COCOA

Among people with peripheral artery disease (PAD) age 55 and older, we will test the hypothesis that PAD participants randomized to cocoa flavanols will have greater improvement or less decline in six-minute walk distance at six-month follow-up, compared to those randomized to placebo. We will randomize 190 participants (32 in Minnesota) with PAD age 55 and older to one of two groups for six months: cocoa flavanols vs placebo. Our primary outcome is change in six-minute walk distance at six-month follow-up. Secondary outcomes are six-month change in maximal treadmill walking distance, Actigraph-measured physical activity, whole body oxygen consumption, measures of nitric oxide (brachial artery flow-mediated dilation (FMD)), calf muscle endothelial nitric oxide synthase (eNOS) and phosphorylated eNOS, calf muscle perfusion (measured by magnetic resonance imaging (MRI)) and calf muscle characteristics (measured by calf muscle biopsy). To achieve our specific aims, we will randomize 190 participants age 55 and older with PAD to one of two groups: cocoa flavanols vs placebo. Participants will be followed for seven months.