Thyroid Disturbance in Patients with Chronic Hepatitis C Infection: A Systematic Review and Meta-analysis

Abstract

Background & Aims: The involvement of thyroid autoimmunity and dysfunction in patients with chronichepatitis C virus (HCV) infection before interferon-α (IFN-α) therapy remains controversial. We performedthis meta-analysis to evaluate the association of HCV infection with the presence of anti-thyroid antibodiesand dysthyroidism. Methods: A literature search was carried out to collect articles dated up to August 2015 to identify observationalstudies which compared the prevalence of anti-thyroid antibodies and thyroid dysfunction in IFN-α naïvechronic HCV-infected subjects with non-HCV infected controls. Random-effect or fixed-effect meta-analyseswere applied and results reported as odds ratios (ORs) with 95% confidence intervals (CIs). Results: Twelve studies were included, involving 1,735 HCV-infected and 1,868 non-HCV infected subjects.Pooled anti-thyroid antibody prevalence tended to be higher in HCV-infected subjects. The prevalence ofanti-thyroglobulin antibody (TGAb), anti-thyroid peroxidase antibody (TPOAb), anti-thyroid microsomalantibody (ATMA) were 2.40-fold, 1.96-fold and 1.86-fold higher in HCV-infected subjects than in controls,respectively. The prevalence of hypothyroidism also differed by HCV infection status, with a pooled risk of3.10 (95%CI: 2.19-4.40) in HCV-infected subjects. However, the results did not show a significant differencein the prevalence of hyperthyroidism between the two groups.Conclusion: Chronic HCV infection may be an independent risk factor for thyroid disturbance. It is advisablefor the clinicians to monitor both thyroid antibodies and function in the course of chronic HCV infection,independent of IFN-α treatment. Abbreviations: AITD: autoimmune thyroid disease; ATMA: anti-thyroid microsomal antibody; CHC:chronic hepatitis; GD: Graves’ disease; HCV: hepatitis C virus; HT: Hashimoto’s thyroiditis; IFN-α: interferonalpha;NOS: Newcastle-Ottawa quality assessment scale; T3: triiodothyronine; T4: thyroxine; TGAb: antithyroglobulinantibody; TPOAb: anti-thyroid peroxidase antibody.