Published online Oct 14, 2026. doi: 10.3748/wjg.121569
Revised: April 17, 2026
Accepted: May 13, 2026
Published online: October 14, 2026
Processing time: 162 Days and 20.6 Hours
Red cell distribution width (RDW) has emerged as a potential inflammatory marker in various chronic inflammatory conditions, yet its role in inflammatory bowel disease (IBD) remains insufficiently understood.
To investigate the association between RDW parameters [RDW-coefficient of variation (RDW-CV) and RDW-standard deviation (RDW-SD)] and disease acti
This retrospective study included 455 patients diagnosed with IBD (365 UC, 90 CD) who were followed at a tertiary referral center between 2018 and 2025. Di
In CD, RDW-CV values were significantly higher in patients with moderate disease activity compared with those in remission and mild activity groups (P = 0.02). However, this significance was observed only across activity categories; when disease activity was dichotomized as remission vs active disease, RDW-CV did not show a significant difference (P = 0.25). In UC, RDW-CV was progressively higher in moderate and severe disease compared with remission and mild disease (P < 0.001). When evaluated as remission vs active disease, RDW-CV was also significantly higher in active UC (P = 0.002). RDW-SD did not show significant differences across activity groups in either disease.
RDW-CV is associated with increased disease activity in UC and may partially reflect disease severity in CD. As an inexpensive and easily accessible biomarker, RDW may provide supportive information when evaluating inflammatory burden in IBD; however, prospective multicenter studies are needed to validate its clinical utility. These findings suggest that RDW-CV may serve as a practical adjunct biomarker for disease activity assessment, particularly in settings where endoscopic evaluation is not readily available.
Core Tip: Red cell distribution width (RDW) is an inexpensive and widely available parameter reflecting systemic inflammation. In this study, RDW-coefficient of variation was significantly associated with disease activity in ulcerative colitis, suggesting its potential as a supportive biomarker in clinical practice. However, its utility in Crohn’s disease appears limited.