Combination of Methotrexate and Prednizone Decreases Circulating Concentrations of Interleukin 1Beta and Interleukin 6 in Patients with Rheumatoid Arthritis. Poor Correlation of Cytokine Suppression with Clinical Improvement

Objective To evaluate the effect of methotrexate (MTX) in combination with prednizone on cytokine levels, acute phase proteins and thiobarbituric acid reactive substances (TBAR - an indicator of peroxidative damage to tissue lipids) in the blood of rheumatoid arthritis (RA) patients and to investigate their assgciations with clinical disease activity. Methods We measured blood concentrations of interleukin-1 R (IL-1p), interleukin- 6 (IL-6), TBARs and classical clinical and laboratory indices of disease activity in 36 RA subjects before and after 3 and 6 month treatment with MTX and prednizone. Only RA subjects who stopped any disease-modifying anti rheumatic drugs treatment for last 3 months were included in the study. Baseline cytokine and TBARs levels were compared with those obtained with 20 healthy controls. Results- Compared to controls RA subjects had elevated levels of circulating IL-1beta (63.3 ±47.6 vs 13.7 ± 7.8 pg/ml, p< 0.01), IL-6 (147.2 ± 76.5 vs 15.9 ± 13.3 pg/ml, p< 0.001) and TBARs (3.11 ± 0.42 vs 1.34 ± 0.45 nmol/1, p< 0.001) concentrations. MTX in combination with prednizone improved patient clinical status that was accompanied by 1.96-, 1.25-, and 1.35-fold decrease in IL-1beta, IL-6 and TBARs after 6 month treatment (p