慢性C 型肝炎已是全球和台灣重要的健康衛生問題，除了肝硬化以及肝癌，肝外的併發 症也是臨床照護的重點，包括：混合型冷球蛋白症，慢性腎臟病，淋巴瘤，扁平苔蘚，修格 蘭氏症候群，紫質症，發炎性關節炎，憂鬱症，心臟血管疾病，中風以及第2 型糖尿病。慢 性C 肝病人合併第2 型糖尿病會增加慢性C 肝病人的疾病嚴重性。干擾素治療對於慢性C 肝 病人雖然有可能會引起短期內胰島素阻抗，但經過許多研究顯示，追蹤6-24 個月後會發現 接受干擾素治療達到SVR (sustained virologic response，持續病毒反應) 的組別，胰島素阻抗 相較治療前會有意義的下降，但NSVR 組別(non-sustained virologic response，非持續病毒反 應組別) 干擾素治療前後胰島素阻抗卻沒有意義的改變。除此之外，干擾素治療前血糖正常 的慢性C 型肝炎病人，SVR 組別長期追蹤2-8 年血糖異常或是第2 型糖尿病的發生率，相較 NSVR 組別，會有意義的下降0.37~0.48 倍。慢性C 型肝炎病人接受干擾素治療達到SVR， 似乎可以降低第2 型糖尿病的發生機會。

Chronic hepatitis C is a global healthy issue. Beside the liver cirrhosis and hepatocellular carcinoma, chronic hepatitis C may lead to several extra-hepatic manifestations including mixed cryoglobulinemia, chronic kidney disease, end-stage renal disease, lymphoma, lichen planus, Sogren’s syndrome, depression and type 2 diabetes mellitus. Chronic hepatitis C with type 2 diabets mellitus would increase the rate of decompensated liver cirrhosis, ascites, spontaneous bacterial peritonitis, renal dysfunction, hepatocellular carcinoma, hepatic encephalopathy, portal hypertension and esophageal varices bleeding. Interferon based therapy is the commonest treatment for hepatitis C among many countries. Although interferon based therapy may induce rapidly insulin resistance by counter- regulatory hormones increasing, patients with sustained virologic respond (SVR) among HCV-infected patients with interferon were noted with lower insulin resistance compared to baseline and the reduction of type 2 diabetes mellitus risk compared to non-sustained virologic responders. HCV-infected patients with interferon based therapy with SVR may reduce the risk of type 2 diabetes mellitus.