Feasibility Study: Plant Based Diet to Patients With Rheumatoid Arthritis

In this feasibility study, our primary goal is to assess the practicality of implementing a plant-based food diet intervention for individuals with rheumatoid arthritis (RA). The intervention consists of three key components: 1) Educational materials (videos), 2) Participation in a cooking workshop introducing plant-based meals, complete with recipes, and 3) Daily delivery of plant-based dinner meals over a four-week period. This comprehensive investigation covers the testing of recruitment procedures, randomization, intervention elements, outcome assessments, and participant retention.

Adopting a daily plant-based diet involves introducing several new plant-based foods and making adjustments to the existing diets of patients with RA. Consequently, the feasibility study will also aim to explore the acceptability of the intervention and whether a full-scale RCT is practically possible.

Rheumatoid arthritis (RA) is a common chronic autoimmune disease requiring lifelong pharmacological treatment and causing significant burden to the patient and society. Evidence has suggested that it is important that patients take an active role in their self-management to improve their overall health and quality of life. Effective self-management strategies often involve changes in lifestyle. We have previously conducted a lifestyle intervention study to reduce sedentary behavior and increase physical activity in 150 patients with RA. An individually tailored intervention motivating patients to self-manage their arthritis by reducing sedentary behavior and replacing it with light-intensity physical activity reduced disease activity, e.g., levels of pain and fatigue. Nutrition may be another important part of self-management strategies in patients with RA. Emerging evidence suggests that an anti-inflammatory diet may reduce disease activity and improve quality of life among patients with RA.3 Compared to a diet including animal foods, a Plant-Based Diet (PBD) is believed to include less of the pro-inflammatory, and more of the anti-inflammatory, ingredients, and thus may have the potential to reduce disease activity in patients with RA.

Our overall and long-term aim is to test and evaluate the effect of a PBD intervention on disease activity in patients with RA in a later randomized controlled trial (RCT). As a first step towards this, we wish to investigate strengths and limitations of the planned intervention, which introduces a PBD to patients with RA.

Thus, in a feasibility study, we aim to investigate the feasibility of the intervention, including recruitment procedures, randomization, intervention elements, outcome assessments and retention. Following a daily PBD will involve inclusion of several new plant-based foods and changes in earlier diets for patients with RA. As such, the feasibility study will also aim to investigate acceptability of the intervention, including how people with RA respond to the intervention elements and how a PBD affect their daily lives (e.g. how easy is it to prepare plant-based foods, how desirable is it to eat, and how does it affect digestion). Ultimately, the findings from this feasibility study will provide crucial insights into whether a full-scale randomized controlled trial (RCT), designed to evaluate the effects of a 100% plant-based diet on patients with RA, is a feasible and realistic undertaking.

Eligibility Criteria:
Inclusion Criteria:

* Disease Activity Score with 28 Joint Counts (DAS28) between 2.0-3.2
* A rheumatoid arthritis diagnosis of minimum 1 year
* Under stable pharmaceutical treatment for at least 4 months and with no planned change in treatment within 8 weeks

Exclusion Criteria:

* Daily smokers
* Diabetes Mellitus
* Pregnancy / planned pregnancy
* Lactation
* Prednisolone treatment
* DAS28 below 2.0 and above 3.2
* Current dietary habits resembling intervention diet (e.g., 100% plant based diets)
* Participation in other intervention studies or clinical trials via the rheumatology outpatient clinic that will affect their adherence to plant based diets
* Not able to eat ad libitum meals because of e.g., allergy
* Unable to understand the informed consent and study procedures
* Alcohol and/or drug abuse