Serum Globulin Is Associated with Endoscopic Findings and Mucosal Healing in Japanese Patients with Ulcerative Colitis

Background Serum globulin is an inflammation marker. To date, no evidence regarding the association between serum globulin and disease activity in patients with ulcerative colitis has been reported. Aims We evaluated the association between serum globulin and endoscopic activity in patients with ulcerative colitis. Methods Serum globulin was divided into tertiles based on the distribution of study subjects (low globulin, <= 2.7 g/dl (reference); moderate globulin, 2.7-3.1 g/dl; and high globulin, > 3.1 g/dl). A single endoscopic specialist evaluated the endoscopic findings, and mucosal healing was based on Mayo endoscopic subscore. Results A total of 277 patients with ulcerative colitis were included in the study. Serum globulin was independently positively associated with diminished or absent vascular markings [moderate: adjusted odds ratio (OR) 3.70 (95% confidence interval, CI: 1.82-7.88) and high: adjusted OR 2.40 (95%CI: 1.20-4.94), p for trend = 0.005]. A similar positive association between globulin and erosion was found [high: adjusted OR 2.00 (95%CI: 1.05-3.86)]. Serum globulin was independently inversely associated with mucosal healing [moderate: adjusted OR 0.37 (95%CI: 0.18-0.73) and high: adjusted OR 0.31 (95%CI: 0.14-0.64), p for trend = 0.001] and adjusted partial mucosal healing [moderate: OR 0.51 (95%CI: 0.26-0.98), p for trend = 0.048]. The inverse association between globulin and mucosal healing was significant in the low but not the high C-reactive protein group. Conclusions In patients with ulcerative colitis, serum globulin was significantly positively associated with endoscopic activity, and was significantly inversely associated with mucosal healing, especially in the low C-reactive protein group.