Written by David Bernstein, MD, FACP, FACG Friday, 27 November 2009 10:51
Fatty liver continues to be the most prevalent liver disease in America. While affecting more than 50 million Americans, most with this condition will have a benign course and will not develop significant liver disease. A small percentage, however, will develop inflammation and scarring in the liver in addition to just fat deposition. When these findings are present, they are indicative of more advanced liver disease and the condition is called non-alcoholic steatohepatitis or NASH. NASH can lead to cirrhosis and its complications including liver cancer and in certain circumstances, a liver transplantation may be needed. As Americans grow larger and this condition increases in prevalence, we can expect to see significantly greater morbidity and mortality from this condition. Current estimates are that 2-4 percent of people with fatty liver will develop NASH. This means that one to two million Americans are at risk for developing cirrhosis and its complications from this condition.
How non-alcoholic fatty liver develops remains unclear. We do know that alcohol use leads to fat within the liver which can progress to cirrhosis. In non-drinkers, the mechanism is uncertain. Some theories revolve around insulin resistance however many non-insulin resistant people develop NASH. The leading predisposing factors to the development of NASH appear to be diabetes and obesity. People with these conditions and abnormal liver tests are more likely to progress to more advanced disease.
The real question that needs to be answered is how best to treat NASH. The most commonly prescribed therapy for NASH is diet, exercise and weight loss. Although this regimen makes overall good sense, studies have not shown that mild weight loss alone changes the course of fatty liver. Bariatric surgery with significant weight loss has been shown to lessen fat within the liver and even reverse cirrhosis in some cases. Many people with fatty livers are placed on ursodeoxycholic acid to normalize the liver enzymes. Although this therapy is widely used, the jury is still out regarding its effectiveness. Many clinical trials with a handful of patients have not shown promise with medications such as clofibrate (a lipid lowering agent), and metformin and the thiazolidinediones (diabetes medicines) for the treatment of NASH. Vitamin E has been used in the treatment of NASH with some studies showing a small improvement in the amount of fat present. A recent study presented at the meetings of the American Association for the study of Liver Diseases in November 2009 showed that daily vitamin E use at a dose of 800 mg a day for one year in non-diabetic patients with NASH resulted in less fat cells within the liver than comparator arms with pioglitazone or placebo. There was no improvement in scarring at the end of the year with vitamin E use.
The prevalence of NASH is increasing and unfortunately so will its complications. The only way to stop this epidemic is to watch what we eat and hopefully not develop diabetes or obesity. If NASH occurs, diet and exercise remains the mainstay of therapy. In the non-diabetic patient with NASH, it seems reasonable to start vitamin E.
(Disclaimer: The views and opinions represented are those of the author and meant for informative purposes only. For your specific questions, consult your physician.)