Introduction: Increased hemodynamic responses to psychological stress have been associated with risk of hypertension and other adverse cardiovascular outcomes. African Americans (AA) have more hypertension and worse cardiovascular outcomes than other ethnic groups. Heightened hemodynamic responses to stress may play a role. Our hypothesis was that AA would have significantly increased hemodynamic reactivity to a standardized mental stress as compared to Non-African Americans (NAA).
Methods: We evaluated 693 patients (209 AA) with confirmed coronary heart disease (CHD), who underwent a standardized mental stress challenge. Heart rate (HR), systolic blood pressure (SBP) and diastolic blood pressure (DBP) were obtained during a resting period, a speaking task, and a recovery period. The rate-pressure product (RPP) was calculated as SBP x HR. Hemodynamic reactivity with mental stress was evaluated as the difference in RPP at rest and during mental stress. Depressive symptoms were measured with the Beck Depression Inventory-II (BDI-II).
Results: As compared to NAA, AA patients were younger, had lower education and income, and higher prevalence of diabetes, obesity, hypertension, current smoking, and more depressive symptoms. AA patients had higher SBP and DBP during all three periods than NAA. However, hemodynamic reactivity with stress was significantly lower in AA than NAA (RPP reactivity 3108 vs 3591, p= 0.02), however after controlling for cardiovascular risk factors the association was attenuated and no longer significant (RPP reactivity 3423.69 vs 3541.78, p=0.6). There was a significant negative association between norepinephrine reactivity AA race after controlling for baseline norepinephrine, demographic factors, and cardiovascular history factors. The association was attenuated and lost statistical significance after addition of psychosocial factors.
Conclusions : AA patients with CHD, compared with NAA, have persistently elevated blood pressure throughout mental stress but tend to have lower hemodynamic and neuroendocrine reactivity to stress. Cardiovascular disease history factors explain much of the difference of the in stress responses. Whether blunted cardiovascular reactivity to stress is related to worse outcomes in AA needs further study.
Table of Contents
TABLE OF CONTENTSCHAPTER PAGE CHAPTERS CHAPTER 1--Introduction...1
CHAPTER 6--Conclusions...10REFERENCES...11 TABLES...13-20 FIGURE...21-22
About this Master's Thesis
|Committee Chair / Thesis Advisor|
|Race Differences in Hemodynamics and Cardiovascular Reactivity to Mental Stress ()||2018-08-28||