Alcohol still risk, but viral hepatitis, fatty liver disease main causes of cirrhosis - As the chief of the division of liver diseases at Mount Sinai, Scott Friedman is a hepatologist who does research on how scar tissue forms in the liver.
Who’s at risk
“Fibrosis” is a term doctors use to describe the scarring of the liver that builds up over time as the result of liver damage. “Over many years, that scarring progresses and culminates in cirrhosis, which refers to an end-stage fibrosis,” says Friedman. “By then, the blood flow through the liver is impaired, and liver function may be compromised.”
A healthy liver has many vital functions, like detoxifying the blood, synthesizing critical proteins and hormones, fighting off infection and metabolizing sugars, fats and proteins.
Advanced fibrosis and cirrhosis are major public-health concerns that dramatically increase your chance of developing liver cancer.
“Liver cancer is the fastest-rising cancer in the U.S. and the third-leading cause of cancer mortality worldwide,” says Friedman. “The bulk of patients with cirrhosis in this country have it from hepatitis B or C − about 5.3 million Americans are living with chronic viral hepatitis.”
The second-leading cause of fibrosis is called “fatty liver disease,” in which fat accumulates in the liver and eventually leads to scarring. “Obese patients often overlook the risk of liver damage,” says Friedman. “Obesity often goes hand in hand with metabolic syndrome, which is associated with elevated blood lipids and blood pressure, insulin resistance and pro-thrombotic and an inflammatory state.” Fatty liver disease often improves after weight-loss regimens like bariatric surgery.
The underlying cause for fibrosis can also be alcohol abuse or rarer conditions like autoimmune diseases of the liver. “Alcohol abuse is definitely a risk factor, but the vast majority of patients with fibrosis and cirrhosis don’t abuse alcohol,” says Friedman. The old association linking cirrhosis solely with alcohol abuse no longer holds true now that viral hepatitis and fatty liver disease are the two primary causes of fibrosis and cirrhosis.
Signs and symptoms
One of the challenges of diagnosing and treating liver disease is that it most often develops stealthily.
“The liver is so resilient that it can compensate for years of disease, and the patient may have no symptoms until the disease is very progressed,” says Friedman. “In reality, many patients have advanced fibrosis but have no symptoms.”
The very late manifestation of symptoms means that it is even more important to identify if people are at risk and screen them to catch the disease early.
“People at high risk of liver disease include Asian immigrants, who are more prone to hepatitis B, and patients with evidence of metabolic syndrome, who are at high risk of fatty liver disease,” says Friedman. Other risk factors for hepatitis include people who got blood transfusions before 1990 and people who engage in high-risk behavior like needle-sharing. Alcohol abuse is still a risk factor, even if it is no longer the most common underlying cause.
New evidence shows that simple blood tests can do an excellent job of identifying a patient’s risk of liver disease. “We screen for ALT − alanine aminotransferase − an enzyme that enters the bloodstream if the liver is damaged,” says Friedman. “An elevated ALT level without explanation merits followup.”
Traditional treatment
“We have no treatments approved to attack the scarring in the liver yet,” says Friedman. “But we have some excellent treatments for the underlying diseases.”
There are effective medical therapies for hepatitis B and C. “For hepatitis B, the main drugs are molecules that block the multiplication of the virus,” says Friedman. “The hepatitis C treatments are a combination of the drugs interferon and an immunomodulatory drug called ribavarin, which together boost the immune system to fight the virus.”
New drugs that attack the hepatitis C virus directly are expected to be available next year. For patients with fatty liver disease, weight-loss regimens also reduce liver damage. “Anything from diet and exercise and medications to bariatric surgery can have great results,” says Friedman.
If alcohol abuse is the underlying cause, patients are usually required to enroll in a 12-step rehab program.
Once the liver disease progresses to the point of impairing liver function, doctors treat the resulting symptoms. “We try to treat all the liver problems and screen for liver cancer,” says Friedman. “For select patients, liver transplantation may be necessary.”
But doctors hope they can help more patients control their liver damage before it gets to that point. “There is now evidence that if we treat the underlying liver disease, even cirrhosis is reversible,” says Friedman.
Doctors are making liver disease an increasingly manageable illness through prevention, early detection and the treatment of fibrosis before it progresses too far.
Research breakthroughs
Some of the most exciting liver disease research is being done at the molecular level.
In 1985, Friedman identified the cell type that’s responsible for the formation of scarring tissue.
“Basically, we’ve gone from uncovering [what] causes scar formation to soon being able to treat and prevent fibrosis with medication,” says Friedman. “Our hope is that if we develop new treatments for fibrosis, we’ll be able to prevent the development of cirrhosis.”
Questions for your doctor
Hepatitis is a major public health risk, so be proactive about asking your doctor, “Am I at risk of hepatitis?”
Follow up with, “Should I be vaccinated for hepatitis A and B?” Another good question is, “Do I have any risk factors for liver disease?” and “Is my ALT elevated?” ( nydailynews.com )
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