Common GI Conditions

What is it?
NAFLD is characterised by excessive fat accumulation in liver cells (hepatic steatosis), in the absence of excess alcohol intake, or other causes of liver fat accumulation (such as certain liver diseases, systemic diseases, or medications).

The two subtypes of NAFLD are Non-Alcoholic Fatty Liver Disease (NAFLD) and Non-Alcoholic Steatohepatitis (NASH). The differences between the two are as follows:

• NAFL results in liver fat accumulation
• NASH results in liver fat accumulation as well as evidence of liver cell damage, such as inflammation (steatohepatitis) and/or scarring (fibrosis).

How common is it?

NAFLD is common, with a prevalence of 25-30% in Asia and Singapore.

What are the causes of NAFLD?
NAFLD is generally thought to be associated with metabolic stress in relation to caloric excess. Risks and contributors for developing NAFLD include

• Dietary factors, such as high-calorie intake, consumption of excessive refined carbohydrates, sugar and fructose
• Physical inactivity
• Obesity and the metabolic syndrome (diabetes mellitus, high cholesterol/triglycerides, high blood pressure)
• Certain genetic predispositions

What problems can it cause? 

In a proportion of patients, NAFLD can become NASH. Those with NASH subtype are more likely to accumulate liver damage over time, resulting in liver scarring – fibrosis and eventually cirrhosis – with the potential to develop liver failure and/or liver cancer.

Individuals with NAFLD are also at increased risk of cardiovascular complications such as heart attacks and strokes. This is the major cause of death in patients with NAFLD.

What tests will I need? 

Your doctor will request blood tests to assess the overall function of your liver, and whether there is any inflammation. He may also order tests to exclude other causes of chronic liver injury (e.g Hepatitis B, C, autoimmune hepatitis).

In the initial assessment, he may order an ultrasound to assess the structure of the liver.

An assessment of the extent of liver damage accumulated so far – in the form of scarring (fibrosis) – will also be performed. One common way to measure your liver stiffness is a special scan (elastography), but may also be estimated using a panel of blood tests, or when necessary, by a liver biopsy (using a needle to extract liver tissue for examination under a microscope).

An assessment of cardiovascular risk factors including blood sugar, cholesterol profile and blood pressure will also be checked, to evaluate and reduce the long-term risk of heart attacks and strokes.

What treatments or monitoring will I need? 

The mainstay of treatment for NAFL/NASH is dietary and lifestyle intervention to achieve weight loss.

Losing weight has been shown to reduce liver fat, liver cell injury, and prevent or improve liver scarring (fibrosis). One should aim to lose 7-10% of their body weight.

For individuals with concurrent diabetes, cholesterol or high blood pressure, the treatments of these conditions also need to be optimised.
With regards to medications directly treating NAFL/NASH, to date there is no approved medication with unequivocal long-term benefit, although much research is under way. Vitamin E is one of the medications that may be prescribed, however there are some potential risks with this. The decision to start Vitamin E should be done after a thorough discussion with your Doctor.

If significant liver scarring (fibrosis or cirrhosis) has developed, regular or additional monitoring will likely be necessary.

References
1 Younossi Z, Henry L. Contribution of Alcoholic and Nonalcoholic Fatty Liver Disease to the Burden of Liver-Related Morbidity and Mortality. Gastroenterology, Volume 150, Issue 8, June 2016, Pages 1778-1785