Ethnic differences in microvascular function in apparently healthy South African men and women

2.50
Hdl Handle:
http://hdl.handle.net/11287/593850
Title:
Ethnic differences in microvascular function in apparently healthy South African men and women
Authors:
Pienaar, P. R.; Micklesfield, L. K.; Gill, J. M.; Shore, Angela ( 0000-0003-3039-308x ) ; Gooding, K. M.; Levitt, N. S.; Lambert, E. V.
Abstract:
Microvascular dysfunction precedes the clinical manifestations of cardiovascular disease. Given the ethnic disparities in cardiovascular disease, we aimed to investigate ethnic differences in microvascular endothelial function in a group of young (18-33 years old), apparently healthy individuals (n = 33, nine Black African, 12 mixed ancestry and 12 Caucasian). Microvascular endothelium-dependent and -independent function was assessed by laser Doppler imagery and iontophoresis of ACh and sodium nitroprusside (SNP), respectively, adjusting for skin resistance. Microvascular reactivity was expressed as maximum absolute perfusion, percentage change from baseline and area under the curve (AUC). Skin resistance was significantly lower in the Caucasian group in response to ACh (Caucasian, mean 0.16 +/- 0.03 Omega versus Black, 0.21 +/- 0.04 Omega and mixed ancestry, 0.20 +/- 0.02 Omega, P < 0.01) and SNP (Caucasian, 0.08 +/- 0.01 Omega versus Black, 0.11 +/- 0.02 Omega and mixed ancestry, 0.12 +/- 0.01 Omega, P < 0.01). Microvascular function in response to ACh was significantly higher in the Caucasian group compared with the other two groups; however, after adjusting for skin resistance these differences were no longer significant. Conversely, the microvascular SNP response remained significantly higher in the Caucasian group, even after adjusting for skin resistance (P < 0.01). Diastolic blood pressure was inversely associated with the AUC of ACh (r = -0.4) and all SNP responses (r = -0.3 to -0.6). Skin resistance was inversely associated with AUC and maximum absolute ACh response (r = -0.59 and -0.64, respectively) and all SNP responses (r = -0.37 to -0.79). Ethnic differences in endothelium-independent microvascular function may contribute to ethnic disparities in cardiovascular disease. Moreover, skin resistance plays a significant role in the interpretation of the microvascular response to outcomes of iontophoresis in a multiethnic group.
Citation:
Exp Physiol. 2014 Jul;99(7):985-94.
Publisher:
Wiley
Journal:
Experimental physiology
Issue Date:
1-Jul-2014
URI:
http://hdl.handle.net/11287/593850
DOI:
10.1113/expphysiol.2014.078519
PubMed ID:
24803528
Additional Links:
http://dx.doi.org/10.1113/expphysiol.2014.078519
Type:
Journal Article; Research Support, Non-U.S. Gov't
Language:
eng
ISSN:
1469-445X
Appears in Collections:
2014 RD&E publications; Diabetes/Endocrine Services; Cardiology; Honorary contracts publications

Full metadata record

DC FieldValue Language
dc.contributor.authorPienaar, P. R.en
dc.contributor.authorMicklesfield, L. K.en
dc.contributor.authorGill, J. M.en
dc.contributor.authorShore, Angelaen
dc.contributor.authorGooding, K. M.en
dc.contributor.authorLevitt, N. S.en
dc.contributor.authorLambert, E. V.en
dc.date.accessioned2016-01-19T12:35:44Zen
dc.date.available2016-01-19T12:35:44Zen
dc.date.issued2014-07-01en
dc.identifier.citationExp Physiol. 2014 Jul;99(7):985-94.en
dc.identifier.issn1469-445Xen
dc.identifier.pmid24803528en
dc.identifier.doi10.1113/expphysiol.2014.078519en
dc.identifier.urihttp://hdl.handle.net/11287/593850en
dc.description.abstractMicrovascular dysfunction precedes the clinical manifestations of cardiovascular disease. Given the ethnic disparities in cardiovascular disease, we aimed to investigate ethnic differences in microvascular endothelial function in a group of young (18-33 years old), apparently healthy individuals (n = 33, nine Black African, 12 mixed ancestry and 12 Caucasian). Microvascular endothelium-dependent and -independent function was assessed by laser Doppler imagery and iontophoresis of ACh and sodium nitroprusside (SNP), respectively, adjusting for skin resistance. Microvascular reactivity was expressed as maximum absolute perfusion, percentage change from baseline and area under the curve (AUC). Skin resistance was significantly lower in the Caucasian group in response to ACh (Caucasian, mean 0.16 +/- 0.03 Omega versus Black, 0.21 +/- 0.04 Omega and mixed ancestry, 0.20 +/- 0.02 Omega, P < 0.01) and SNP (Caucasian, 0.08 +/- 0.01 Omega versus Black, 0.11 +/- 0.02 Omega and mixed ancestry, 0.12 +/- 0.01 Omega, P < 0.01). Microvascular function in response to ACh was significantly higher in the Caucasian group compared with the other two groups; however, after adjusting for skin resistance these differences were no longer significant. Conversely, the microvascular SNP response remained significantly higher in the Caucasian group, even after adjusting for skin resistance (P < 0.01). Diastolic blood pressure was inversely associated with the AUC of ACh (r = -0.4) and all SNP responses (r = -0.3 to -0.6). Skin resistance was inversely associated with AUC and maximum absolute ACh response (r = -0.59 and -0.64, respectively) and all SNP responses (r = -0.37 to -0.79). Ethnic differences in endothelium-independent microvascular function may contribute to ethnic disparities in cardiovascular disease. Moreover, skin resistance plays a significant role in the interpretation of the microvascular response to outcomes of iontophoresis in a multiethnic group.en
dc.language.isoengen
dc.publisherWileyen
dc.relation.urlhttp://dx.doi.org/10.1113/expphysiol.2014.078519en
dc.titleEthnic differences in microvascular function in apparently healthy South African men and womenen
dc.typeJournal Articleen
dc.typeResearch Support, Non-U.S. Gov'ten
dc.identifier.journalExperimental physiologyen

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