Motivation
Soluble urokinase plasminogen activator receptor (suPAR) is a known inflammatory marker, which is
found in various body fluids. SuPAR reflects the immune and pro–inflammatory status of patients caused
by HIV and tuberculosis, amongst others. However, recent studies have shown that suPAR is related to
cardiovascular function. The cardiovascular health of the black South African population is a major
health concern as this group suffers mostly from hypertension and stroke, leading to an alarming increase
in cardiovascular morbidity and mortality. SuPAR may be able to contribute to early detection and
prevention of cardiovascular diseases. No studies regarding the associations of suPAR with
cardiovascular function have been investigated on black South Africans.
Objectives
To investigate suPAR as a possible marker of cardiovascular function in African and Caucasian men and
women, by determining possible gender and ethnic–specific associations of suPAR with cardiovascular
function.
Methodology
There were 207 African and 314 Caucasian men and women (aged 20–79 yrs.) included in this study.
High–sensitivity C–reactive protein, glucose, lipids and creatinine were determined in fasting serum and
suPAR was analyzed in plasma samples. Blood pressure was measured using the OMRON apparatus
(HEM–747), with a 5–min rest interval between measurements. The Finometer device was used to
determine the Windkessel compliance and the carotid dorsalis–pedis pulse wave velocity (PWV) was
measured with the Complior (SP acquisition system) on the left side of each subject in the supine
position. The means, adjusted means and proportions were compared between the groups by using
independent t–tests, analysis of co–variance and the chi–square test, respectively. Associations were
investigated between cardiovascular variables and suPAR using single and multiple regression analyses
with either pulse wave velocity, systolic blood pressure, diastolic blood pressure or Windkessel
compliance as dependent variable. Covariates included were age, body mass index, smoking, alcohol use,
physical activity, glucose and high–density lipoprotein cholesterol.
Results and conclusion
SuPAR levels were significantly higher in Africans (P<0.001) compared to Caucasians. After adjusting
for body mass index, suPAR increased significantly with age in all groups, except for African women. Moreover, the suPAR levels of African men and women were significantly higher than the Caucasians
within each age quartile. While adjusting for age and body mass index, the cardiovascular profiles of the
African and Caucasian men were less favourable compared to women, but suPAR levels were
significantly higher in Caucasian women compared to men. In single regression, various measures of
cardiovascular function correlated with suPAR in African men and Caucasian men and women. After
adjusting for confounders the associations disappeared in Caucasian women, and remained nonsignificant
in the African women. However, the association between PWV and suPAR remained
significant in African men (B=0.19; P=0.030), while the association of systolic blood pressure (B=0.20;
P=0.017), diastolic blood pressure (B=0.17; P=0.020) and Windkessel compliance (B=–0.14; P=0.004)
with suPAR remained significant in Caucasian men. In conclusion, Africans presented higher suPAR
levels compared to Caucasians, even when stratified by age. Gender specific associations indicated that
suPAR was associated with arterial stiffness in African and Caucasian men only, therefore, indicating that
suPAR could be a possible biomarker for predicting cardiovascular dysfunction. / Thesis (M.Sc. (Physiology))--North-West University, Potchefstroom Campus, 2011.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:nwu/oai:dspace.nwu.ac.za:10394/4950 |
| Date | January 2010 |
| Creators | Smith, Anélda |
| Publisher | North-West University |
| Source Sets | South African National ETD Portal |
| Detected Language | English |
| Type | Thesis |
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