Metabolism associated fatty liver disease (NAFLD/MASLD)
Overview
Metabolism associated steatotic liver disease (MASLD) or Non-alcoholic Fatty Liver Disease (NAFLD), often called fatty liver disease, is a condition where there is too much fat in your liver. The important point is that this condition is not related to alcohol, which is often a false assumption when someone presents with liver problems. In MASLD, the abnormal accumulation of fat in the liver is closely linked with being overweight and exposure to processed foods, but also with genetics, and other conditions such as Type 2 Diabetes and diseases of the heart and blood vessels. In fact, MASLD/NAFLD is the most common long-lasting liver disease worldwide. Although MASLD/NAFLD can be a complex disease to treat the good news is that when caught early the condition can be fully reversed.
The names MASLD/NAFLD, Fatty Liver Disease, and NASH: What do they mean?
MASLD/NAFLD is found when there is an abnormal collection of fat in the liver without harmful alcohol intake; defined as more than 20g alcohol each day (1 pint of lager or 2 small glasses of wine) for women and more than 30g alcohol each day (1.5 pints of lager or 3 small glasses of wine) for men. When an individual reports harmful alcohol intake and has abnormal fat in their liver due to certain risk factors such as being overweight, the name metabolism and alcohol related liver disease, MetALD is the preferred name.
Metabolism associated steatohepatitis (MASH) is a more severe stage of MASLD which may develop over time whereby the liver has increased stiffness (fibrosis). When caught early liver damage can be reversed, however if left untreated there is an increased risk of progression of liver damage including the development of liver cirrhosis (irreversible liver stiffness), liver cancer, or liver failure.
What causes MASLD?
Some common causes of MASLD are:
• Being overweight or obese
• Increase fat around the waist
• Having Type 2 Diabetes
• A diet with processed foods and drinks
• Little physical activity each day
• High blood pressure
• High levels of cholesterol in the blood
• Genetic factors
How severe can MASLD get? (Stages of MASLD)
Stage 0: Fat in the liver
There is a build-up of abnormal fat in the liver, but the liver has not been damaged or scarred. At this stage, MASLD is fully reversible with healthy living.
Stage 1: MASH with mild fibrosis
Metabolism associated steatohepatitis (MASH) is a result of the fat in the liver causing inflammation and damage to your liver. At this stage the inflammation can cause an increase in stiffness (fibrosis) in the liver, however your liver is still functioning well. Healthy living can reverse the damage and any underlying MASLD.
Stage 2: MASH with moderate fibrosis
Inflammation and damage to your liver is increasing but your liver is still able to carry out its functions and you may not have any symptoms. There is an increased risk of further liver damage, however with proper management and a healthy lifestyle some of the damage can be repaired and in some cases the underlying MASLD can still be reversed at this stage.
Stage 3: MASH with advanced fibrosis
At this stage the liver has accumulated a lot of damage and a lot of scarring is present (advanced fibrosis). It is urgent to prevent and stop any further liver damage and scarring before it progresses to a permanent state of damage (liver cirrhosis). With proper management and a healthy lifestyle, some of the damage can be repaired and the liver may be able to perform all of its functions. At this stage your doctor may request to see you more frequently and perform certain tests to check the health of your liver and to screen for liver cancer.
Stage 4: Cirrhosis
When cirrhosis is present, the liver has so much scarring that the liver becomes nodular or “lumpy” and it changes the shape of the liver which can be seen on scans. The scarring is usually permanent, and the goal at this stage is to prevent liver failure and to preserve any remaining liver function. Cirrhosis increases your risk of liver cancer and there is a need to have dedicated screening for liver cancer with an ultrasound every 6 months. At this stage you should be under the care of a specialist with experience in caring for patients with liver cirrhosis.
Symptoms of MASLD
Most individuals with MASLD may not know that they have the condition as some individuals may not have any symptoms at all. However, some persons with MASLD may report symptoms of tiredness, fatigue, not feeling like themselves, or discomfort in the right side of their tummy where the liver is.
If you develop any of the following signs or symptoms you should seek medical help right away:
• Yellowing of the eyes and/ or skin (jaundice). Note, this may not always be easily seen with darker skin tones.
• Very dark urine
• Itchy skin all over
• Swelling in the tummy area (ascites) or in the legs.
• Vomiting blood or material that looks like coffee grounds
• Dark, black, or tarry coloured stool
• Confusion, brain fog, mood changes, poor memory or poor judgement (encephalopathy)
• Easy bruising of the skin
How is MASLD diagnosed?
