Current treatment strategies for non-alcoholic fatty liver disease (NAFLD)

Nonalcoholic fatty liver disease (NAFLD) is recognized as the most common cause of chronic liver disease worldwide. NAFLD is a clinicopathologic syndrome ranging from simple steatosis, which is relatively benign, to the more severe form known as nonalcoholic steatohepatitis (NASH), which may progress to cirrhosis, liver failure, and hepatocellular carcinoma. NAFLD is associated with significant liver related morbidity and mortality, and its underlying pathophysiology is thought to result from a multiple hit process. The initial insult is the accumulation of hepatic fat secondary to insulin resistance. In the setting of hepatic steatosis, the second hit can be caused by reactive oxygen species, inflammatory cytokines, and adipokines. Several therapeutic modalities that target these mechanisms are under investigation, but no proven treatment has yet emerged. Insulin sensitizers such as thiazolidinediones and metformin show promise, and several studies have explored the role of lipid lowering agents, antioxidants, and cytoprotective agents. Novel agents such as anti-obesity drugs, selective cannabinoid-1 receptor blockers, and dual PPAR alpha and gamma agonists are also under investigation. Unfortunately, data on the long-term safety and efficacy of these agents and their impact on liver related histologic outcomes are currently lacking. NAFLD treatment currently focuses on reducing metabolic risk factors, with the mainstay of therapy focusing on life-style modifications such as gradual weight loss through diet and regular exercise.