The Present Situation of Non-Alcoholic Fatty Liver Disease in the Asia-Pacific Region

Non-alcoholic fatty liver disease (NAFLD) is the most common liver disorder in Western industrialized countries, and now it is also becoming prevalent in developing countries, such as China. Professor Jiangao Fan, from Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China, presented a report on non-alcoholic fatty liver disease in the Asia-Pacific Region. He pointed out that based particularly on large community-based studies using ultrasonography, case-control series and prospective longitudinal studies, the prevalence of NAFLD in Asia was between 12% and 24%, depending on age, gender, locality and ethnicity. There is strong evidence that the prevalence of NAFLD has increased recently in parallel with regional trends in obesity, type 2 diabetes, and metabolic syndrome (MetS); and that further increases are likely. Moreover, NAFLD patients with normal body weight seem to more common in Asians than Caucasians. NAFLD appears to be associated with long-standing insulin resistance and likely represents the hepatic manifestation of MetS. Not surprisingly therefore, Asians with NAFLD are at high risk of developing diabetes and cardiovascular disease. The increasing prevalence of obesity, coupled with diabetes, dyslipidemia, hypertension and ultimately MetS puts more than half the world's population at risk of developing NAFLD in the coming decades. Therefore, NAFLD seems to be a major public health concern in the Asia-Pacific Region. In many countries where some estimation of NAFLD prevalence has been made, the magnitude of the problem is comparable to western countries.

Professor Fan said that NAFLD was also emerging into a new and major health problem in once lean Chinese, where traditionally clinicians have dealt with the formidable burden of chronic hepatitis B. Fatty liver is highly prevalent in China and is more often linked to obesity than to alcoholism. Among more affluent regions of China, the community prevalence of NAFLD is >15%. With the increasing pandemic of obesity, the prevalence of NAFLD has approximately doubled in the past decade. The full range of histological manifestations of NAFLD has been demonstrated in Chinese patients, but to date hepatic severity is generally mild. In contrast to chronic hepatitis C, steatosis is less common in patients with chronic hepatitis B infection; it is associated with metabolic factors not viral ones, and does not appear to affect disease severity of hepatitis B.