Objective. To determine the prevalence and associated factors of kidney disease in Korean rheumatoid arthritis (RA) patient, and describe the profile of RA drugs prescribed in RA patients.
Methods. A total of 284 patients at the division of rheumatology with confirmed RA were prospectively included in this study from May 1 to August 31, 2008. Renal function was assessed using Cockcroft-Gault (CG) and abbreviated Modification of Diet in Renal Disease (aMDRD) study formulae, and classified by the National Kidney Foundation (NKF) classification. Comparisons was were performed by the two sample t-test, chi-square-test and binary logistic regression analysis. Results. Of 281 patients with RA, only 7 (2.5%) patients had abnormal serum creatinine (sCr) levels. According to the NFK classification, the prevalence of kidney disease using aMDRD and CG formula was 23.8% and 31.7%, respectively. Among the patients with eGRF ＜60 mL/min/ m² according to aMDRD or CG formulae, 91.8∼100% received at least one drug that was potentially nephrotoxic. RA patients with renal dysfunction was associated with advanced age, body mass index (BMI), antinuclear antibody (ANA).
Conclusion. Estimation of renal function with CG or aMDRD formulae is important in RA patients, particularly in those with low BMI or old age. Also, appropriate dosage adjustment is needed in patients with renal dysfunction.

Keywords: Rheumatoid arthritis, Kidney disease