A Pilot Study of Potassium Supplementation for Adult Patients With Rheumatoid Arthritis
Condition: Rheumatoid Arthritis
MeSH terms: Arthritis; Arthritis, Rheumatoid
Study type: Interventional
Phase: Phase 1

Summary: 
      Rheumatoid arthritis is the paradigmatic immune-mediated inflammatory arthropathy. With
      respect to rheumatoid arthritis (RA), patients have been described as having inappropriately
      low spontaneous and stimulated cortisol secretion levels. Serum cortisol levels are decreased
      in RA patients who are taking prednisolone. Also, in patients RA, of longer duration,
      glucocorticoid receptor (GR) down-regulation has been reported without any change in cortisol
      levels. There is a reduced capacity for local reactivation of cortisone to cortisol in RA
      synovial cells. It is noteworthy that since synthetic glucocorticoids also use same
      reactivation shuttle (the cortisol-cortisone shuttle), the results also apply to therapeutic
      glucocorticoids.

      Glucocorticoids are widely used to treat chronic inflammatory conditions including rheumatoid
      arthritis. Prednisolone has a greater effect than non-steroidal, anti-inflammatory drugs on
      joint tenderness and pain, whereas the difference in grip strength was not significant. There
      are no qualitative differences between the effects of endogenous cortisol and exogenously
      applied synthetic glucocorticoids, since all effects are transmitted via the same receptor.
      Cortisol, on the other hand, plays a major role in normal potassium homeostasis.

      Recent studies have highlighted a role for diet, with suggestions that diets high in
      caffeine, low in antioxidants and high in red meat may contribute to an increased risk for
      the development of rheumatoid arthritis. Higher intakes of complex carbohydrates, dietary
      fiber, magnesium, folic acid, vitamin C and E, carotenoids and other phytochemicals have been
      shown to offer distinct advantages compared to diets containing meat and other foods of
      animal origin. The relation of a potassium deficiency to RA is much less well documented. The
      first person to definitively link potassium with arthritis was DeCoti Marsh. LaCelle, Morgan
      & Atwater found that the cells of 50 arthritic patients were 30 to 50% lower than healthy
      people.

      Our current clinical trial (clinical trial no NCT00399282) shows that most of patients with
      RA do not have enough potassium intake. This condition may contribute to a subclinical lower
      serum cortisol, although there is possibility that cortisol serum levels might be unchanged
      due to a sufficient "cortisol homeostasis" and "potassium homeostasis".
    

Detailed description: 
      This study examines the hypothesis if patients with rheumatoid arthritis evaluate, or rate,
      symptom improvements after potassium supplementation (as KCl).

      Participants will undergo the following tests and procedures:

      Medical history and physical examination. Measurements of weight and height. Blood sample
      collections for clinical and research purposes. Quality of life questionnaires.

      We therefore examined the hypothesis that examines effect of an orally administrated grape
      juice enriched (GJE) with 6000 mg potassium (as KCl) compared with that of a placebo grape
      juice (PGJ) on serum indices (cortisol, ACTH, aldosterone, creatinine, pH, Na, K), urinalysis
      (urea, uric acid, K, Na, creatinine, pH), GFR corrected by body surface area, ESR, CRP, RF,
      pain, quality of life, and disease activity in a case-controlled double-blind protocol in
      patients with RA with an established low dietary potassium intake to further investigate
      endogenous cortisol secretion and consequent possible relief.

      Clinical (like Disease Activity, Pain) variables, along with the Quality of Life, and
      Biochemical Indices will be compared in two groups of patients after 28 days of oral GJE and
      PJE administration.
    

Intervention name(s): Potassium supplement
Intervention type(s): Dietary Supplement
Intervention description(s): Patients were randomly allocated to receive either an EGJ containing 234.5 mmol microcrystalline KCl a total of 6000 mg of K in 2 EGJ, but split into 2 intakes daily) or PGJ for 28 days.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Supportive Care
Keywords: Potassium supplement; Rheumatoid Arthritis; Pain; Disease Activity