Ethnicity, Sex, and Vagal Activity: Differences in Hemodynamics Underlying Long-Term Blood Pressure Regulation

Bibliographic Details
Main Author: Williams, DeWayne P.
Language:English
Published: The Ohio State University / OhioLINK 2017
Subjects:
Online Access:http://rave.ohiolink.edu/etdc/view?acc_num=osu1500640025670825
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spelling ndltd-OhioLink-oai-etd.ohiolink.edu-osu15006400256708252021-08-03T07:03:35Z Ethnicity, Sex, and Vagal Activity: Differences in Hemodynamics Underlying Long-Term Blood Pressure Regulation Williams, DeWayne P. Psychology Physiological Psychology Health blood pressure hypertension ethnic differences sex differences autonomic activity Hypertension, or high blood pressure, is a leading cause for mortality and morbidity worldwide. When split by ethnicity, African American (AA) individuals are at a greater risk for the development of hypertension compared to Caucasian American (CA) individuals. It is thought that over the course of hypertension, higher cardiac output is typically responsible for initially higher BP, and as hypertension progresses, cardiac output normalizes and total peripheral resistance (TPR) increases. Autonomic nervous system (ANS) activity is thought to underlie the development of hypertension, including the aforementioned hemodynamic changes. Ethnic differences have been found in resting ANS and hemodynamic activity, and are thought to potentially underlie ethnic disparities. Moreover, sex differences in resting ANS activity and the development of hypertension have been reported. One common theme underlying ethnic and sex differences in ANS control is vagally-mediated (vmHRV), which is widely recognized as an index of parasympathetic nervous system (PNS) activity, and serves as an independent risk factor for hypertension. However, research has yet to examine how ethnicity, sex, and vmHRV may interact to produce different patterns of hemodynamics in long-term BP regulation. In the following study, prospective methods were used to investigate this complex relationship. I investigated hemodynamic patterns over the course of six years, with physiological measures taken at two time points: (1) Baseline/initial visit (“Time 1”) and; (2) follow up visit on an average of 6 years later (“Time 2”). I considered hemodynamic patterns from “Time 1” to “Time 2” in the full sample, in addition to split by ethnicity (AAs and CAs), by sex (males and females), and vmHRV at “Time 1”. A median split was conducted on “Time 1” vmHRV to create high and low vmHRV groups to show the impact of relative high and low vmHRV on hemodynamics over time. Results showed that in normotensive individuals, CAs show a relative normal aging of the cardiovascular system over time, characterized by increased BP over time via increased cardiac output and stable or decreased TPR, a pattern seen especially in CA males with higher vmHRV. In contrast, AAs showed a more deleterious pattern of cardiovascular activity, marked by increased BP via increases in TPR, a pattern seen especially in AA females with lower vmHRV. Overall these data suggest a similar outcome of higher BP, however this is achieved via different hemodynamic mechanisms as a function of ethnicity, sex, and resting PNS activity as indexed by baseline vmHRV. Based on these factors, implications for psychophysiological function, in addition to the development and treatment of hypertension, will be discussed. 2017 English text The Ohio State University / OhioLINK http://rave.ohiolink.edu/etdc/view?acc_num=osu1500640025670825 http://rave.ohiolink.edu/etdc/view?acc_num=osu1500640025670825 unrestricted This thesis or dissertation is protected by copyright: all rights reserved. It may not be copied or redistributed beyond the terms of applicable copyright laws.
collection NDLTD
language English
sources NDLTD
topic Psychology
Physiological Psychology
Health
blood pressure
hypertension
ethnic differences
sex differences
autonomic activity
spellingShingle Psychology
Physiological Psychology
Health
blood pressure
hypertension
ethnic differences
sex differences
autonomic activity
Williams, DeWayne P.
Ethnicity, Sex, and Vagal Activity: Differences in Hemodynamics Underlying Long-Term Blood Pressure Regulation
author Williams, DeWayne P.
author_facet Williams, DeWayne P.
author_sort Williams, DeWayne P.
title Ethnicity, Sex, and Vagal Activity: Differences in Hemodynamics Underlying Long-Term Blood Pressure Regulation
title_short Ethnicity, Sex, and Vagal Activity: Differences in Hemodynamics Underlying Long-Term Blood Pressure Regulation
title_full Ethnicity, Sex, and Vagal Activity: Differences in Hemodynamics Underlying Long-Term Blood Pressure Regulation
title_fullStr Ethnicity, Sex, and Vagal Activity: Differences in Hemodynamics Underlying Long-Term Blood Pressure Regulation
title_full_unstemmed Ethnicity, Sex, and Vagal Activity: Differences in Hemodynamics Underlying Long-Term Blood Pressure Regulation
title_sort ethnicity, sex, and vagal activity: differences in hemodynamics underlying long-term blood pressure regulation
publisher The Ohio State University / OhioLINK
publishDate 2017
url http://rave.ohiolink.edu/etdc/view?acc_num=osu1500640025670825
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