The theme for International Fatty Liver Day this year, an awareness initiative observed annually in June, is ‘Act Now, Screen Today’. This theme resonates more urgently today than ever before. Liver diseases were predominantly associated with excessive alcohol use and this remains an important cause of advanced chronic liver disease. However, in recent years, we are seeing the emergence of a silently growing threat to liver health — non-alcoholic fatty liver disease. As our understanding of this condition has evolved, we now know that fatty liver is closely linked to metabolic health, cardiac health, and a risk for developing cancers. This disorder has now been appropriately reclassified and is known as ‘Metabolic dysfunction-associated steatotic liver disease’ (MASLD). It has also resulted in a paradigm shift in how we approach liver health. The key is to screen, test, and treat.
Growing burden
The trends in fatty liver disease prevalence are alarming. MASH (Metabolic dysfunction-associated steatohepatitis), a progressive form that causes liver inflammation and scarring, is expected to become the most common cause of chronic liver disease and the leading indication for liver transplantation. The global prevalence of MASLD is estimated at 25-30%. In 2022, a meta-analysis revealed that in India, among adults, the pooled prevalence of fatty liver was 38.6%, while among obese children, it was around 36%.
There is a close link between fatty liver disease and metabolic syndrome, including obesity, diabetes, high blood pressure, and abnormal cholesterol levels. Individuals with these conditions have high MASLD prevalence rates: 55.5%-59.7% for diabetes, 64.6%-95% for obesity, and 73% for severe metabolic syndrome. Consuming excessive carbohydrates, especially refined carbs and sugars, worsens these conditions by causing metabolic problems. When the body has too much glucose, it increases insulin production to help cells absorb the glucose. However, constantly eating too many carbs causes persistently high insulin levels, leading to insulin resistance, where cells become less responsive to insulin.
Insulin resistance disrupts normal metabolism and promotes the conversion of excess glucose into fatty acids, which are then stored in the liver. The liver cells fill up with fat, leading to fatty liver. Over time, this continuous damage affects the liver’s ability to function properly, progressing from simple fatty liver to more severe conditions like such as steatohepatitis and cirrhosis, which are hallmarks of MASLD, and may require a liver transplant.
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Despite this growing burden of fatty liver disease, it often goes undetected as there is usually no warning or symptom in the early stages. Diagnosis is usually made at an advanced stage, often when significant liver damage has already occurred. The key to early diagnosis is simple — a comprehensive health screening that includes a thorough history, physical examination, blood tests, and an ultrasound of the abdomen. Physical examination will include height, weight, body mass index (BMI), abdominal girth, and waist-to-hip ratio to assess visceral fat, which is an important marker of metabolic health. Blood tests to cover cardio-metabolic risk factors include a blood count, sugar profile, blood lipid profile, liver function tests, and kidney tests. In a cohort of 50,000 people screened at Apollo Hospitals, amongst the 33% that had fatty liver, as observed using an ultrasound of the abdomen, only one in 3 had elevated liver enzymes in their blood test. An ultrasound of the abdomen is an important test to screen for liver disease and an important first step to diagnose fatty liver. It is often missed or not included in many health checks, largely because of the limited availability of radiologists as well as stringent regulatory approvals.
Also read | Fatty liver disease increasingly becoming a reason for transplant
Advanced liver tests will include liver fibrosis assessment to look for liver scarring, most accurately done by using newer technologies such as vibration-controlled transient elastography. This is a simple non-invasive tool and it measures liver stiffness to assess early stages of liver fibrosis. It can also be used to regularly monitor the progression and responses to treatment. Together, these tools — ultrasound, comprehensive metabolic screening, and elastography — form an integrated approach to effectively detect and manage liver diseases at an early stage.
Personalisation is the key
The selection of screening tests and the frequency with which they are performed should be personalised. This decision should be based on factors including an individual’s risk factors such as family history, lifestyle, and pre-existing health conditions. Clinicians should not make generic assumptions given the patient’s age or physical markers alone as we are increasingly witnessing non-communicable diseases break traditional stereotypes and impact very diverse people, including children. Moreover, multiple factors affect liver health, necessitating integrated strategies that combine dietary modifications, regular physical activity, and effective weight management to mitigate liver disease risks.
The liver is a ‘silent organ’ that typically does not exhibit noticeable signs of damage until it reaches an advanced stage. It is important that we are aware of the impact our lifestyle choices make in the long run. We need to take active control of our health, be aware of what we consume, and go for frequent screenings because the groundwork for a happy life begins with good health.
Murugan N. is Senior Consultant Hepatologist, Apollo Hospitals, Chennai; Akash Roy is Senior Hepatologist, Apollo Hospitals, Kolkata
Published - June 13, 2024 02:08 am IST