NCT00461448

Brief 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".

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
36

participants targeted

Target at P50-P75 for phase_1 rheumatoid-arthritis

Timeline
Completed

Started Feb 2007

Shorter than P25 for phase_1 rheumatoid-arthritis

Geographic Reach
1 country

2 active sites

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Start

First participant enrolled

February 1, 2007

Completed
2 months until next milestone

Primary Completion

Last participant's last visit for primary outcome

April 1, 2007

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

April 1, 2007

Completed
16 days until next milestone

First Submitted

Initial submission to the registry

April 17, 2007

Completed
1 day until next milestone

First Posted

Study publicly available on registry

April 18, 2007

Completed
Last Updated

February 6, 2009

Status Verified

February 1, 2009

Enrollment Period

2 months

First QC Date

April 17, 2007

Last Update Submit

February 4, 2009

Conditions

Keywords

Potassium supplementRheumatoid ArthritisPainDisease Activity

Outcome Measures

Primary Outcomes (10)

  • Patient's dietary and supplement potassium intake (combined technique: food frequency questionnaire, 24 hour food-recall, food record), serum potassium

    within the 28 days (plus or minus 2 days)

  • Disease Activity Score (DAS28, 28-joint count) at d 0, 28

    within the first 28 days (plus or minus 2 days)

  • Patient's global assessment of disease activity (0 to 10 cm visual analog scale: 0, symptom free; 10, very severe) at d 0, 28

    within the first 28 days (plus or minus 2 days)

  • Patient's visual analogue scale (VAS) for pain at d 0, 28

    within the first 28 days (plus or minus 2 days)

  • Duration of morning stiffness (in minutes) at d 0, 28

    within the first 28 days (plus or minus 2 days)

  • Joint pain intensity, on a visual analogue scale (VAS) for pain (0 = no pain to 100mm =severe pain) at d 0, 28

    within the first 28 days (plus or minus 2 days)

  • Onset of fatigue (in minutes) after walking at d 0, 28

    within the first 28 days (plus or minus 2 days)

  • Ritchie's articular index for pain joints at d 0, 28

    within the first 28 days (plus or minus 2 days)

  • Right and left grip strength (in mmHg) measured with a sphygmomanometer cuff inflated to 20 mmHg at d 0, 28

    within the first 28 days (plus or minus 2 days)

  • Classification of functional status in RA according to revised criteria of the American College of Rheumatology at Patient's global assessment of disease activity (0 to 10 cm visual analog scale: 0, symptom free; 10, very severe) at d 0, 28

    within the first 28 days (plus or minus 2 days)

Secondary Outcomes (1)

  • Serum cortisol, NA, K, ACTH, aldosterone, creatinine, urea, uric acid, pH; urinalysis (urea, uric acid, Na, K, pH, creatinine), CRP, RF, and ESR at d 0, 28

    within the first 28 days (plus or minus 2 days)

Study Arms (2)

1 Potassium supplement

ACTIVE COMPARATOR

Patients received an Enriched Grape Juice containing 234.5 mmol microcrystalline KCl (a total of 6000 mg of K in 2 EGJ, but split into 2 intakes daily)

Dietary Supplement: Potassium supplement

2 Grape Juice

PLACEBO COMPARATOR

Patients received same amount of grape juice for 28 days.

Dietary Supplement: Potassium supplement

Interventions

Potassium supplementDIETARY_SUPPLEMENT

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.

1 Potassium supplement2 Grape Juice

Eligibility Criteria

Age18 Years - 60 Years
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64)

You may qualify if:

  • Age 18 years or older
  • Diagnosis of RA, as defined by fulfilling at least four of seven American College of Rheumatology (ACR) criteria
  • Onset of arthritis after the age of 16 years
  • Positive for rheumatoid factor (RF)
  • Active RA, as defined by at least four swollen joints, at least four tender joints, and either an erythrocyte sedimentation rate (ESR) of greater than 30 mm/hr OR C-reactive protein level greater than 1.0 mg/dl (normal less than 0.4)
  • Willing to follow the study protocol
  • Willing to intake PGJ or EGJ
  • On a salt-restricted diet

You may not qualify if:

