Toggle Main Menu Toggle Search

Open Access padlockePrints

Ageing modifies the effects of beetroot juice supplementation on 24-hour blood pressure variability: An individual participant meta-analysis

Lookup NU author(s): Dr Mario Siervo, Dr Jose Lara-Gallegos, Ammar Ashor, Dr Kirsten BrandtORCiD, Othman Qadir, Professor John Mathers

Downloads

Full text for this publication is not currently held within this repository. Alternative links are provided below where available.


Abstract

© 2015 Elsevier Inc. All rights reserved. Objectives: Abnormal circadian oscillations of blood pressure (BP) and nocturnal-diurnal BP differences (i.e., dipping) increase cardiovascular risk. Whether inorganic nitrate supplementation influences 24-hr BP variability is currently unknown. We studied the effects of high-nitrate beetroot juice supplementation on BP variability measured by 24-hr ambulatory BP monitoring (24-hr ABPM) in older subjects. Methods: Data from four independent randomised clinical trials were collated. Eighty-five older participants (age range: 55-76 years) were included in the final database. Two trials had an open-label, parallel design and two trials had a cross-over, double-blind design. Participants were randomised to either beetroot juice or placebo. Changes in 24-hr ABPM (daily, diurnal, nocturnal), variability (weighted-SDs), night-dipping, morning surge for systolic and diastolic BP were measured. Meta-analysis was conducted to obtain pooled estimates of the effect size for each BP outcome. Sub-group analyses were conducted to evaluate the influence of age, BMI, gender, BP status and changes in nitrite concentrations on the effect size. Results: The pooled effect of beetroot juice on all BP outcomes was not significant. Beetroot juice ingestion determined a significant decrease in nocturnal systolic BP variability in subjects aged less than 65y (2.8mmHg, -4.5 -1.0, p=0.002) compared to the older group (≥65y; 1.0mmHg, -2.2 4.2, p=0.54). A greater change in NO<inf>2</inf><sup>-</sup> concentrations after beetroot supplementation was associated with significant differences for nocturnal mean (-3.4mmHg, -0.6 -2.4, p=0.02) and variability (-0.8mmHg, -1.5 -0.06, p=0.03) of systolic BP. Conclusions: The vascular responsiveness to inorganic nitrate may be modified by mechanisms of vascular ageing influencing the reducing capacity to convert inorganic nitrate into nitrite and tissue-specific responses to dietary nitrate supplementation.


Publication metadata

Author(s): Siervo M, Lara J, Jajja A, Sutyarjoko A, Ashor AW, Brandt K, Qadir O, Mathers JC, Benjamin N, Winyard PG, Anning C, Shore A, Gilchrist M

Publication type: Article

Publication status: Published

Journal: Nitric Oxide

Year: 2015

Volume: 47

Pages: 97-105

Print publication date: 01/05/2015

Online publication date: 29/04/2015

Acceptance date: 25/04/2015

ISSN (print): 1089-8603

ISSN (electronic): 1089-8611

Publisher: Elsevier

URL: http://doi.org/10.1016/j.niox.2015.04.007

DOI: 10.1016/j.niox.2015.04.007


Altmetrics

Altmetrics provided by Altmetric


Share