Systematic Reviews
Copyright ©The Author(s) 2017. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Hepatol. Feb 18, 2017; 9(5): 278-287
Published online Feb 18, 2017. doi: 10.4254/wjh.v9.i5.278
Influence of vitamin D on liver fibrosis in chronic hepatitis C: A systematic review and meta-analysis of the pooled clinical trials data
Alia S Dadabhai, Behnam Saberi, Katie Lobner, Russell T Shinohara, Gerard E Mullin
Alia S Dadabhai, Behnam Saberi, Katie Lobner, Gerard E Mullin, Division of Gastroenterology and Hepatology, the Johns Hopkins University School of Medicine, Baltimore, MD 21224, United States
Russell T Shinohara, Department of Biostatistics and Epidemiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, United States
Author contributions: Dadabhai AS, Saberi B and Mullin GE contributed equally to the data evaluation, manuscript preparation, editing, figures, and final submission; Shinohara RT provided biostatistics methodology oversight, data extractions and meta-analysis with pooled data figure preparation and manuscript preparation and editing; Lobner K provided informatics methodology support, conducted the literature search, and reviewed and edited the manuscript.
Conflict-of-interest statement: All the authors declare that they have no competing interests.
Data sharing statement: Technical appendix, statistical code, and dataset are available from the corresponding author at adadabh1@jhmi.edu.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Alia S Dadabhai, MD, Assistant Professor, Division of Gastroenterology and Hepatology, the Johns Hopkins University School of Medicine, 4940 Eastern Ave A504, Baltimore, MD 21224, United States. adadabh1@jhmi.edu
Telephone: +1-410-5507857 Fax: +1-410-5507861
Received: November 16, 2016
Peer-review started: November 21, 2016
First decision: December 1, 2016
Revised: December 14, 2016
Accepted: January 2, 2017
Article in press: January 3, 2017
Published online: February 18, 2017
Abstract
AIM

To investigate the relationship between vitamin D and liver fibrosis in hepatitis C-monoinfected or hepatitis C virus (HCV)-human immunodeficiency virus (HIV) co-infected patients.

METHODS

Pertinent studies were located by a library literature search in PubMed/Embase/Cochrane/Scopus/LILACS by two individual reviewers. Inclusion criteria: (1) studies with patients with HCV or co-infected HCV/HIV; (2) studies with patients ≥ 18 years old; (3) studies that evaluated liver fibrosis stage, only based on liver biopsy; and (4) studies that reported serum or plasma 25(OH)D levels. Studies that included pediatric patients, other etiologies of liver disease, or did not use liver biopsy for fibrosis evaluation, or studies with inadequate data were excluded. Estimated measures of association reported in the literature, as well as corresponding measures of uncertainty, were recorded and corresponding odds ratios with 95%CI were included in a meta-analysis.

RESULTS

The pooled data of this systematic review showed that 9 of the 12 studies correlated advanced liver disease defined as a Metavir value of F3/4 with 25(OH) D level insufficiency. The meta-analysis indicated a significant association across studies.

CONCLUSION

Low vitamin D status is common in chronic Hepatitis C patients and is associated with advanced liver fibrosis.

Keywords: Vitamin D, Liver fibrosis, Hepatitis C virus, Chronic hepatitis C

Core tip: Vitamin D levels are associated with more advanced fibrosis in chronic hepatitis C.