been well documented in Parkinson's disease (PD), cardiac parasympathetic dysfunction has not been well studied. The objective of this study was to clarify the development of cardiac parasympathetic dysfunction in the early phase of PD and to explore the age-corrected correlation between cardiac parasympathetic dysfunction and cardiac sympathetic dysfunction. We reviewed 25 healthy controls and 56 patients with idiopathic PD of Hoehn and Yahr stages I-III. We evaluated cardiac parasympathetic function using the Valsalva ratio, the baroreflex sensitivity (BRS) and the coefficient of variation of RR intervals in the resting state (resting-CVRR) and during deep breathing (DB-CVRR). In addition, we measured cardiac123I-metaiodobenzylguanidine (MIBG) uptake to investigate the relationship between cardiac sympathetic and parasympathetic dysfunction in PD. Compared with healthy controls, patients with PD showed significantly decreased cardiac parasympathetic parameters (resting-CVRR 2.8 ± 1.3 vs. 1.7 ± 0.6%, p < 0.001; DB-CVRR 5.8 ± 2.3 vs. 3.8 ± 1.7%, p < 0.001; Valsalva ratio 1.52 ± 0.26 vs. 1.34 ± 0.17, p < 0.01; BRS 10.6 ± 9.5 vs. 5.0 ± 5.4 ms/mmHg, p < 0.01). In particular, resting-CVRR and DB-CVRR were significantly decreased in the early phase of PD. In age-corrected analyses, none of the parasympathetic indices correlated with the delayed cardiac123I-MIBG uptake. These observations indicate that cardiac parasympathetic dysfunction occurs in the early phase of PD, but not necessarily in parallel with cardiac sympathetic dysfunction.
authors.affiliation: Department of Neurology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho Showa-ku, Nagoya, 466-8550, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Suzuki
authors.affiliation: Department of Neurology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho Showa-ku, Nagoya, 466-8550, Japan. tomohiko@med.nagoya-u.ac.jp.
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Nakamura
authors.affiliation: Department of Pathophysiological Laboratory Science, 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, 65 Tsurumai-cho Showa-ku, Nagoya, 466-8550, Japan.
authors.forename: Miki
authors.initials: M
authors.lastname: Ueda
authors.affiliation: Department of Neurology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho Showa-ku, Nagoya, 466-8550, Japan.
authors.forename: Masahisa
authors.initials: M
authors.lastname: Katsuno
authors.affiliation: Department of Neurology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho Showa-ku, Nagoya, 466-8550, Japan. sobueg@med.nagoya-u.ac.jp.|Research Division of Dementia and Neurodegeneration Disease, Nagoya University Graduate School of Medicine, Nagoya, Japan. sobueg@med.nagoya-u.ac.jp.
authors.forename: Gen
authors.initials: G
authors.lastname: Sobue
mesh_terms: D019797:3-Iodobenzylguanidine; D000368:Aged; D000375:Aging / Q000502:physiology; D001342:Autonomic Nervous System Diseases / Q000188:drug therapy / Q000209:etiology / Q000503:physiopathology*; D001794:Blood Pressure; D001795:Blood Pressure Determination; D018450:Disease Progression; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D055414:Myocardial Perfusion Imaging; D010300:Parkinson Disease / Q000150:complications / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000503:physiopathology*; D019275:Radiopharmaceuticals; D012720:Severity of Illness Index; D018667:Tilt-Table Test; D014636:Valsalva Maneuver
chemical_list: D019275:Radiopharmaceuticals; D019797:3-Iodobenzylguanidine
keywords: Autonomic dysfunction; Autonomic nervous system; Cardiac 123I-metaiodobenzylguanidine scintigraphy; Cardiac parasympathetic dysfunction; Parkinson’s disease