25-Hydroxyvitamin D Concentrations and Clostridium difficile Infection: A Meta-Analysis

Background: Well-known risk factors for Clostridium difficile infection (CDI) are exposure to antibiotics and gastric acid suppressants. Recent studies have provided some evidence of an association between hypovitaminosis D and the risk of CDI. Therefore, this meta-analysis aimed to pool all the existing evidence to investigate the association between 25-hydroxyvitamin D (25[OH]D) and CDI. Methods: A systematic search was conducted in 3 databases (PubMed, Embase, and Web of Sciences) for epidemiological studies that examined the association between mean 25(OH)D concentrations and CDI as well as between 25(OH)D status and CDI severity or recurrence. 25(OH)D status was defined as “lower” or “higher” at a threshold concentration of