Correlations of 25-hydroxyvitamin D3 level in patients with ulcerative colitis with inflammation level, immunity and disease activity.

OBJECTIVE: To investigate the correlations between 25-hydroxyvitamin D3 (25-OHD3) level in patients with ulcerative colitis (UC) and inflammation level, immunity, disease activity.

PATIENTS AND METHODS: The serum level of 25-OHD3, inflammation status, immunity level and disease activity in patients (n=122) with UC in our hospital from 2015 to October 2017 were evaluated and analyzed.

RESULTS: The levels of inflammatory factors [C-reactive protein (CRP) and tumor necrosis factor-α (TNF-α)] in low 25-OHD3 group were higher than those in non-low 25-OHD3 group (p<0.01 and p<0.05), and both expressions of CRP and TNF-α in patients presented linearly negative correlations with the level of 25-OHD3 (r²=0.8351, r²=0.7298). There were no significant differences in the levels of immunoglobulin G (IgG) and complement C3 in low 25-OHD3 group compared with those in non-low 25-OHD3 group (p>0.05). There was an overall decreasing trend of 25-OHD3 level as disease activity increased, and there were statistically significant differences in the levels of 25-OHD3 in each group in remission period and mild, moderate and severe activity periods. The disease activity score of patients showed a linearly negative correlation with the level of 25-OHD3 (r²=0.8465). The level of 25-OHD3 in the observation group (treated with mesalazine combined with vitamin D) was increased with the time of medication, and the level was higher than that in the control group (treated with mesalazine only). CRP, TNF-α, and disease activity score in the observation group were decreased with the time of medication, and the level was lower than that in the control group.

CONCLUSIONS: The level of 25-OHD3 in UC patients is linearly correlated with the level of inflammation and disease activity. At the same time, combined treatment with vitamin D improves the reducing level of inflammation and limits the disease activity. Therefore, 25-OHD3 can be used in the assessment of the level of inflammation and disease activity, and as a potential tool in the treatment.