Adiponectin levels among patients with chronic hepatitis B and C infections and in response to IFN-α therapy

Aims: The study was designed to survey the change of adiponectin levels before and after interferon-alpha (IFN-alpha) therapy in patients with chronic hepatitis B and C infections. Methods: Twenty-one biopsy-proved patients with chronic hepatitis B (10 cases) and hepatitis C (11 cases) were given IFN-alpha for a total of 24 weeks. Fasting plasma glucose, insulin and adiponectin levels were obtained before and 12 weeks after completion of IFN-alpha therapy. Insulin suppression test was conducted before and within 1 week after IFN-alpha therapy. Results: The change of adiponectin levels differed significantly between responders (eight cases) and non-responders (13 cases) to IFN-alpha treatment (-4.8 +/- 2.2 vs. 0.5 +/- 1.0 mu g/ml, P=0.03). After adjusting for age, gender and change in body mass index, the study found the change of adiponectin levels still significantly related to the response to IFN-alpha (P=0.04). When hepatitis B virus (HBV) and hepatitis C virus (HCV)-infected patients were separately analyzed, the adiponectin levels reported a trend to decrease in HCV responders (11.9 +/- 3.2 vs. 10.8 +/- 3.0 mu g/ml, P=0.02, n=4) and HBV responders (17.7 +/- 4.1 vs. 9.2 +/- 1.0 mu g/ml, P=0.10, n=4). In addition, a significant decrease of steady-state plasma glucose in insulin suppression test was noted in responders (13.6 +/- 1.8-11.7 +/- 1.2 mmol/l, P=0.03), but not in non-responders (12.3 +/- 1.1-11.0 +/- 1.0 mmol/l, P=0.20), after IFN-alpha therapy. Conclusions: IFN-alpha resulted in a decrease of serum adiponectin levels but an improvement of insulin resistance in responders to the treatment. The result contradicts previous concept of the relationship between insulin resistance and adiponectin levels. Whether and how the augmented immune response, which was supposed to result from the disappearance or the profound down-regulation of the virus or viral antigens in responders to IFN-alpha treatment, contributes to the lowering of adiponectin levels needs to be further investigated.