(Focus - Singapore)
A thorough professional, always willing to share his experiences - Dr. Chen Kok Pun connected with our team and discussed Liver Cirrhosis in detail.
Dr. Chen Kok Pun is a Gastroenterologist, presently serving at Tan Tock Seng Hospital.
The common causes of chronic liver injury other than the ingestion of toxins such as alcohol include chronic viral infections such as Hepatitis B, and C, as well as fatty liver disease.
We understand that the liver is the only regenerating organ in the human body, but at the same time in liver cirrhosis, it gets scarred and permanently damaged. Could you throw some light on the pathophysiology of liver cirrhosis to explain this?
Dr. Chen: Sure, I can give you an overview of liver cirrhosis. Liver diseases can be broadly categorized as ‘acute’ and ‘chronic’. Liver cirrhosis is the final pathway for many of these chronic liver diseases. It can be defined as scarring of the liver, which includes the replacement of normal liver architecture with liver nodules.
The rate of progression of chronic liver disease to cirrhosis can be variable. For example, in patients with biliary obstruction, it can progress to liver cirrhosis in a matter of weeks, compared to patients with hepatitis C infection, in whom progression can last up to decades before liver cirrhosis is diagnosed.
As far as the question about the pathophysiology is concerned, it is like the formation of scar tissue. Chronic injury to the liver cells, e.g., epithelial cells and stellate cells, can form scar tissue. In the initial stages, if the cause of the injury is removed, the scarring of the liver can be reversed. But, if the cause of the liver injury is not treated or addressed, then over time it can lead to liver cirrhosis to a point where the damage is irreversible.
What are the common causes that can lead to liver cirrhosis besides excessive alcohol intake?
Dr. Chen: The common causes of chronic liver injury other than the ingestion of toxins, such as alcohol, include chronic viral infections such as Hepatitis B and C, as well as fatty liver disease. The other less common causes include autoimmune liver disease and inherited liver diseases.
Is there any genetic component involved?
Dr. Chen: There are not many genetic components involved. Of course, there are some hereditary liver diseases as like Wilson's disease and hemochromatosis.
Are there any lifestyle habits that can lead to liver cirrhosis?
Dr. Chen: There are two major reasons – the main reason is chronic alcohol use, and number two would be fatty liver. Now, fatty liver is associated with metabolic diseases. Thus, patients who have concurrent comorbidities such as diabetes, hypertension, dyslipidemia, and obesity, basically, diseases commonly associated with lifestyle habits, are at risk of chronic liver disease, which may eventually lead to liver cirrhosis, if left untreated.
Are there any specific population who are at a higher risk of developing liver cirrhosis?
Dr. Chen: The population at higher risk of developing liver cirrhosis are those who have one or more of the causes of chronic liver injury as we discussed earlier like those who have chronic hepatitis B or C infection that are left untreated, those who have excessive alcohol intake, those who have fatty liver disease, people with known autoimmune liver diseases, or those with other rare inherited liver diseases. These people who have any of these, solo or in combination, are at a higher risk of developing liver cirrhosis.
Do you see any shift in the younger population as being observed with other diseases like diabetes, hypertension?
Dr. Chen: What we note in countries that follow a certain diet and are advanced in terms of their economic status is that they tend to consume more processed food, have higher sugar intake, tend to be more sedentary. These factors have been shown to increase the incidence of diabetes and obesity in these countries, and a parallel increase in the cases of fatty liver disease as well, which may lead to liver cirrhosis if left untreated.
Lifestyle modification like a healthy low salt diet, reduced alcohol consumption would definitely help. With a healthy low salt diet, you can reduce the risk and actually help to manage ascites efficiently.
As per literature, 30 percent of global liver cirrhosis causes can be attributed to Hepatitis B infection. Do you think hepatitis B vaccination can reduce the burden of liver cirrhosis?
Dr. Chen: The current estimates are that there are 2 billion people worldwide who have been infected with hepatitis B, and out of these 2 billion, around 250 million of them are chronically infected with hepatitis B. From these 250 million people who have chronic hepatitis B, the estimates are that 15 to 25% of them will die with liver cirrhosis or liver cancer.
It has been quite an effort by WHO in introducing the hepatitis B vaccine. And what we know is that in at least 180 countries the hepatitis B vaccine has been introduced. The hepatitis B vaccine has been proven to be safe and effective with protection estimated to persist for at least 30 years, greater than 90% of the persons are vaccinated. So, definitely, these levels of efficacy and long-lasting protection would really help in reducing the burden of liver cirrhosis.
What is the usual prognosis for a patient diagnosed with liver cirrhosis?
Dr. Chen: For prognosis, liver cirrhosis can be broadly categorized into two states, number one, when the liver cirrhosis is compensated and number two, when the liver cirrhosis is decompensated.
What we found is that compared with the general population, or people without liver cirrhosis, patients with compensated liver cirrhosis have a five-fold increased risk of death, whereas patients with decompensated cirrhosis, there is a ten-fold increased risk of death. The patients with compensated liver cirrhosis, have a median survival of about 9 to 12 years, and those who have shown signs of decompensated liver cirrhosis, have a median survival of about 2 years.
It not only depends on the clinical stage of the disease but also the presence of comorbidities. Patients with diabetes, heart disease, and stroke show a worse prognosis.
So, doctor to what extent does lifestyle modification impact prognosis?
Dr. Chen: Lifestyle modification like a healthy low salt diet, reduced alcohol consumption would definitely help. With a healthy low salt diet, you can reduce the risk and actually help to manage ascites efficiently. Actually, with the onset of ascites, the prognosis of liver cirrhosis decreases. When we talk about alcohol use, we should remember that alcohol is a toxin in unhealthy quantities. In lifestyle modification, if a person can reduce the ingestion of alcohol, then it will definitely help to improve the prognosis of patients with liver cirrhosis.
Are there any latest developments regarding diagnosis, treatment, and management of liver cirrhosis?
Dr. Chen: Talking about diagnosis, there are non-invasive methods available to detect the early stages of liver fibrosis, which is a stage before liver cirrhosis. These non-invasive methods include technologies such as liver elastography, or liver transient elastography. We have also developed calculators to use the biochemical test results for detecting liver fibrosis. Thus, with these tools, we can attempt to prevent the liver from reaching the irreversible or cirrhosis stage.
And then as for treatment, there are now effective cures for hepatitis C. So, hepatitis C is now curable, and the patient has to take these oral medications for only around eight to twelve weeks. This will definitely help to reduce the burden of liver cirrhosis that is caused by Hepatitis C.
For hepatitis B, there is no cure yet, but there are medications with high efficacy that help in suppressing the virus and now there are new medications available that have fewer side effects compared to medications used years ago. So, those are the latest developments in terms of diagnosis and treatment.
Thank you so much for taking part in our small discussion and providing your insights on this important disease. We are sure that our readers would find this interview helpful in understanding the disease better.