Patients with rheumatoid arthritis (RA) are more likely to develop reduced estimated glomerular filtration rate (eGFR) than the general population.1 Decreased eGFR is associated with a higher risk of cardiovascular disease and mortality independent of traditional cardiovascular risk factors in RA.2,3 Because there is evidence that the inflammatory process might contribute to decreased kidney function,4,5 chronic inflammation might cause kidney damage in patients with RA. Thus, we aimed to identify the associations of disease activity with eGFR in patients with RA.