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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 32, No 1, January/February 2021
AFRICA
15
innovative approach by determining HRV and salivary stress
hormone levels upon provocation to substantiate SAM and
HPA activity, and (2) a clinical stress and stroke risk score.
Our findings contribute to the sparse information on neural
mechanisms and chronic stress-induced stroke risk in the human
brain–retina axis.
Conclusion
In response to low norepinephrine levels, a reflex increase
in sympathetic activity occurred, resulting in increased
norepinephrine levels and hypo-perfusion, potentiating risk for
retinal ganglion cell health. Concomitant HPA dysregulation
changed retinal vein dynamics as delayed recovery responses
reflected non-adaptation to stress. Indeed, constrained or
delayed venous recovery responses predicted chronic stress and
stroke risk.
The ethics on publishing scientific articles were followed. We gratefully
acknowledge the voluntary collaboration of the participants. The SABPA
study would not have been possible without the valuable contributions from
co-investigators and technical staff.
Funding was obtained from the North-West University and Education
Department, South Africa, South African Medical Research Council,
National Research Foundation, Roche Diagnostics, Heart and Stroke
Foundation, South Africa (HSFSA2019/01) and the Metabolic Syndrome
Institute, France. Any opinion, findings and conclusions or recommendations
expressed in this material are those of the author(s) and therefore funding
bodies do not accept any liability in regard thereto.
WV is chief executive officer of the Imedos Systems GmbH (Jena,
Germany) and a freelance researcher. The other authors declare that the
research was conducted in the absence of any commercial or financial rela-
tionships that could be construed as a potential conflict of interest.
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