Baroreflex Sensitivity in Relation to Clinical Characteristics in Subject Aged 40 to 80 YearsLouise Brinth1,2*, Kirsten Pors1, Tabassam Latif1, Andreas Kjær3 and Jesper Mehlsen1,2
- *Corresponding Author:
- Louise Brinth
Coordinating Research Centre
Frederiksberg Hospital, Frederiksberg, Denmark
E-mail: [email protected]
Received Date: April 25, 2014; Accepted Date: May 27, 2014; Published Date: June 07, 2014
Citation: Brinth L, Pors K, Latif T, Kjær A, Mehlsen J (2014) Baroreflex Sensitivity in Relation to Clinical Characteristics in Subject Aged 40 to 80 Years. J Hypertens 3:152. doi:10.4172/2167-1095.1000152
Copyright: © 2014 Brinth L, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Baroreflex function measured as baroreflex sensitivity (BRS) mirrors an integrated capacity of the autonomic nervous system. We aimed to assess the relationship between measures of BRS and age and relevant clinical characteristics.
80 subjects participating in the Copenhagen City Heart study (43 women) with a mean age of 59 ± 11 years (range 41-79 years) were included. Baroreceptor activity was quantified through the Valsalva manoeuvre (VM) and as a spontaneous function. BRS was tested against age, gender, smoking status, body size and predicted risk of coronary heart disease based on the Framingham score.
BRS was found to decline with age, but this change disappeared when correcting for the age related increase in systolic blood pressure. We found that the VM-derived indices of sympathetic vascular control declined with age as did the vagally controlled heart rate changes in response to deep breathing and VM. We could not demonstrate any correlation between BRS, smoking status, and body size when adjusting for age and gender, whereas spontaneous BRS was reduced with increasing Framingham risk score. Principal component analysis revealed three component explaining 69% of the total variance in our population comprising one component reflecting the sympathetic activity, the parasympathetic system, and the integrated spontaneous BRS, respectively. The parasympathetic component was the only one correlating with clinical characteristics of declining age, smoking habits, systolic blood pressure and Framingham score.
It is concluded that the parasympathetic and sympathetic parts of the baroreflex arch behave differently with respect to aging and cardiovascular risk factors. The most prominent changes are seen in cardiovagal control whereas the effects of age related changes in sympathetic vascular control are less noticeable. Our study supports the use of the cardiovagal part of the baroreflex arch as an indicator of cardiovascular risk.