Pilot Study of Nitrate-rich Beetroot Juice Supplementation in Patients With Idiopathic Pulmonary Fibrosis (IPF)

Summary

Idiopathic pulmonary fibrosis (IPF) is a type of scarring (fibrotic) lung disease. Reduced exercise capacity is a key symptom experienced by patients. In previous research the investigators identified that an interval-based exercise programme led to significant improvements in exercise capacity (Wallis et al Antioxidants. 2023).

An unexpected finding was that in patients with IPF, exercise led to a reduction in blood nitrite concentrations an observation the investigators did not see in non-affected individuals. Research has identified that nitrite concentrations are expected to increase after exercise and the size of this increase is related to an individual's exercise capacity. There is also evidence from healthy individuals and patients with chronic obstructive pulmonary disease (COPD) that nitrate supplementation (a source of nitrite) improves response to exercise training. However, in both these groups an exercise-induced fall in blood nitrite concentrations has not been observed. Hence our finding of an exercise-induced fall in blood nitrite levels in IPF patients suggest that they may be especially sensitive to supplementation with nitrate, commercially available as nitrate-rich beetroot juice (NRBJ).

This current study investigates this in a pilot placebo-controlled, double-blind, randomised, cross-over study of NRBJ on exercise capacity in IPF patients.

Aims In patients with IPF

* Quantify the effect of nitrate supplementation on exercise capacity
* Determine the effect of nitrate supplementation on blood markers of nitric oxide production/metabolism.
* Determine the effect of nitrate supplementation on forearm blood flow. Sample size: n=8 IPF patients, aged 18-85years and medical research breathlessness scale 1-3 Intervention: 3-days (two-times daily) NRBJ or nitrate-depleted placebo juice (both commercially available) with subsequent constant-load exercise test (Primary outcome). Following at least 1 week wash-out period participants will cross-over and repeat.

A cohort (n=8) of age, sex-matched controls without IPF will be enrolled for comparison of forearm blood flow and pre-exercise venous blood samples for biomarkers comparison only.

Number of sites: 1

Conditions

• Idiopathic Pulmonary Fibrosis
• Interstitial Lung Disease

Interventions

DIETARY_SUPPLEMENT

nitrate-rich beetroot juice (70ml with approx. 400 mg nitrate) twice a day for 3 days

commercially available beetroot juice dietary nitrate supplement

Sponsors & Collaborators

• NIHR Southampton Respiratory Biomedical Research Centre

  collaborator UNKNOWN

• Asthma, Allergy and Inflammation Research (AAIR) Charity

  collaborator UNKNOWN

• University Hospital Southampton NHS Foundation Trust

  lead OTHER

Principal Investigators

• Tim JM Wallis, MD, PhD · University Hospital Southampoton

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

TRIPLE

Model

CROSSOVER

Eligibility

Min Age

28 Years

Max Age

85 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2024-09-30

Primary Completion

2025-09-30

Completion

2026-09-30