Thyroid Dysfunction in Non-Interferon Treated Hepatitis C Patients Residing in Hepatitis Endemic Area

Association of thyroid dysfunction (TD) with interferon treatment of HCV is well known to clinicians. However, a few studies have highlighted the role of hepatitis C virus per se in the development of TD. The aim of this study was to know the prevalence of TD in non-interferon treated HCV infected patients referred for thyroid function testing.

Among 557 ELISA-positive HCV patients 446 (341 females, 105 males) were selected for this study. Serums FT₄, FT₃, and TSH were determined by radioimmunoassay method.

TD was detected in 15.2% of patients: 9.0% hypothyroidism and 6.3% hyperthyroidism. In increasing order subclinical hypothyroidism, overt hypothyroidism, overt hyperthyroidism, and subclinical hyperthyroidism were found in 4.7%, 4.3%, 3.6%, and 2.7% patients, respectively. Overall TD was more common in female than in male HCV patients but the difference was not significant (16.1% versus 12.4%; p = 0.648). Hyperthyroidism and subclinical hypothyroidism were slightly more common in female and overall hypothyroidism and overt hypothyroidism in male patients but the difference was not statistically significant (p > 0.05). The incidence of TD was relatively high in patients above 36 years (median age) but the difference was not statistically significant either collectively or in gender base groups (p > 0.05).

Prior to interferon treatment, HCV infection itself causes biochemical thyroid dysfunction in 15.2% of local HCV patients.