What is fatty liver?
Fatty liver is a condition where excess fat builds up in the liver. It is also known as hepatic steatosis. To define a fatty liver, there should be excess fat deposition in liver and there should not be a secondary cause of fat deposition like alcohol, certain medicines and certain hereditary disorders. It is commonly associated with diabetes mellitus, obesity and dyslipidemias like hypercholesterolemia and hypertriglyceridemia.
Non-Alcoholic Fatty Liver Disease (NAFLD) is a broad term, encompassing a spectrum of fatty liver disease from fatty liver to steatohepatitis to liver cirrhosis. It is categorized in NAFL (Non-Alcoholic Fatty Liver) and NASH (Non-Alcoholic Steatohepatitis). NAFL is a condition where there is 5% or more fat deposition in liver without liver cell injury. NASH is a condition, characterized by 5% or more fat deposition in liver with inflammation and liver cell injury with or without fibrosis.
Magnitude of the problem
The incidence of fatty liver disease is rising in the general population worldwide and it is now one of the commonest causes of liver cirrhosis. The prevalence of NAFLD in general population worldwide is estimated to be approx. 20-30%. The prevalence of NASH in general population is estimated to be approx. 1.5-6%. The increasing incidence of fatty liver disease is partly due to sedentary lifestyle, increasing prevalence of diabetes mellitus and unhealthy food habits. In fact, the prevalence of NAFLD and NASH in high-risk groups like people with obesity, diabetes mellitus and dyslipidemias is found to be very high.
What are the complications of fatty liver?
Fatty liver disease is a progressive disease if effective timely measures are not taken. With continuing injury to the liver, the NAFL stage progresses to NASH, which is characterized by continuous inflammation in liver. With time, progressive fibrosis sets in, and NASH progresses to cirrhosis of liver. A cirrhotic liver is a fertile ground for developing liver cancers (hepatocellular carcinoma). A peculiar thing about NAFLD is that liver cancers have been found to develop even in absence of cirrhosis in NAFLD.
How to diagnose fatty liver?
Fatty liver can be diagnosed on the basis of liver function test (blood investigations), abdominal ultrasound, fibroscan, MR Elastography (MRE) and CT scan for liver attenuation. Most of these patients, in the initial stage of their disease, may not have any symptoms. It is generally diagnosed on an abdominal ultrasound as a part of routine health check-up or for other indications and sometimes on mild derangement of liver function tests. Fibroscan and MRE are considered to be very accurate to confirm the diagnosis of fatty liver.
How to prevent and treat fatty liver?
Fatty liver can be prevented by lifestyle modifications. Keeping the weight controlled by active lifestyle and avoiding unhealthy and junk foods goes a long way in keeping the liver healthy. Adding regular physical exercise in daily routine also helps in a big way to avoid fat deposition in liver.
The treatment of fatty liver pivots on 3 things
1) Weight loss by diet control and physical exercise
2) Strict diabetes control in diabetic patients
3) Treatment of dyslipidemias like hypercholesterolemia and hypertriglyceridemia
Weight control is the key to treatment of fatty liver. Studies have found that higher the degree of weight loss, the better is the improvement in fatty liver. Even, 5-7% weight loss in a person causes marked improvement in fatty liver. Weight control can be achieved by diet control (restricting the calorie intake) and physical exercise in any form.
Strict diabetes control is very important in diabetic patients with NAFLD to prevent progression of the disease. Also, medical treatment of dyslipidemias is also imperative for control and reversal of NAFLD.
Once cirrhosis sets in, in NAFLD, the treatment is very much like other patients of liver cirrhosis and most of these patients will ultimately require a liver transplantation.
