非酒精性脂肪肝病與非酒精性脂肪肝炎之診斷與流行病學

Diagnosis and Epidemiology of Non-Alcoholic Fatty Liver Disease and Non-Alcoholic Steatohepatitis

代謝症候群（metabolic syndrome, MetS）逐漸受到重視，其重要性在於一般人口中極為盛行，並且會引發全身各器官疾患，包括在肝臟表現的非酒精性脂肪肝病（non-alcoholic fatty liver disease, NAFLD）以及非酒精性脂肪肝炎（non-alcoholic steatohepatitis, NASH）。非酒精性脂肪肝病廣義地涵蓋了病理學上單純脂肪浸潤（steatosis）、非酒精性脂性肝炎、纖維化（fibrosis）甚至於肝硬化（cirrhosis）等不同嚴重程度的肝傷害，臨床上卻無喝酒過量的病史。在台灣，隨著經濟的發展，以及飲食習慣的西化，肥胖、糖尿病以及高血脂症的人口越來越多，代謝症候群以及非酒精性脂肪肝病已經大家相當重視的問題。脂肪肝意指「肝內的脂肪（主要是三酸甘油酯）含量超過全肝重量的5%」。診斷非酒精性脂性肝炎最基本的條件包括脂肪浸潤（steatosis），肝細胞膨脹（ballooning）和肝小葉發炎（lobular inflammation）。亞太地區非酒精性脂肪肝病相當常見。最近大型回顧文章指出，一般人口非酒精性脂肪肝病的盛行率在12-40%之間，在台灣，社區成人族群以及接受健康檢查的一般民眾中，脂肪肝病的盛行率在12-37%之間。亞太地區B型與C型肝炎盛行，同時合併代謝症候群與脂肪肝患者不在少數。最近回顧文章指出，B型肝炎族群非酒精性脂肪肝病的盛行率在15-50%之間。本綜論將針對非酒精性脂肪肝病的診斷與流行病學加以闡述。

Metabolic Syndrome (MetS) is prevalent in the general population and can cause diseases of various organs, including Non-Alcoholic Fatty Liver Disease (NAFLD) and non-alcoholic steatohepatitis (Non-Alcoholic SteatoHepatitis, NASH). Non-alcoholic fatty liver disease pathologically covers simple steatosis, NASH, fibrosis and even cirrhosis; but no clinical history of excessive drinking. In Taiwan, with the westernization of eating habits, the population of obesity, diabetes and hyperlipidemia is increasing. Fatty liver means “the content of fat (mainly triglycerides) in the liver exceeds 5% of the whole liver weight”. Essential criteria for the diagnosis of NASH include fatty infiltration (steatosis), hepatocyte swelling (ballooning) and lobular inflammation. NAFLD is fairly common in Asia Pacific. A recent large review article pointed out that the prevalence of NAFLD in the general population is between 12 and 40%. In Taiwan, the prevalence of fatty liver disease is between 12% and 37% among community adults and the general population undergoing health checks. Hepatitis B and C are prevalent in the Asia-Pacific region, and there are many patients with metabolic syndrome and fatty liver. A recent review article pointed out that the prevalence of nonalcoholic fatty liver disease in the hepatitis B population ranges from 15 to 50%. This review will address the diagnosis and epidemiology of nonalcoholic fatty liver disease.