  • Abnormal kidney (including kidney stones in the 5 years prior to study entry or creatinine clearance less than 50 ml/min/1.73 m2 of body surface area) or liver disease
  • Currently taking medications that might affect potassium
  • Intra-articular injections within 4 weeks prior to study entry
  • Current peptic ulcer disease
  • History of alcohol or substance abuse
  • Active infection, or chronic or persistent infection that might worsen with immunosuppressive treatment (e.g., HIV, hepatitis B virus, hepatitis C virus, tuberculosis \[TB\])
  • Known coronary artery disease or significant cardiac arrhythmias or severe congestive heart failure (New York Heart Association \[NYHA\] classes III or IV)
  • Definitive diagnosis of another autoimmune rheumatologic disease (e.g., systemic lupus erythematosus \[SLE\], scleroderma, primary Sjogren's syndrome, primary vasculitis)
  • History of cancer. Participants with previous resected basal or squamous cell carcinoma, treated cervical dysplasia, or treated in situ Grade I cervical cancer within 5 years prior to study entry are not excluded.
  • Any condition or treatment (including biologic therapies) that, in the opinion of the investigator, may place the participant at unacceptable risk during the study
  • Pregnancy
  • Vegetarian
  • Use of estrogen replacement therapy
  • Current use of diuretics, beta-blockers, anabolic drugs (steroids or other), angiotensin converting enzyme (ACE) inhibitors, or angiotensin receptor blockers (ARBs), etc, or any drug (s) other than drugs indicated for the purpose of RA therapy which is (are) known to effect serum potassium levels
  • Hyperparathyroidism
  • +4 more criteria

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (2)

Division of Rheumatoloy, Sina Teaching Hospital, Tabriz Medical Sciences University

Tabriz, East Azerbaidjan, Iran

Location

Sheikh-ol-Raees Ultra Specialized Clinic

Tabriz, East Azerbaidjan, Iran

Location

Related Publications (5)

  • Weber CE. Copper response to rheumatoid arthritis. Med Hypotheses. 1984 Dec;15(4):333-48. doi: 10.1016/0306-9877(84)90150-6.

    PMID: 6152006BACKGROUND
  • Weber CE. Corticosteroid regulation of electrolytes. J Theor Biol. 1983 Oct 7;104(3):443-9. doi: 10.1016/0022-5193(83)90116-9.

    PMID: 6656267BACKGROUND
  • Weber CE. A proposal for an experiment of potassium on rheumatoid arthritis. Clin Exp Rheumatol. 1983 Apr-Jun;1(2):184-6. No abstract available.

    PMID: 6398157BACKGROUND
  • Rastmanesh R, Abargouei AS, Shadman Z, Ebrahimi AA, Weber CE. A pilot study of potassium supplementation in the treatment of hypokalemic patients with rheumatoid arthritis: a randomized, double-blinded, placebo-controlled trial. J Pain. 2008 Aug;9(8):722-31. doi: 10.1016/j.jpain.2008.03.006. Epub 2008 May 12.

  • Rastmanesh R. Psoriasis and vegetarian diets: a role for cortisol and potassium? Med Hypotheses. 2009 Mar;72(3):368. doi: 10.1016/j.mehy.2008.09.031. Epub 2008 Nov 4. No abstract available.

Related Links

MeSH Terms

Conditions

Arthritis, RheumatoidPain

Condition Hierarchy (Ancestors)

ArthritisJoint DiseasesMusculoskeletal DiseasesRheumatic DiseasesConnective Tissue DiseasesSkin and Connective Tissue DiseasesAutoimmune DiseasesImmune System DiseasesNeurologic ManifestationsSigns and SymptomsPathological Conditions, Signs and Symptoms

Study Officials

  • Reza Rastmanesh, Ph.D.

    National Nutrition and Food Sciences Technology Institute

    STUDY CHAIR

Study Design

Study Type
interventional
Phase
phase 1
Allocation
RANDOMIZED
Masking
QUADRUPLE
Who Masked
PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
Purpose
SUPPORTIVE CARE
Intervention Model
PARALLEL
Sponsor Type
OTHER

Study Record Dates

First Submitted

April 17, 2007

First Posted

April 18, 2007

Study Start

February 1, 2007

Primary Completion

April 1, 2007

Study Completion

April 1, 2007

Last Updated

February 6, 2009

Record last verified: 2009-02

Locations