Serum levels of apoptosis inhibitor of macrophage are associated with hepatic fibrosis in patients with chronic hepatitis C

Background Apoptosis inhibitor of macrophage (AIM) and adipocytokines are involved in the metabolic syndrome, which has been putatively associated with the progression of chronic hepatitis C (CHC). However, the association between these cytokines and CHC is not fully elucidated. The aim of this study is to test whether serum levels of AIM and adipocytokines are associated with histological features, homeostasis model assessment-insulin resistance index (HOMA-IR), or whole body insulin sensitivity index (WBISI) in CHC patients. Methods Serum samples were obtained from 77 patients with biopsy-proven CHC. In 39 patients without overt diabetes mellitus, a 75 g oral glucose tolerance test (OGTT) was performed and HOMA-IR and WBISI were calculated. Results A serum AIM level of ≥1.2 μg/ml was independently associated with advanced hepatic fibrosis (F2 or F3) (odds ratio [OR], 5.612; 95% confidence interval [CI], 1.103–28.563; P = 0.038) based on a multivariate analysis, but there was no significant association between AIM and hepatic steatosis or inflammation. Furthermore, a serum leptin level of ≥8.6 ng/ml was independently associated with the presence of hepatic steatosis (≥5%) (OR, 6.195; 95% CI, 1.409–27.240; P = 0.016), but not hepatic fibrosis or inflammation. No relationship was observed between levels of adiponectin or resistin and hepatic histological parameters based on a multivariate analysis. Although serum levels of leptin, resistin, and adiponectin were significantly correlated with HOMA-IR and WBISI, there was no significant relationship between serum AIM levels and HOMA-IR or WBISI, respectively. Conclusion High serum levels of AIM in CHC patients are potentially related to advanced hepatic fibrosis. AIM and adipocytokines are possibly associated with pathological changes via a different mechanism.