Abstract
Background: Diabetes is associated with sub-optimal vascular function. Current evidence suggested purified anthocyanins (ACNs) could improve cardio-metabolic health, but the dose-response effects on arterial stiffness have not been verified. Objectives: To assess the dose-responsiveness of purified ACNs on vascular stiffness and cardiovascular risk among Chinese middle-aged and elderly patients with either prediabetes or early diabetes. Methods: This was a secondary analysis based on a 12-week double-blind, randomized and placebo-controlled trial. Eligible participants were randomly assigned to placebo, 160, 320 and 640 mg/d ACNs groups (n = 46/group). Information on dietary intakes and lifestyle habits and blood samples were collected at baseline and at week 12. Arterial stiffness and vascular function were measured by brachial-ankle pulse wave velocity (baPWV), ankle-brachial index (ABI) and four-limb blood pressures. Composite cardiovascular indices were estimated based on lipids and anthropometric data. Results: Total 184 eligible participants were recruited and 19 withdrew during the intervention. Baseline characteristics were generally comparable among groups. No significant effects or dose-response relationships were observed by ACNs supplementation on arterial stiffness and cardiovascular risk factors. Conclusions: The 12-week randomized controlled trial among Chinese middle-aged and elderly adults with dysglycemia showed multiple dosages of anthocyanins had no significant impacts on arterial stiffness and cardiovascular risk.