title: Cardiovascular control in women with fibromyalgia syndrome: do causal methods provide nonredundant information compared with more traditional approaches?
abstract: The cardiovascular autonomic control and the baroreflex sensitivity (BRS) have been widely studied in fibromyalgia syndrome (FMS) patients through the computation of linear indices of spontaneous heart period (HP) and systolic arterial pressure (SAP) variabilities. However, there are many methodological difficulties regarding the quantification of BRS by the traditional indices especially in relation to the issue of causality. This difficulty has been directly tackled via a model-based approach describing the closed-loop HP-SAP interactions and the exogenous influences of respiration. Therefore, we aimed to assess whether the BRS assessed by the model-based causal closed-loop approach during supine and active standing in patients with FMS could provide complementary information to those obtained by traditional indices based on time and frequency domains. The findings of this study revealed that, at difference with the traditional methods to quantify BRS, the causality analysis applied to the HP, SAP, and respiratory series, through the model-based closed-loop approach, detected lower BRS in supine position, as well as a blunted response to the orthostatic stimulus in patients with FMS compared with healthy control subjects. Also, the strength of the causal relation from SAP to HP (i.e., along the cardiac baroreflex) increased during the active standing only in the control subjects. The model-based closed-loop approach proved to provide important complementary information about the cardiovascular autonomic control in patients with FMS.
authors.affiliation: Department of Physical Therapy, Federal University of São Carlos, São Carlos, Brazil; beto.zam@gmail.com.
authors.forename: Antonio Roberto
authors.identifier: http://orcid.org/0000-0002-7480-3047
authors.initials: AR
authors.lastname: Zamunér
authors.affiliation: Department of Biomedical Sciences for Health, University of Milan, Milan, Italy; Istituti di Ricovero e Cura a Carattere Scientifico Galeazzi Orthopedic Institute, Milan, Italy;
authors.forename: Alberto
authors.identifier: http://orcid.org/0000-0002-6720-9824
authors.initials: A
authors.lastname: Porta
authors.affiliation: Department of Physical Therapy, Federal University of São Carlos, São Carlos, Brazil;
authors.forename: Carolina Pieroni
authors.initials: CP
authors.lastname: Andrade
authors.affiliation: Department of Electronics Information and Bioengineering, Politecnico di Milano, Milan, Italy; and.
authors.forename: Andrea
authors.initials: A
authors.lastname: Marchi
authors.affiliation: Department of Physical Therapy, Federal University of São Carlos, São Carlos, Brazil;
authors.forename: Meire
authors.initials: M
authors.lastname: Forti
authors.affiliation: Internal Medicine, Humanitas Research Hospital, Rozzano, Biometra Department, University of Milan, Milan, Italy.
authors.forename: Raffaello
authors.initials: R
authors.lastname: Furlan
authors.affiliation: Internal Medicine, Humanitas Research Hospital, Rozzano, Biometra Department, University of Milan, Milan, Italy.
authors.forename: Franca
authors.initials: F
authors.lastname: Barbic
authors.affiliation: Department of Physical Therapy, Federal University of São Carlos, São Carlos, Brazil;
authors.forename: Aparecida Maria
authors.initials: AM
authors.lastname: Catai
authors.affiliation: Department of Physical Therapy, Federal University of São Carlos, São Carlos, Brazil;
authors.forename: Ester
authors.initials: E
authors.lastname: Silva
mesh_terms: D000328:Adult; D062186:Arterial Pressure; D001341:Autonomic Nervous System / Q000503:physiopathology*; D017704:Baroreflex; D002319:Cardiovascular System / Q000294:innervation*; D016022:Case-Control Studies; D004562:Electrocardiography; D005260:Female; D005356:Fibromyalgia / Q000175:diagnosis* / Q000503:physiopathology*; D006334:Heart Function Tests / Q000379:methods*; D006339:Heart Rate; D006801:Humans; D008875:Middle Aged; D008955:Models, Cardiovascular; D056888:Patient Positioning; D011237:Predictive Value of Tests; D012737:Sex Factors; D019722:Sphygmomanometers; D016683:Supine Position; D013997:Time Factors
keywords: autonomic nervous system; baroreflex; causality; fibromyalgia; modeling