title: Abnormal Cerebrovascular Reactivity in Patients with Parkinson's Disease.
abstract: Background. Orthostatic hypotension (OH) is an important nonmotor manifestation of Parkinson's disease (PD). Changes in cerebrovascular reactivity may contribute to this manifestation and can be monitored using transcranial Doppler. Objective. To identify possible changes in cerebrovascular reactivity in patients with OH. Methods. Twenty-two individuals were selected and divided into three groups: with and without OH and controls. Transcranial Doppler was used to assess basal mean blood flow velocity, postapnea mean blood flow velocity, percentage increase in mean blood flow velocity, and cerebrovascular reactivity as measured by the breath-holding index. Results. PD patients had lower values of basal velocity (p = 0.019), postapnea velocity (p = 0.0015), percentage increase in velocity (p = 0.039), and breath-holding index (p = 0.04) than the controls. Patients with OH had higher values of basal velocity (p = 0.09) and postapnea velocity (p = 0.19) but lower values of percentage increase in velocity (p = 0.22) and breath-holding index (p = 0.32) than patients without OH. Conclusions. PD patients present with abnormalities in a compensatory mechanism that regulates cerebral blood flow. OH could be an indicator of these abnormalities.
authors.affiliation: State University of Ponta Grossa, Avenida General Carlos Cavalcanti 4748, 84030-900 Ponta Grossa, PR, Brazil.
authors.forename: Carlos Henrique Ferreira
authors.initials: CH
authors.lastname: Camargo
authors.affiliation: State University of Ponta Grossa, Avenida General Carlos Cavalcanti 4748, 84030-900 Ponta Grossa, PR, Brazil.
authors.forename: Eduardo Antunes
authors.initials: EA
authors.lastname: Martins
authors.affiliation: Hospital de Clínicas, Federal University of Paraná, Rua General Carneiro 181, 80060-900 Curitiba, PR, Brazil.
authors.forename: Marcos Christiano
authors.initials: MC
authors.lastname: Lange
authors.affiliation: State University of Ponta Grossa, Avenida General Carlos Cavalcanti 4748, 84030-900 Ponta Grossa, PR, Brazil.
authors.forename: Henrique Alvaro
authors.initials: HA
authors.lastname: Hoffmann
authors.affiliation: State University of Ponta Grossa, Avenida General Carlos Cavalcanti 4748, 84030-900 Ponta Grossa, PR, Brazil.
authors.forename: Jissa Jeanete
authors.initials: JJ
authors.lastname: Luciano
authors.affiliation: State University of Ponta Grossa, Avenida General Carlos Cavalcanti 4748, 84030-900 Ponta Grossa, PR, Brazil.
authors.forename: Marcelo Rezende
authors.initials: MR
authors.lastname: Young Blood
authors.affiliation: State University of Ponta Grossa, Avenida General Carlos Cavalcanti 4748, 84030-900 Ponta Grossa, PR, Brazil.
authors.forename: Marcelo Derbli
authors.initials: MD
authors.lastname: Schafranski
authors.affiliation: State University of Ponta Grossa, Avenida General Carlos Cavalcanti 4748, 84030-900 Ponta Grossa, PR, Brazil.
authors.forename: Marcelo Machado
authors.initials: MM
authors.lastname: Ferro
authors.affiliation: State University of Ponta Grossa, Avenida General Carlos Cavalcanti 4748, 84030-900 Ponta Grossa, PR, Brazil.
authors.forename: Edmar
authors.initials: E
authors.lastname: Miyoshi