Oral potassium (K+) administered as K+ enriched diet combined with a specially prepared K+ rich food based supplement reduces pain in Rheumatoid Arthritis (RA)
Authors: Kianifard Toktam M , Saluja Manjit Saluja , Venugopalan Anuuradha , Chopra Arvind 
Published: November 2023

RA is a life long painful disease complicated with joint disability, reduced quality of life and longevity. Drug therapy is potentially toxic. Dietary intervention remains controversial. Potassium (K +) is critical to pain neurophysiology. Voltage gated K+ ion channels are downregulated in chronic pain and may develop autoantibodies (Tsantoulas. Trends Neurosci 2014; 37:146 ). Body K+ status may be low in RA (NHANES III, USA). We showed low dietary K+ in Indian (Asian) patients (European League Association Rheumatology meeting 2014). We decided to evaluate the role of K+ to reduce pain in RA.

Methods

172 consenting patients with painful (>4 cms active pain visual analogue scale) chronic RA were enrolled into a randomized three arm study of 16 week duration as per protocol post ethic clearance. Patients in Arms A and B received structured dietary advice to increase K+ intake. A K+ enriched supplement was further provided to Arm B; Arm C continued routine diet (active control). All arms continued standard of care drug therapy and monitored analgesic rescue. The daily K+ intake was 3.5–4 gm in Arm A and 7.5–8 gm in Arm B. Standard efficacy/safety measures and diet intake were evaluated every month. Compliance checks included serum and urinary K+ assay and personal interviews. We followed the recommendations of the National Institute of Nutrition, Hyderabad, India (www.ninindia.org). The study (80% power, significant p <0.05) was analysed using SPSS. Arms were matched for several measures and withdrawals (A:8.8%; B:12.1%; C: 8.8%). On view of a low drop out, results of completer analysis are presented (ANOVA).

Results

Patients improved in each arm. On comparison, reduction in pain VAS was significant in Arm B (p=0.03). Similar results were shown for several other pain and efficacy measures that included disease activity clinical and quality of life (SF 36). On combining data and ensuring diet compliance (mean diet K+.3 gm daily), dietary K arms showed superior improvement‐patient global assess (p=0.04), Health Assessment Questionnaire (p=0.03) and SF36 physical score (p=0.03), painful joint counts (p=0.08), mean pain VAS (p=0.06); reduced systolic BP and increased serum cortisol (AM). Only mild adverse events were reported. Results of possible effect of high protein diet, night shade vegetables, Ayurveda (Indian medicine system) diet preferences on pain will be presented. Diet based studies have several challenges and limitations as was the current experience.

Conclusion

This first time pragmatic study of active painful RA in Indian (Asian) patients showed a clinically important pain reduction by diet based K+ augmentation over and above the standard care in rheumatology practice. The holistic advantage of using wholesome diet cannot be excluded. Other possible benefits included better disease control, lesser analgesic requirement, improved BP (cardiovascular) status and endogenous serum cortisol. Overall, this seemed to be a gentle and useful adjunct therapy in the management of RA.

Support or Funding Information

Arthritis Research Care Foundation‐Centre for Rheumatic Diseases