Low-grade inflammation and metabolic syndrome are seen in many chronic diseases, including rheumatoid arthritis (RA) and osteoarthritis (OA). Lifestyle interventions which combine different non-pharmacological therapies have shown synergizing effects in improving outcomes in patients with other chronic diseases or increased risk thereof, especially cardiovascular disease. For RA and metabolic syndrome-associated OA (MSOA), whole food plant-based diets (WFPDs) have shown promising results. A WFPD, however, had not yet been combined with other lifestyle interventions for RA and OA patients. In this protocol paper, we therefore present Plants for Joints, a multidisciplinary lifestyle program, based on a WFPD, exercise, and stress management. The objective is to study the effect of this program on disease activity in patients with RA (randomized controlled trial [RCT] 1), on a risk score for developing RA in patients with anti-citrullinated protein antibody (ACPA) positive arthralgia (RCT 2) and on pain, stiffness, and function in patients with MSOA (RCT 3), all in comparison with usual care.We designed three 16-week observer-blind RCTs with a waiting-list control group for patients with RA with low to moderate disease activity (2.6 ≤ Disease Activity Score [DAS28] ≤ 5.1, RCT 1, n = 80), for patients at risk for RA, defined by ACPA-positive arthralgia (RCT 2, n = 16) and for patients with metabolic syndrome and OA in the knee and/or hip (RCT 3, n = 80). After personal counseling on diet and exercise, participants join 10 group meetings with 6-12 other patients to receive theoretical and practical training on a WFPD, exercise, and stress management, while medication remains unchanged. The waiting-list control group receives usual care, while entering the program after the RCT. Primary outcomes are: difference in mean change between intervention and control groups within 16 weeks for the DAS28 in RA patients (RCT 1), the RA-risk score for ACPA positive arthralgia patients (RCT 2), and the Western Ontario and McMaster Universities Arthritis Index (WOMAC) score for MSOA patients (RCT 3). Continued adherence to the lifestyle program is measured in a two-year observational extension study.
ObjectiveTo determine the effect of a multidisciplinary lifestyle program in patients with RA with low–moderate disease activity.MethodsIn the ‘Plants for Joints’ (PFJ) parallel-arm, assessor-blind randomized controlled trial, patients with RA and 28-joint DAS (DAS28) ≥2.6 and ≤5.1 were randomized to the PFJ or control group. The PFJ group followed a 16-week lifestyle program based on a whole-food plant-based diet, physical activity and stress management. The control group received usual care. Medication was kept stable 3 months before and during the trial whenever possible. We hypothesized that PFJ would lower disease activity (DAS28). Secondary outcomes included anthropometric, metabolic and patient-reported measures. An intention-to-treat analysis with a linear mixed model adjusted for baseline values was used to analyse between-group differences.ResultsOf the 83 people randomized, 77 completed the study. Participants were 92% female with mean (S.D.) age of 55 (12) years, BMI of 26 (4) kg/m2 and mean DAS28 of 3.8 (0.7). After 16 weeks the PFJ group had a mean 0.9-point greater improvement of DAS28 vs the control group (95% CI 0.4, 1.3; P < 0.0001). The PFJ intervention led to greater decreases in body weight (difference –3.9 kg), fat mass (–2.8 kg), waist circumference (–3 cm), HbA1c (–1.3 mmol/mol) and low-density lipoprotein (–0.32 mmol/l), whereas patient-reported outcome measures, blood pressure, glucose and other lipids did not change.ConclusionThe 16-week PFJ multidisciplinary lifestyle program substantially decreased disease activity and improved metabolic status in people with RA with low–moderate disease activity.Trial RegistrationInternational Clinical Trials Registry Platform; https://www.who.int/clinical-trials-registry-platform; NL7800.
