Abstract 3277: Sustained Benefits in Vascular Function through Flavanol-Containing Cocoa in Medicated Diabetic Patients: A Double-Masked, Randomized, Controlled Trial

Abstract

Purpose Epidemiological investigations revealed an inverse correlation between the dietary intake of flavanols, the mortality of cardiovascular disease, and the incidence of diabetes. Controlled trials evaluating longer-term effects of flavanol-containing cocoa on endothelial function in diabetic patients are missing. This study was designed to test feasibility and efficacy of a dietary intervention based on daily intake of flavanol-containing cocoa for improving vascular function of medicated diabetic patients. Methods In a feasibility study with 10 diabetic patients, we assessed vascular function as flow-mediated dilation (FMD) of the brachial artery, plasma levels of flavanol metabolites, and tolerability following an acute, single-dose ingestion of cocoa, containing increasing concentrations of flavanols (75,371,963mg). In a subsequent efficacy study, changes in vascular function in 41 medicated diabetics were assessed following a 30-day, thrice-daily dietary intervention with either flavanol-rich cocoa (321mg flavanols per dose) or a nutrient-matched control (25mg flavanols per dose). Both studies were undertaken in a randomized, double-masked fashion. Results A single ingestion of flavanol-containing cocoa was dose-dependently associated with significant acute increases in circulating flavanols and FMD (at 2h: from 3.7±0.2% to 5.5±0.4%, p<0.001). A 30-day, thrice-daily consumption of flavanol-containing cocoa increased baseline FMD by 30% (p<0.0001), while acute increases of FMD upon ingestion of flavanol-containing cocoa continued to be manifest throughout the study. Treatment was well tolerated without evidence of tachyphylaxia. Endothelium-independent responses, blood pressure, heart rate, and glycemic control were unaffected. Conclusions Our study clearly establishes improvements of endothelial function after regular consumption of flavanol-containing cocoa in patients with type 2 diabetes, highlighting the potential of flavanol-containing diets, and underscoring the potential health care benefit for reducing the risk of cardiovascular events in diabetic patients.