Efficacy of therapeutic fasting and plant-based diet in patients with rheumatoid arthritis (NutriFast): study protocol for a randomised controlled clinical trial

Abstract

BackgroundPrevious studies have shown beneficial effects of therapeutic fasting and plant-based dietary interventions on disease activity in patients with rheumatoid arthritis (RA) for a duration of up to 1 year. To date, the effects of such interventions on the gut microbiome and on modern diagnostic markers in patients with RA have not been studied. This trial aims to investigate the clinical effects of therapeutic fasting and a plant-based diet in patients with RA, additionally considering current immunological diagnostic tools and microbiome analyses.Methods/designThis trial is an open-label, single-centre, randomised, controlled, parallel-group clinical trial. We will randomly assign 84 patients with RA under a stable standard therapy to either (1) therapeutic fasting followed by a plant-based dietary intervention or (2) to a conventional nutritional counselling focusing on an anti-inflammatory dietary pattern according to the recommendations of the Deutsche Gesellschaft für Ernährung (German society for nutrition). Primary outcome parameter is the group difference from baseline to 12 weeks on the Health Assessment Questionnaire (HAQ). Other secondary outcomes include established clinical criteria for disease activity and treatment response in RA (Disease Activity Score 28, Simple Disease Activity Index, ACR-Response Criteria), changes in self-reported health and physical functional ability, mood, stress, quality of life, dietary behaviour via 3-day food records and a modified Food Frequency Questionnaire, body composition, changes in the gut microbiome, metabolomics and cytometric parameters. Outcomes will be assessed at baseline and day 7, after 6 weeks, 12 weeks and after 6 months.Ethics and disseminationEthical approval to process and analyse data, and to publish the results was obtained through the institutional review board of Charité-Universitätsmedizin Berlin. Results of this trial will be disseminated through peer-reviewed publications and scientific presentations.Trial registration numberNCT03856190.

To eat or not to eat—an exploratory randomized controlled trial on fasting and plant-based diet in rheumatoid arthritis (NutriFast-Study)

“…NutriFast was an open label, monocentric, randomized, controlled, parallel-group, explorative clinical trial. We registered the trial with ClinicalTrials.gov (NCT03856190) and published the study protocol in 2021 ( 33 ). The study was approved by the local ethics committee (EA 4/005/17) and conducted in accordance with the standards set out in the Declaration of Helsinki.…”

“…Eligibility criteria targeted patients on stable medication healthy enough to participate in an outpatient fasting program. Key exclusion criteria were arthritis other than RA, underweight, previous eating disorders, severe comorbidities, a strict PBD and/or fasting within the last 6 months or changes in therapy with DMARDs in the last 8 weeks before enrolment ( 33 ).…”

“…The dietary interventions were delivered as an intensive group-based behavioral intervention in an outpatient setting and have been described elsewhere ( 33 ). In brief, the intervention consisted of a 7-day fast with a daily energy intake of 300–350 kcal/day through vegetable juices and vegetable broth.…”

Post Hoc Analysis of a Randomized Controlled Trial on Fasting and Plant-Based Diet in Rheumatoid Arthritis (NutriFast): Nutritional Supply and Impact on Dietary Behavior

“…Between March 2019 and November 2020, we enrolled and randomized participants with RA on stable medication who were healthy enough to participate in an outpatient fasting program. Key exclusion criteria included previous eating disorders, underweight status, a strict plant-based diet and/or fasting within the last six months, as well as changes in therapy with DMARDs in the last 8 weeks before enrolment [ 18 ].…”

“…Participants were assigned to one of two treatment arms in a 1:1 ratio, which have been extensively described elsewhere [ 18 ]. In summary, the interventional study arm consisted of a 7-day fast followed by a whole-food plant-based diet (PBD) for 11 weeks.…”