MASLD is usually diagnosed using a range of tests including blood tests and scans. Your doctor may request these tests if they suspect you may have a problem with your liver, and sometimes MASLD might be picked up ‘by chance’ on tests which were done to investigate another health problem.
1. Questions related to your lifestyle
In order to diagnose MASLD, your doctor needs to ask about risk factors and other causes of liver disease. They will ask you about:
o Any other medical conditions you or your family may have
o The amount of alcohol you drink
o Your diet including foods, drinks, and your dietary patterns.
o How physically active you are, and how much exercise you do
o Any medications you may be taking including prescribed, over the counter, homeopathic, alternative supplements, or medications bought online.
o Use of recreational drugs
2. Blood tests
Liver blood tests check various substances related to liver damage and repair. In particular, a liver blood test called Alanine Aminotransferase (ALT) may be raised in persons with MASLD.
3. Scans
o Ultrasound: This is a scan similar to what is used to check on a baby in the womb during pregnancy. It is a painless scan, whereby the technician will place gel on your tummy and pass a probe over the gel. The machine uses sound waves to have a look at organs and structures in your abdomen and can detect fat in the liver by observing areas of brighter colour in the liver. It can also give useful information on the size and smoothness of the liver, as well as important structures around the liver.
o Transient elastography (e.g. FibroScan™): This scan is very similar to an ultrasound and uses vibration to send a pulse wave to your liver and back to the probe which can be felt as a gentle flick on your skin underneath the probe. This test can measure the degree of stiffness (fibrosis) in the liver as well as the amount of fat in the liver (steatosis) and it is a very useful test to determine the stage of liver diseases.
4. Liver Biopsy
Not everyone requires a liver biopsy if they have abnormal liver blood tests or scans. In some cases the amount of information available from blood tests and scans may not be enough to make a clear diagnosis. In these cases, your doctor might suggest getting a liver biopsy which can help with making a diagnosis as well as determining the stage of liver damage.
Liver biopsies are done in the hospital by a specialist (usually an Interventional Radiologist) and you usually do not have to stay overnight in the hospital after the procedure if there are no issues. You will have a local anaesthetic to the skin over the liver, and the specialist will use a thin needle to take a small sample from your liver (a biopsy). This biopsy sample is sent to a different specialist called a Pathologist who will examine the biopsy sample under a microscope to look for changes in the liver cells that can help make a diagnosis.
With every procedure there are risks, and some complications of liver biopsies include pain, bleeding, and infection. Your doctor will explain the risks and benefits of having a liver biopsy with you to help you make a decision about whether you agree (consent) to having it done. For more information on liver biopsies click here.
I’ve been diagnosed with MASLD, what does it mean for me?
If your tests show that you have MASLD, your family doctor will usually arrange any necessary tests and check-ups as MASLD can be associated with diseases of the heart and blood vessels. If you MASLD is advanced, or you have other complex medical conditions, your doctor may refer you to a hospital specialist to help with your care.
The main goals of management are:
1) To stop the condition getting any worse and to prevent complications such as liver cancer or liver failure
2) To repair as much damage to the liver as possible
How is MASLD treated?
1. Healthy Lifestyle
The main treatments for MASLD are eating a well-balanced diet, increasing physical activity each day, or exercising such as with long walks, jogging, cycling or swimming (aerobic exercises). In many cases losing weight is necessary, and studies have shown that losing weight around the tummy area has the best effect on reducing the amount of fat around organs and in the liver.
2. Medications
For people who have MASLD and Diabetes, there are certain medications that can help treat both your Diabetes and MASLD. You should talk to your doctor to find out if this is right for you.
The most common causes of death in people with MASLD are due to diseases of the heart and blood vessels (circulatory system). For this reason it is important that conditions such as high blood pressure, high cholesterol, or Type 2 Diabetes are well managed by your doctor.
3. Clinical Trials
One way that people with MASLD can help is by getting involved in Clinical Trials which study new treatment options for MASLD. For more information on Clinical Trials currently available speak to your specialist.
Who will oversee my medical care?
You will have the most important role in your management of MASLD as diet, increased physical activity, exercise, lifestyle improvements, and perseverance make all the difference in improving your liver’s health and preventing worsening of MASLD.
In early MASLD, your family doctor may be involved in routine health checks as well as performing blood tests to monitor your liver. As you may not experience any symptoms with early MASLD, your family doctor can ensure that you do no develop complications from MASLD, as well as request screening every 3 years for advanced liver fibrosis.
In later stages of MASLD, or if you have other related medical conditions such as Diabetes, hospital specialists may become involved in your care. It is important for you, your family doctor, and any specialists involved in your care to work together to manage your overall health.