title: Dynamics of the cardiovascular autonomic regulation during orthostatic challenge is more relaxed in women.
abstract: Linear dynamic analysis of cardiovascular and respiratory time series was performed in healthy subjects with respect to gender by shifted short-term segments throughout a head-up tilt (HUT) test. Beat-to-beat intervals (BBI), systolic (SYS) and diastolic (DIA) blood pressure and respiratory interval (RESP) time series were acquired in 14 men and 15 women. In time domain (TD), the descending slope of the auto-correlation function (ACF) (BBI_a31cor) was more pronounced in women than in men (p<0.05) during the HUT test and considerably steeper (p<0.01) at the end of orthostatic phase (OP). The index SYS_meanNN was slightly but significantly lower (p<0.05) in women during the complete test, while higher respiratory frequency and variability (RESP_sdNN) were found in women (p<0.05), during 10-20 min after tilt-up. In frequency domain (FD), during baseline (BL), BBI-normalized low frequency (BBI_LFN) and BBI_LF/HF were slightly but significantly lower (p<0.05), while normalized high frequency (BBI_HFN) was significantly higher in women. These differences were highly significant from the first 5 min after tilt-up (p<0.01) and highly significant (p<0.001) during 10-14 min of OP. Findings revealed that men showed instantaneously a pronounced and sustained increase in sympathetic activity to compensate orthostatism. In women, sympathetic activity was just increased slightly with delayed onset without considerably affecting sympatho-vagal balance.
authors.affiliation: Universidad Autónoma Metropolitana, Electrical Engineering Department, 09340 Mexico City, Mexico.
authors.forename: Sina
authors.initials: S
authors.lastname: Reulecke
authors.affiliation: Universidad Autónoma Metropolitana, Electrical Engineering Department, 09340 Mexico City, Mexico.
authors.forename: Sonia
authors.initials: S
authors.lastname: Charleston-Villalobos
authors.affiliation: Institute of Innovative Health Technologies, Ernst-Abbe-Hochschule Jena, 07745 Jena, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Voss
authors.affiliation: Universidad Autónoma Metropolitana, Health Science Department, 09340 Mexico City, Mexico.
authors.forename: Ramón
authors.initials: R
authors.lastname: González-Camarena
authors.affiliation: National Institute of Cardiology, 14080 Mexico City, Mexico.
authors.forename: Jesús
authors.initials: J
authors.lastname: González-Hermosillo
authors.affiliation: Universidad Autónoma Metropolitana, Health Science Department, 09340 Mexico City, Mexico.
authors.forename: Mercedes
authors.initials: M
authors.lastname: Gaitán-González
authors.affiliation: National Institute of Cardiology, 14080 Mexico City, Mexico.
authors.forename: Guadalupe
authors.initials: G
authors.lastname: Hernández-Pacheco
authors.affiliation: Ernst-Abbe-Hochschule Jena, Department of Medical Engineering and Biotechnology, 07745 Jena, Germany.
authors.forename: Rico
authors.initials: R
authors.lastname: Schroeder
authors.affiliation: Universidad Autónoma Metropolitana, Electrical Engineering Department, 09340 Mexico City, Mexico.
authors.forename: Tomás
authors.initials: T
authors.lastname: Aljama-Corrales
mesh_terms: D001341:Autonomic Nervous System / Q000503:physiopathology*; D001794:Blood Pressure / Q000502:physiology*; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D011187:Posture; D056152:Respiratory Rate / Q000502:physiology*; D018667:Tilt-Table Test
keywords: autonomic regulation; blood pressure variability; heart rate variability; linear dynamic analysis; orthostatic stress