[Explore the influence of vitamin D supplementation on clinical efficacy and drug retention rate of vedolizumab in patients with ulcerative colitis].

Objectives: To analyze the influence of vitamin D supplementation on clinical efficacy and drug retention rate of vedolizumab (VDZ) in patients with ulcerative colitis (UC). Methods: Retrospective study. By retrieving the clinical database of the Second Affiliated Hospital of Wenzhou Medical University, the patients with moderately to severely active UC were collected, who underwent VDZ treatment from January 2020 to June 2022. The modified Mayo score and Mayo endoscopic score (MES) were employed to evaluate disease activity and intestinal inflammation in UC patients, respectively. According to whether vitamin D was supplemented during VDZ treatment, the patients were divided into supplementary group and non-supplementary group. According to baseline serum 25(OH) D level, UC patients were divided into vitamin D deficiency group and non-deficiency group. According to whether vitamin D was supplemented, the patients of each group were divided into supplementary subgroup and non-supplementary subgroup, respectively. The clinical response rate, clinical remission rate and mucosal healing rate at week 30 after receiving VDZ treatment and the retention rate of VDZ at the 72nd week were observed. The effect of baseline serum 25 (OH) D level on the efficacy of vitamin D supplementation was analyzed by chi-square test. The effects of vitamin D supplementation on the clinical efficacy and drug retention of VDZ in UC were analyzed by chi-square test and Kaplan-Meier curve, respectively. Results: A total of 80 patients with moderately to severely active UC, who were aged (39.4±13.0) years(18-75 years), 37 male and 43 female, were included. There were 43 cases in supplementary group and 37 cases in non-supplementary group. There were 59 cases in the deficiency group, including 32 cases in the supplementary subgroup and 27 cases in the non-supplementary subgroup. There were 21 cases in the non-deficiency group, including 11 cases in the supplementary subgroup and 10 cases in the non-supplementary subgroup. At week 30, the average level of serum 25(OH) D was shown to be higher in supplementary group than that at week 0 [(24.5±5.4) vs (17.7±6.7) µg/L, P<0.001]. At week 30, in contrast with non-supplementary group, erythrocyte sedimentation rate(ESR)[75.0% (24.3%, 86.7%) vs 32.7% (-2.6%, 59.3%), P=0.005] and modified Mayo score [(4.7±2.8) vs (2.3±2.7) points, P<0.001] and MES score [(1.2±1.1) vs (0.4±0.9) points, P=0.001] were significantly reduced, clinical response rate [79.1%(34/43) vs 56.8%(21/37), P=0.032], clinical remission rate [67.4%(29/43) vs 29.7%(11/37), P=0.001] and mucosal healing rate [72.1%(31/43) vs 37.8%(14/37), P=0.002] were higher. At week 72, drug retention rate of VDZ was shown to be higher in supplementary group than in non-supplementary group [55.8%(24/43) vs 27.0%(10/37), P=0.004]. The further analysis showed that vitamin D supplementation could only improve clinical response rate[71.9%(23/32) vs 44.4%(12/27), P=0.033], clinical remission rate[62.5%(20/32) vs 14.8%(4/27), P<0.001], mucosal healing rate[68.8%(22/32) vs 22.2%(6/27), P<0.001] and drug retention rate [53.1%(17/32) vs 13.8%(4/27), P=0.001] in the patients with vitamin D deficiency. Conclusion: Vitamin D supplementation contributes to improving clinical response rate, clinical remission rate, mucosal healing rate and drug retention rate of VDZ in UC patients.