Association between hepcidin levels and inflammatory bowel disease: A systematic review and meta‐analysis of observational studies

Abstract

Hepcidin has a crucial role in iron homeostasis upon inflammatory conditions such as inflammatory bowel disease (IBD). Thus, we conducted a systematic review and meta‐analysis to determine the overall association between serum hepcidin concentrations and IBD. Based on the preferred reporting items for systematic review and meta‐analysis (PRISMA) protocols, an electronic literature search was conducted on PubMed/MEDLINE, Scopus, and Web of Science until June 2020. Studies were deemed eligible for inclusion if they met the following criteria: (1) diagnosis of IBD, (2) observational design, and (3) measured serum hepcidin and prohepcidin concentrations in IBD patients and control group. Overall, 10 studies including 1184 participants were evaluated. Random‐effects meta‐analysis revealed that subjects with IBD had 7.22 ng/mL (95% CI: 2.10, 12.34; p = .006) higher serum hepcidin concentrations compared to control groups. A nonsignificantly lower serum prohepcidin concentration (0.522 ng/mL, 95% CI: −1.983 to 0.939; p = .484) was found for IBD patients compared to healthy subjects. However, there was significant heterogeneity among the studies regarding both hepcidin (I2 = 98%, p < .001) and prohepcidin levels (I2 = 96%, p < .001), respectively. In an age‐based subgroup analysis, patients aged ≥18 years with IBD displayed higher serum hepcidin levels when compared to healthy individuals (22.36 ng/mL, 95% CI, 2.12–42.61; p = .030). Hepcidin concentrations are elevated in subjects with IBD; however, the clinical relevance of this finding requires further evaluation in future investigations as the increase is relatively small compared to the wide range of normal hepcidin values.