Creatine supplementation to treat "muscle wasting" in rheumatoid arthritis patients

INTERVENTION: The intervention will be of a nutritional supplement: creatine. Participants will be randomly assigned to either a Cr or placebo supplementation group. 12 week oral Cr supplementation with a subsequent 12 week follow up. CONDITION: Rheumatoid Arthritis ; Musculoskeletal Diseases ; Rheumatoid arthritis, unspecified PRIMARY OUTCOME: Objectively assessed whole body function ‐ measured via the objective physical functional tests at Baseline, Day 6. Week 12 and Week 24 SECONDARY OUTCOME: 1. Body composition ‐ measured via Dual‐energy X‐ray absorptiometry (DEXA) scan at all time points ‐ Baseline, Day 6. Week 12 and Week 24; 2. Muscle strength ‐ measured via the objective physical functional tests at Baseline, Day 6. Week 12 and Week 24; 3. Muscle biochemistry ‐ analysed from fasting blood samples taken at Baseline, Week 12 and Week 24. Also analysed from muscle biopsy's (if consented) taken at Baseline and Week 12. INCLUSION CRITERIA: All volunteers have to: 1. Fulfill the American Rheumatism Association 1987 revised criteria for the diagnosis of RA 2. Be functional class I or II 3. Be age 18 years or over, either sex