Cardiovascular dysautonomia in de novo Parkinson's disease without orthostatic hypotension.
BACKGROUND
Clinical symptoms of Parkinson's disease (PD) include not only motor distress, but also autonomic dysfunction.


OBJECTIVE
To study the characteristics of subclinical autonomic nervous dysfunction in de novo PD without orthostatic hypotension (OH).


METHODS
Autonomic nervous function including cardiac sympathetic gain was evaluated on the basis of cardiac radioiodinated metaiodobenzylguanidine (MIBG) uptake, the response to the Valsalva maneuver, and spectral analyses of the RR interval and blood pressure in 20 patients with de novo PD without OH.


RESULTS
Decreased cardiac MIBG uptake was found even in patients with PD without OH. Hemodynamic studies using the Valsalva maneuver revealed that patients with PD without OH had preserved baroreceptor reflex sensitivity in phase II and phase IV. Blood pressures normally responded in early and late phase II, but not in phase IV. Blood pressure recovery time was slightly reduced in patients with PD without OH when compared with the value in controls. The low frequency component of the RR interval and systolic blood pressure and the ratio of RR-LF to RR-HF in de novo PD without OH were significantly reduced when compared with the control values, whereas the high frequency component of the RR interval did not differ significantly.


CONCLUSIONS
These results show that latent cardiac and vasomotor sympathetic dysfunction but not parasympathetic dysfunction is already present in early stage de novo PD, even without orthostatic hypotension.
Oka
H
H
Department of Neurology, Daisan Hospital, The Jikei University School of Medicine, Izumihoncyo, Komae-shi, Tokyo, Japan.
Toyoda
C
C
Department of Neurology, Daisan Hospital, The Jikei University School of Medicine, Izumihoncyo, Komae-shi, Tokyo, Japan.
Yogo
M
M
Department of Neurology, Daisan Hospital, The Jikei University School of Medicine, Izumihoncyo, Komae-shi, Tokyo, Japan.
Mochio
S
S
Department of Neurology, Daisan Hospital, The Jikei University School of Medicine, Izumihoncyo, Komae-shi, Tokyo, Japan.
D019797:3-Iodobenzylguanidine; D000368:Aged; D001794:Blood Pressure / Q000502:physiology; D002319:Cardiovascular System / Q000000981:diagnostic imaging / Q000503:physiopathology; D005260:Female; D015637:Gated Blood-Pool Imaging; D006321:Heart / Q000000981:diagnostic imaging / Q000294:innervation / Q000503:physiopathology; D006801:Humans; D007024:Hypotension, Orthostatic; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000150:complications* / Q000000981:diagnostic imaging / Q000503:physiopathology*; D054969:Primary Dysautonomias / Q000000981:diagnostic imaging / Q000209:etiology* / Q000503:physiopathology*; D014636:Valsalva Maneuver / Q000502:physiology
D019797:3-Iodobenzylguanidine