Acute effects of beetroot juice ingestion on blood flow and blood pressure in diabetic patients with early-stage peripheral artery disease

Abstract

The objective of the study was to determine the acute effects of beetroot juice ingestion on blood flow and blood pressure in diabetic patients with early-stage peripheral arterial disease compared to non-diabetic controls. In this quasi-experimental cohort study of 35 Black-African diabetic patients and 36 non-diabetic controls, peak systolic velocity (PSV), systolic blood pressure (SBP) and diastolic blood pressure (DBP) were utilised to assess blood flow in the popliteal arteries (PA) basally, 90 minutes, 150 minutes, and 210 minutes-post-ingestion of beetroot juice both between and within groups. A two-way analysis of variance with Benferroni post-hoc analysis were performed to compare the two groups across 4-time points after the intake of beetroot juice. One sample and two-sample t-tests with Cohen’s d effects sizes were performed to determine whether any changes in dependant variables were significant and meaningful within and between groups. Within groups, PSV, SBP and DBP reduced significantly and meaningfully during baseline to 90 minutes and 150 minutes-210 minutes’ time points (P ≤0.02; d ≤1.70). However, no significant or meaningful change (P ≤0.9; d ≤0.29) occurred in PSV, SBP and DBP during the 90 minutes to 150 minutes’ time point. Between groups, PSV and DBP were significantly and meaningfully higher (P ≤0.04; d ≤1.95) in diabetic patients at baseline. At 90 minutes and 150 minutes PSV remained higher in diabetic patients (P ≤0.04; d ≤1.30) unlike SBP (P ≤0.8; d ≤0.34). At 210 minutes, PSV and SBP did not change significantly or meaningfully (P ≤0.59; d ≤0.18) between groups while DBP showed no significant or meaningful difference (P ≤0.7; d ≤0.33) between the groups at all the time points. The combined group effects were significant for PSV (diff ≤ 20.0 cm/s; P <0.0001) across all the time points except between 90 minutes to 150 minutes (diff = 0.4cm/s; P = 1.0) The combined group effects were significant for SBP (diff ≤ 22.01mmHg; P <0.0001) amongst all the time points except 90 minutes to 150 minutes time point (diff = 1.2 mmHg; P = 1.00) and finally the combined group effects for DBP were significant and meaningful (diff ≤13.4 mmHg; P <0.0001) amongst all the time points except 90 minutes to 150 minutes (diff = 1.34 mmHg; P = 1.00) after beetroot juice ingestions. The acute effects of beetroot juice on the blood flow of the popliteal artery were reflected as lowered PSV, SBP and DBP during the 150-210 minutes’ time point in both groups.