Zinc Deficiency is Associated with Poor Clinical Outcomes in Patients with Inflammatory Bowel Disease

Background: Zinc plays a pivotal role in wound repair, tissue regeneration, and the immune response. Although zinc deficiency is common in patients with inflammatory bowel disease (IBD), the impact of low serum zinc levels on disease course is not known. Methods: Patients enrolled in a prospectively collected IBD registry with at least 2 serum zinc measurements were included in the analysis. Using a logistic regression model, rates of IBD-related surgeries, IBD-related hospitalizations, and IBD-related complications were evaluated after a diagnosis of zinc deficiency (serum concentration <0.66 mu g/ mL) compared with those with normal zinc concentrations. In patients who were zinc deficient, outcomes were also analyzed between those who had normalization of zinc levels within 12 months and those who remained deficient. Results: A total of 773 patients with Crohn's disease (CD) and 223 with ulcerative colitis (UC) were included in the analysis. After adjusting for covariates, zinc deficiency was associated with an increased risk of subsequent hospitalizations, surgeries, and disease-related complications in patients with CD and UC (CD: hospitalizations, odds ratio 1.44, 95% confidence interval [1.02-2.04]; surgeries, 2.05 [1.38-3.05]; complications, 1.50 [1.04-2.15]; UC: hospitalizations, 2.14 [1.07-4.29]; surgeries, 1.64 [0.59-4.52]; complications, 1.97 [0.94-4.11]). Normalization of zinc was associated with improvement in these outcomes in patients with both CD and UC. Conclusions: Patients with IBD with serum zinc deficiency are more likely to have adverse disease-specific outcomes. As these outcomes improve with normalization of zinc, the results from this study support the role for close monitoring and replacement of zinc in patients with IBD.