Impact of concomitant chronic kidney disease on hospitalised infections and remission in patients with rheumatoid arthritis: results from the IORRA cohort

Abstract

ABSTRACT Objectives To investigate the impact of concomitant chronic kidney disease (CKD) on unfavourable clinical events and remission in Japanese patients with rheumatoid arthritis (RA). Methods We included 5103 patients with RA and CKD from the Institute of Rheumatology Rheumatoid Arthritis (IORRA) cohort in 2012. CKD stages were classified into four groups: CKD with normal eGFR ≥60 ml/min/1.73 m2 and proteinuria; mild CKD, eGFR ≥45 to < 60; moderate CKD, eGFR ≥30 to < 45; and severe CKD, eGFR <30. We assessed the association between concomitant CKD and the occurrence of unfavourable clinical events or achieving remission during a 5-year observational period. Results Of the 5103 patients with RA, 686 (86.6%) had CKD. Concomitant CKD was associated with hospitalised infections [adjusted hazard ratio (aHR) 1.52, 95% confidence interval (CI) 1.07–2.13, p = .02], especially in the moderate to severe CKD group (aHR 1.93, 95% CI 1.12–3.13, p = .02). Of all subjects, 2407 (47.2%) had active RA at baseline and 401 (16.7%) had CKD. Concomitant CKD was also associated with the failure of achieving remission (aHR 0.82, 95% CI 0.68–0.99, p = .04). Conclusions Concomitant CKD was a risk factor for hospitalised infections in Japanese patients with RA and failure of achieving remission in patients with active RA.