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Vasculoprotective Effects of Dietary Cocoa Flavanols in Patients on Hemodialysis: A Double-Blind, Randomized, Placebo-Controlled Trial

Rassaf, T., Rammos, C., Hendgen-Cotta, U. B., Heiss, Christian, Kleophas, W., Dellanna, F., Floege, J., Hetzel, G. R. and Kelm, M. (2015) Vasculoprotective Effects of Dietary Cocoa Flavanols in Patients on Hemodialysis: A Double-Blind, Randomized, Placebo-Controlled Trial Clinical Journal of the American Society of Nephrology, 11 (1). pp. 108-118.

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Background and objectives: Hemodialysis (HD) per se entails vascular dysfunction in patients with ESRD. Endothelial dysfunction is a key step in atherosclerosis and is characterized by impaired flow–mediated dilation (FMD). Interventional studies have shown that cocoa flavanol (CF)–rich supplements improve vascular function. Aim of this study was to investigate the effect of flavanol–rich bioactive food ingredients on acute and chronic HD–induced vascular dysfunction in ESRD. Design, setting, participants, &amp; measurements: We conducted a randomized, double–blind, placebo–controlled trial from 2012 to 2013. Fifty-seven participants were enrolled, ingested CF-rich beverages (900 mg CF per study day), and were compared with those ingesting CF-free placebo. This included (1) a baseline cross–over acute study to determine safety and efficacy of CF and (2) a subsequent chronic parallel group study with a 30-day follow-up period to study effects of CF on HD–mediated vascular dysfunction entailing (3) an acute substudy during HD in flavanol-naive patients and (4) an acute on chronic study during HD. Primary and secondary outcome measures included changes in FMD and hemodynamics. Results: CF ingestion was well tolerated. Acute ingestion improved FMD by 53% (3.2±0.6% to 4.8±0.9% versus placebo, 3.2±0.7% to 3.3±0.8%; P<0.001), with no effects on BP or heart rate. A 30-day ingestion of CF led to an increase in baseline FMD by 18% (3.4±0.9% to 3.9±0.8% versus placebo, 3.5±0.7% to 3.5±0.7%; P<0.001), with reduced diastolic BP (73±12 to 69±11 mmHg versus placebo, 70±11 to 73±13 mmHg; P=0.03) and increased heart rate (70±12 to 74±13 bpm versus placebo, 75±15 to 74±13 bpm; P=0.01). No effects were observed for placebo. Acute ingestion of CF during HD alleviated HD–induced vascular dysfunction (3.4±0.9% to 2.7±0.6% versus placebo, 3.5±0.7% to 2.0±0.6%; P<0.001). This effect was sustained throughout the study (acute on chronic, 3.9±0.9% to 3.0±0.7% versus placebo, 3.5±0.7% to 2.2±0.6; P=0.01). Conclusions: Dietary CF ingestion mitigates acute HD–induced and chronic endothelial dysfunction in patients with ESRD and thus, improves vascular function in this high-risk population. Larger clinical trials are warranted to test whether this translates into an improved cardiovascular prognosis in patients with ESRD.

Item Type: Article
Divisions : Faculty of Health and Medical Sciences > School of Biosciences and Medicine
Authors :
Rassaf, T.
Rammos, C.
Hendgen-Cotta, U. B.
Kleophas, W.
Dellanna, F.
Floege, J.
Hetzel, G. R.
Kelm, M.
Date : December 2015
DOI : 10.2215/​CJN.05560515
Uncontrolled Keywords : cocoa-flavanols; endothelial function; hemodialysis; vascular functions; nutrition; blood pressure; double-blind method; heart rate; hemodynamics; humans; kidney failure, chronic
Depositing User : Melanie Hughes
Date Deposited : 16 Aug 2018 10:48
Last Modified : 16 Aug 2018 10:48

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