Prediction of future cardiovascular outcomes by flow-mediated vasodilatation of brachial artery: a meta-analysis
- 1.7k Downloads
We conducted a meta-analysis of observational studies which examined the association between flow-mediated dilatation (FMD) of brachial artery, a noninvasive measure of endothelial function, and future cardiovascular events.
Electronic databases were searched using a predefined search strategy. Data was independently abstracted on study characteristics, study quality, and outcomes by two reviewers. The multivariate relative risks, adjusted for confounding factors, were calculated from individual studies and then pooled using random-effects models. Statistical heterogeneity was evaluated using I2 statistics. Subgroup analyses and meta-regression analyses were conducted to assess the robustness of the meta-analysis. Publication bias was examined with funnel plot analysis and Egger’s test.
Four population-based cohort studies and ten convenience-cohort studies, involving 5,547 participants, were included in the meta-analysis. The pooled relative risks of cardiovascular events per 1% increase in brachial FMD, adjusted for confounding risk factors, was 0.87 (95% CI, 0.83- 0.91). The significant associations between brachial FMD and cardiovascular events were consistent among all subgroups evaluated, suggesting the robustness of the meta-analysis. However, the presence of heterogeneity in study quality, the remaining confounding factors, and publication bias in the available literature prevent a definitive evaluation of the additional predictive value of brachial FMD beyond traditional cardiovascular risk factors.
The meta-analysis of heterogeneous studies with moderate methodological quality suggested that impairment of brachial FMD is significantly associated with future cardiovascular events. Further prospective randomized trials are warranted to confirm the efficacy of the usage of brachial FMD in the management of cardiovascular diseases.
KeywordsEndothelium Imaging Meta-analysis Vasodilation
The authors’ responsibilities were as follows—YI: selected studies, extracted and analyzed the data, performed the statistical analyses, wrote the manuscript, and takes responsibility for data integrity and accuracy of data analysis; JAC: designed the present study, selected studies, extracted and analyzed the data, and contributed to the writing of the manuscript; SRB: supervised the present study, contributed to the data interpretation and writing of the manuscript. All authors agreed on the final version of the manuscript. All authors have access to the data and a role in writing the manuscript.
- 5.Medline cohort study filter (2008) Search filters; 2008. Filter designed by knowledge information specialists from British Medical Journal. Accessed at www.clinicalevidence.com/ceweb/about/search_filters.jsp, on November 11, 2008
- 7.Higgins JPT, Green S (eds) (2006) Cochrane handbook for systematic reviews of interventions 4.2.6 [updated September 2006]. In: The Cochrane Library, Issue 4, 2006. Wiley, ChichesterGoogle Scholar
- 23.Karatzis EN, Ikonomidis I, Vamvakou GD, Papaioannou TG, Protogerou AD, Andreadou I, Voidonikola PT, Karatzi KN, Papamichael CM, Lekakis JP (2006) Long-term prognostic role of flow-mediated dilatation of the brachial artery after acute coronary syndromes without ST elevation. Am J Cardiol 98:1424–1428CrossRefPubMedGoogle Scholar
- 27.Shechter M, Issachar A, Marai I, Koren-Morag N, Freinark D, Shahar Y, Shechter A, Feinberg MS (2009) Long-term association of brachial artery flow-mediated vasodilation and cardiovascular events in middle-aged subjects with no apparent heart disease. Int J Cardiol 134:52–58CrossRefPubMedGoogle Scholar
- 28.Muiesan ML, Salvetti M, Paini A, Monteduro C, Galbassini G, Poisa P, Porteri E, Agabiti-Rosei C, Paderno V, Belotti E, Rizzoni D, Castellano M, Agabiti-Rosei E (2008) Prognostic role of flow-mediated dilatation of the brachial artery in hypertensive patients. J Hypertens 26:1612–1618CrossRefPubMedGoogle Scholar
- 30.Hamburg NM, Larson MG, Vita JA, Vasan RS, Keyes MJ, Widlansky ME, Fox CS, Mitchell GF, Levy D, Meigs JB, Benjamin EJ (2008) Metabolic syndrome, insulin resistance, and brachial artery vasodilator function in Framingham Offspring participants without clinical evidence of cardiovascular disease. Am J Cardiol 101:82–88CrossRefPubMedGoogle Scholar