Nonalcoholic fatty liver disease: New epidemic

The global obesity epidemic has dramatically increased the prevalence of nonalcoholic fatty liver disease (NAFLD), such that it is the most common cause of chronic liver disease in Western nations. NAFLD is an important cause of liver disease in India also. The prevalence of NAFLD in India is around 9%-32% of general population with higher prevalence in those with overweight or obesity and those with diabetes or prediabetes. NAFLD is an important cause of unexplained rise in hepatic transaminases, cirrhosis, and hepatocellular carcinoma. The spectrum of abnormalities which the term NAFLD encompasses is isolated fatty liver, nonalcoholic steatohepatitis (NASH), and cirrhosis. The pathogenesis of NAFLD/NASH is complex and includes the development of insulin resistance, accumulation of excess lipids in the liver, mitochondrial dysfunction, and cell damage, and development of necroinflammation. Diagnosis is usually incidental during the evaluation for unrelated abdominal symptoms, elevated transaminases without any other explanation. Imaging modalities such as ultrasound are useful to diagnose the presence of excessive fat deposition in the liver but are not useful in differentiating simple steatosis from NASH. Liver biopsy may be useful in making this distinction, especially in those with risk factors for significant liver disease. Treatment modalities include weight reduction and exercise, metformin, Vitamin E, pentoxifylline, and saroglitazar and are effective in normalizing transaminases or in improving hepatic steatosis and inflammation in Indian patients with NAFLD. Randomized controlled treatment trials involving large number of patients with histological end point are required to assess the efficacy of different modalities