The Usefulness of Serum Vitamin D Levels in the Assessment of IBD Activity and Response to Biologics

Abstract

The main role of vitamin D is calcium homeostasis and bone metabolism, although its activity as an immuno-modulator and its anti-inflammatory effect is well-known. Low blood vitamin D levels are common among patients with inflammatory bowel disease (IBD). Whether low vitamin D levels could affect the disease activity or it is an effect of a worse condition of the disease is still unclear. This study aimed to investigate the role of blood vitamin D levels to identify the clinical, endoscopic, and histological activity in a cohort of patients with ulcerative colitis (UC) or Crohn’s disease (CD) on therapy with biological drugs. In this retrospective cohort study, 50 IBD patients (24 UC and 26 CD) that underwent colonoscopy from January 2017 to January 2020 with a concomitant serological evaluation of vitamin D were included. Patients with clinical, endoscopic, and histological activity and those who lost their clinical response to the biological drug had lower vitamin D levels compared to patients in remission or patients that did not change therapeutic regimens. A receiver operating characteristic (ROC) analysis and Youden’s Index were performed to assess the optimal vitamin D levels to identify patients with the active disease. The ROC analysis showed an area under the curve (AUC) of 0.709 (p = 0.005; confidence interval (CI): 0.564–0.829), 0.769 (p < 0.001; CI: 0.628–0.876), and 0.810 (p < 0.001; CI: 0.670–0.910) for the clinical, endoscopic, and histological outcomes, respectively. The optimal vitamin D cut-off was ≤25 ng/mL. The vitamin D level is an additional useful tool in the evaluation of IBD patients with good accuracy to predict their endoscopic and histological activity and clinical response to biologics.

Seven Weeks of High-Dose Vitamin D Treatment Reduces the Need for Infliximab Dose-Escalation and Decreases Inflammatory Markers in Crohn’s Disease during One-Year Follow-Up

“…Mucosal healing is perceived an important treatment goal in CD [27]. Another IBD study demonstrated that vitamin D deficiency was associated with disease activity and loss of clinical response to biological treatment [28].…”

Vitamin D in Inflammatory Bowel Diseases. Mechanisms of Action and Therapeutic Implications

“…Reduced risk of postoperative endoscopic recurrence in patients with CD who underwent surgery has been reported in an observational study in patients with vitamin D > 30 ng/mL (OR 0.22, 95% CI 0.07-0.66, p = 0.006) [99]. Thus, vitamin D has been proposed as a potential biomarker of disease activity [98,100]. This is, at best, debatable, as vitamin D concentration reflects changes occurring over relatively long periods.…”

“…A correlation between vitamin D levels and disease activity is also present [30]. Levels of 25(OH)D ≤ 25 ng/mL in a retrospective study had an AUC of 0.79-0.81 for the identification of endoscopic and histologic activity [98]. Reduced risk of postoperative endoscopic recurrence in patients with CD who underwent surgery has been reported in an observational study in patients with vitamin D > 30 ng/mL (OR 0.22, 95% CI 0.07-0.66, p = 0.006) [99].…”

“…Normal vitamin D levels at induction with anti-TNF-α are associated with 2.64 increased odds of remission at 3 months compared to patients with low vitamin D levels (OR 2.64, 95% CI 1.31-5.32, p = 0.0067) [118]. Vitamin D ≤ 25 ng/mL identified patients (6/6) losing response to biological drugs (6/50) [98]. The same holds for an increased risk of primary non-response to vedolizumab (OR 26.10, 95% CI 14.30-48.90, p < 0.001) and failure at 1-year follow-up (OR 6.10, 95% CI 3.06-12.17, p < 0.001) [119].…”

Cannabinoid Therapeutic Effects in Inflammatory Bowel Diseases: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

“…However, the ultimate goal to achieve a stable clinical remission is far from being reached. In this scenario, a growing number of adjunctive therapies, such as vitamin D and probiotics, has been proposed over the years, integrating the current standard of care in the hope of achieving clinical benefits [ 12 , 13 , 14 ].…”