Vitamin D deficiency associated with Crohn\u2019s disease and ulcerative colitis: a meta-analysis of 55 observational studies

Xi-Xi Li,Yang Liu,Zhen-Dong Huang,Jie Luo,Yan Fu,Chao Zhang

doi:10.1186/s12967-019-2070-5

Abstract

PurposeTo investigate the association of serum levels of 25(OH)D and 1,25(OH)2D3 in healthy and non-healthy controls with Crohn’s disease (CD) and ulcerative colitis (UC).MethodsThree electronic databases: PubMed, EMbase and EBSCOhost CINAHL, were searched for observational studies to measure the relationship between serum levels of vitamin D (VitD) and CD (or UC).ResultsFifty-five studies were included in the meta-analysis. We found that mean serum 25(OH)D levels in patients with CD were significantly lower than those in healthy controls (MD: − 3.17 ng/mL; 95% CI − 4.42 to − 1.93). Results from the meta-analysis examining 1,25(OH)2D3 levels in Crohn’s patients revealed higher levels in the CD group than in healthy (MD: 3.47 pg/mL; 95% CI − 7.72 to 14.66) and UC group (MD: 5.05 pg/mL; 95% CI − 2.42 to 12.52). Serum 25(OH)D levels were lower in the UC group than in the healthy control group (MD: − 2.52 ng/mL; 95% CI − 4.02 to − 1.02). In studies investigating the level of 1,25(OH)2D3 in UC and healthy control groups, the level of 1,25(OH)2D3 in the UC groups were found to be higher than that in the control groups (MD: 3.76 pg/mL; 95% CI − 8.36 to 15.57). However, the 1,25(OH)2D3 level in patients with UC was lower than that in CD groups (MD: − 6.71 pg/mL; 95% CI − 15.30 to 1.88). No significant difference was noted between CD patients and UC patients in terms of average serum 25(OH)D levels.ConclusionsThis study found that VitD levels were inversely related to CD and UC. Serum levels of 25(OH)D were lower in patients with CD and UC than in healthy people, and more than half of the patients had insufficient vitamin D levels. The serum level of 1,25(OH)2D3 in both the CD and UC groups was higher than that in healthy people.

Highlights

Inflammatory bowel disease (IBD), including the two major forms: Crohn’s disease (CD) and ulcerative colitis (UC), is a chronic, relapsing–remitting systemic disease that typically begins in young adulthood and lasts throughout life
Inclusion and exclusion criteria Studies were eligible for analysis if they met the following criteria: (1) all included studies were limited to observational investigations in English; (2) serum Vitamin D (VitD) levels were detected in CD or UC patients; (3) when several trials from the same authors were identified as duplicates, we only included the most recent trial with the largest number of patients or with a longer follow-up period
Overall, when all seven eligible studies [26, 29, 30, 34, 38, 46, 59] were analyzed using a random-effects model, the results showed that VitD levels were lower in patients with UC than in CD (MD: − 6.71 pg/mL; 95% confidence interval (CI) − 15.30 to 1.88) (Fig. 9)

Summary

Introduction

Inflammatory bowel disease (IBD), including the two major forms: Crohn’s disease (CD) and ulcerative colitis (UC), is a chronic, relapsing–remitting systemic disease that typically begins in young adulthood and lasts throughout life. Other studies have taken the opposite view of the relationship [15] between VitD and IBD and have left the controversy unresolved for patients with CD [16] and UC [17, 18]. To explore this controversy we performed a pooled meta-analysis to investigate and determine the status of VitD in the serum of healthy and non-healthy controls and to study the association between serum 25(OH)D and 1,25(OH)2D3 concentrations and an IBD diagnosis (both UC and CD)

Methods

Results

Discussion

Conclusion