Nonalcoholic fatty liver disease (NAFLD) has become the most common chronic liver disease affecting approximately 25% of the global population. Although a majority of NAFLD patients will never experience liver-related symptoms it is estimated that 5-10% will develop cirrhosis-related complications with risk of death or need for liver transplantation. NAFLD is closely associated with cardiovascular disease and components of the metabolic syndrome. However, NAFLD is not uncommon in lean individuals and may in these subjects represent a different entity with separate pathophysiological mechanisms involved implying a higher risk for development of end-stage liver disease. There is considerable fluctuation in the histopathological course of NAFLD that may partly be attributed to lifestyle factors and dietary composition. Nutrients such as fructose, monounsaturated fatty acids, and trans-fatty acids may aggravate NAFLD. Presence of type 2 diabetes mellitus seems to be the most important clinical predictor of liver-related morbidity and mortality in NAFLD. Apart from severity of the metabolic syndrome, genetic polymorphisms and environmental factors, such as moderate alcohol consumption, may explain the variation in histopathological and clinical outcome among NAFLD patients.

中文翻译：

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影响非酒精性脂肪肝疾病发展的既定因素和新兴因素。

非酒精性脂肪肝疾病（NAFLD）已成为影响约25％全球人口的最常见的慢性肝病。尽管大多数NAFLD患者从未经历过与肝有关的症状，但据估计有5-10％的人会发生与肝硬化有关的并发症，并有死亡或需要肝移植的风险。NAFLD与心血管疾病和代谢综合征的组成部分密切相关。然而，NAFLD在瘦的个体中并不罕见，并且可能在这些受试者中代表具有不同病理生理机制的不同实体，这暗示着罹患终末期肝病的风险更高。NAFLD的组织病理学过程存在相当大的波动，这可能部分归因于生活方式因素和饮食组成。营养物质，例如果糖，单不饱和脂肪酸和反式脂肪酸可能加重NAFLD。2型糖尿病的存在似乎是NAFLD中与肝有关的发病率和死亡率的最重要的临床预测指标。除了代谢综合征的严重程度外，遗传多态性和环境因素（例如适度饮酒）可能解释了NAFLD患者的组织病理学和临床结局的差异。