If detected and managed early, it’s completely possible to stop a fatty liver from progressing to more serious and even end-stage liver disease.
However, if left unchecked:
- Simple fatty liver (steatosis), where there’s fat build-up in the liver but no inflammation yet, can progress to a more serious, inflammatory form of non-alcoholic fatty liver disease (NAFLD) called non-alcoholic steatohepatitis (NASH).
- NASH may lead to fibrosis, where scar tissue forms as a result of ongoing inflammation, and cirrhosis, where there’s a great amount of scarring, inflammation and permanent liver damage.
- Cirrhosis can lead to liver cancer and life-threatening liver failure, where the only treatment option may be a liver transplant.
Liver fat also plays a role in the development and progression to type 2 diabetes and cardiovascular disease. Simple fatty liver is a strong predictor of an increased risk of heart attack, stroke and other vascular related problems, e.g. poor blood flow to the legs. Certain cancer risks are also increased in NAFLD, e.g. colon cancer.
It isn’t yet clear why some people with NAFLD progress to NASH, while others don’t. But it’s believed that insulin resistance may lead to fat build-up in the liver and that some types of oxidative stress (an imbalance between harmful free radicals and neutralisation by antioxidants) cause the disease to progress. Many factors – including drugs, environmental pollutants and irradiation – may lead to oxidative stress in the liver.
The prognosis of NAFLD depends on the stage of the disease. Simple fatty liver has a good prognosis, whereas 10-20% of people with NASH go on to develop cirrhosis within a period of eight years.
Reviewed by Dr Mark Sonderup, B Pharm, MB ChB, FCP (SA). Senior Specialist, Division of Hepatology, Department of Medicine, University of Cape Town and Groote Schuur Hospital. July 2018.