Thyroid dysfunction in Turkish patients with chronic hepatitis C receiving peginterferon plus ribavirin in the period of 2005-2010

Abstract

Interferon-α based therapy for chronic hepatitis C (CHC) is associated with thyroiditis and thyroid dysfunction (TD). This study investigated whether TD during pegylated interferon-α (PEG-IFN) plus ribavirin treatment favors sustained viral response (SVR), and also the association between TD and PEG-IFN formulations. This retrospective study was performed in CHC patients who had received PEG-IFN plus ribavirin and had been followed for six months after treatment. Several factors were compared between patients with and without TD. 119 patients were included in the study. De novo incidence of TD was found to be 16.8%, and 16 of the 18 patients with TD achieved SVR. Although this rate was higher than patients without TD according to univariate analysis, logistic regression analysis revealed that there was not a significant association between TD and SVR, whereas baseline thyroperoxidase antibody (anti-TPO) positivity was the only significant predictor of TD. Moreover, TD was not associated with PEG-IFN type. Both interferon-α and hepatitis C virus (HCV) contribute to TD during antiviral therapy. It seems that there is no association between thyroid toxicity and viral clearance or type of PEG-IFN; however, anti-TPO positivity before treatment is the strongest predictor for TD during antiviral therapy.

Thyroid Dysfunction Related to Interferon in Turkish Patients with Viral Hepatitis: Incidence and Influencing Factors

“…As we have mentioned before, gender and age are among factors that are effective in TD development. Especially in terms of gender, presence of a more reactive immune system in females in comparison to males may explain more frequent occurrence of TD associated with IFN, but while many studies support this (7,10,11,18) some studies did not find a significant association (12,20,21). Age (over 40 years) and female gender were found to be statistically independent risk factors in TD development in our study.…”

“…When former studies are examined, results showing that factors such as CHC genotype, thyroid auto-antibodies, and response to IFN therapy may be effective in TD development are observed to be reported (12,(16)(17)(18)(19)(20)(21)(22).…”

Clinical Value of Thyrotropin Receptor Antibodies for the Differential Diagnosis of Interferon Induced Thyroiditis

“…Peg-IFNα plus RBV treatment is associated with a wide range of side effects including influenzalike symptoms, hematologic abnormalities, neuropsychiatric disorders and thyroid dysfunction [5]. The incidence of thyroid dysfunction induced by interferon therapy has been reported to be between 4.6 and 84.8 % [6][7][8][9][10][11][12][13][14][15]. To date, several studies have described different forms of thyroid dysfunction and predisposing factors.…”

“…The incidence of "de novo" TRAb development was 8 %. The majority of studies on interferon-induced thyroid disorders did not analyze the development of TRAb and focused on Tg-Ab and TPO-Ab [6,7,9,11,[13][14][15]. The few studies that evaluated the "de novo" development of TRAb during treatment reported an incidence between 0 and 1.5 %; however, it must be emphasized that they used first-generation immunoassays, and thus the higher incidence found in our study might be related to the use of a more sensitive test.…”

“…Several studies have reported wide variability in the development of thyroid dysfunction, ranging from 0 % to 27.8 % for the "de novo" development of thyroid autoantibodies and 4.6-84.8 % for thyroid dysfunction [7][8][9][10][11][12][13][14][15]. This variability can be explained by several factors: differences in the baseline characteristics of the population such as gender or ethnicity, periodicity of hormonal tests during treatment or diagnostic criteria used for thyroid dysfunction classification [29].…”