Cardiovascular function

1. Vascular Reactivity.  Endothelial function as indexed by flow-mediated brachial artery dilatation (FMD).  Changes in brachial artery diameter during reactive hyperemia are measured by high-resolution ultrasound.  Pulse wave velocity and central aortic augmentation index are calculated using large artery applanation tonometry.



2. Impedance cardiography as measured by thoracic electrical impedance using 4 dual sensors on neck and chest.  Measures include cardiac output (CO), systemic vascular resistance (SVR), and thoracic fluid content (TFC).



3. Ambulatory blood pressure monitoring.  Twenty-four hour blood pressure values are obtained with use of programmable ambulatory blood pressure monitors.  

Andrade J, Er L, Ignaszewski A, Levin A. Exploration of Association of 1,25-OH2D3 with Augmentation Index, a Composite Measure of Arterial Stiffness. Clin J Am Soc Nephrol 2008. http://cjasn.asnjournals.org/cgi/rapidpdf/CJN.00900208v1.pdf

Sugden JA, Davies JI, Witham MD, Morris AD, Struthers AD. Vitamin D improves endothelial function in patients with Type 2 diabetes mellitus and low vitamin D levels. Diabet Med 2008;25:320-5. http://www3.interscience.wiley.com/cgi-bin/fulltext/119405111/PDFSTART

Li YC. Vitamin D regulation of the renin-angiotensin system. J Cell Biochem 2003;88:327-31. http://www3.interscience.wiley.com/cgi-bin/fulltext/99520608/PDFSTART

Wang TJ, Pencina MJ, Booth SL et al. Vitamin D Deficiency and Risk of Cardiovascular Disease. Circulation 2008;117:503-11. http://circ.ahajournals.org/cgi/reprint/117/4/503

Goff DC, Jr., Zaccaro DJ, Haffner SM, Saad MF. Insulin Sensitivity and the Risk of Incident Hypertension: Insights from the Insulin Resistance Atherosclerosis Study. Diabetes Care 2003;26:805-9. http://care.diabetesjournals.org/cgi/reprint/26/3/805

Jimenez MV, Estepa RM, Camacho RM, Estrada RC, Luna FG, Guitarte FB. Endothelial dysfunction is related to insulin resistance and inflammatory biomarker levels in obese prepubertal children. Eur J Endocrinol 2007;156:497-502.  http://eje-online.org/cgi/reprint/156/4/497

Lee S, Gungor N, Bacha F, Arslanian S. Insulin Resistance: Link to the components of the metabolic syndrome and biomarkers of endothelial dysfunction in youth. Diabetes Care 2007;30:2091-7.  http://care.diabetesjournals.org/cgi/reprint/30/8/2091

Suzuki M, Takamisawa I, Suzuki K et al. Close association of endothelial dysfunction with insulin resistance and carotid wall thickening in hypertension. Am J Hypertens 2004;17:228-32.  http://www.nature.com/ajh/journal/v17/n3/pdf/ajh200442a.pdf

Tousoulis D, Tsarpalis K, Cokkinos D, Stefanadis C. Effects of insulin resistance on endothelial function: possible mechanisms and clinical implications. Diabetes Obes Metab 2008;10:834-42.  http://www3.interscience.wiley.com/cgi-bin/fulltext/120125606/PDFSTART