October 7, 2010

The skinny on fatty liver: Weight and metabolic disorders put millions at risk

By Katie Charles
THE DAILY CHECKUP
Wednesday, October 6th 2010, 4:00 AM

Who's at risk

About 30% of Americans have fatty liver, a condition whose name says it all. "Fatty liver is a condition where there's excess fat accumulation in the liver," says Chang. "A subset of patients who have fat in their liver have fat plus additional damage, which we call nonalcoholic steatohepatitis (NASH)."

If left unmanaged, NASH can lead to cirrhosis, liver transplant or liver cancer. "A liver biopsy is the only way to tell whether someone with fatty liver has the more severe NASH, although sometimes we can make an estimation without having to perform a liver biopsy," says Chang.

Doctors estimate that 2% to 9% of Americans have NASH. "Fatty liver disease is now a common cause of liver abnormalities and the most common cause of abnormal liver tests in the United States," says Chang. "We're seeing more patients for transplant or cancer with the fatty liver disease as the underlying cause."

At this point, fatty liver disease is even more prevalent than hepatitis C, which affects 1.5% of the population.

The main risk factors for fatty liver are obesity and metabolic syndrome. "Fatty liver is the liver manifestation of metabolic syndrome," says Chang. "So it's associated with all the other features of metabolic syndrome: high blood pressure, diabetes, high cholesterol and an increased waistline."

A minority of patients with fatty liver don't have metabolic syndrome. "Some medications can cause fatty liver, and there are genetically inherited disorders of fat metabolism, including a rare condition called congenital lipodystrophy that can be associated with fatty liver," says Chang.

The cause of fatty liver disease is still unclear and is an area of active research. Fatty liver is a condition that increases with age, although young people and kids can be affected. "The prevalence increases with age for a few reasons," says Chang. "Some of it is weight gain over time, and some of it is that the longer you've had fat in the liver, the more years you've had to develop liver damage."

Signs and symptoms

Fatty liver is often a stealth disease. "The early signs and symptoms are often silent," says Chang.

"It's usually an incidental diagnosis picked up by having blood drawn as part of a routine check-up." Most primary-care physicians run liver tests as part of a yearly physical, but it's worth asking to make sure your doctor tests for fatty liver.

Liver damage only begins to show symptoms when it reaches the point of end-stage liver disease. "At this point, the patient progresses to cirrhosis, which can cause symptoms a patient could note on his own — things like fluid retention and jaundice," says Chang.

"Another big concern or end-stage complication is liver cancer," she says. As more patients develop fatty liver disease, doctors are seeing increased amounts of liver cancer that developed in the presence of fatty liver disease. "The goal is to prevent fatty liver from progressing to cirrhosis," says Chang. "Or better yet, preventing it in the first place."

Traditional treatment

The first step for patients diagnosed with fatty liver is to develop a plan with their primary care physician to address obesity and related issues like diabetes and cholesterol. "Losing weight and keeping diabetes under control can improve fatty liver or keep it from causing damage," says Chang.

"I advise patients to limit both saturated fat and high-fructose-containing food products like sodas, both of which are associated with obesity," she says.

About a third of patients who have fatty liver get better, one third stay the same and one third get worse. The focus is on prevention and containment, because doctors don't have many options for patients whose disease worsens to the point of nonalcoholic steatohepatitis (NASH).

"Right now we have no FDA-approved medications to treat NASH," says Chang. "While there has been research using diabetes drugs, weight-loss medications and cholesterol medications to treat NASH, there is not enough evidence at this time to show that these drugs can be used to treat NASH directly."

Patients whose disease continues to progress can develop cirrhosis, an outcome doctors work very hard to prevent. "Once there is cirrhosis in a patient with NASH, there aren't a lot of options to reverse the damage," says Chang.

"Short of a liver transplant, there isn't much we can do besides advise to lose weight and keep diabetes and cholesterol under control," she says. Even liver transplant isn't a perfect cure, because the disease can come back after a transplant.

Research breakthroughs

One recent study had promising results for using vitamin E to fight fatty liver. "Last year, a National Institutes of Health multi-site collaboration called the PIVENS trial published its findings that using vitamin E improved liver tests and reversed scarring in the livers of patients with NASH," says Chang. "We need more supporting studies, but it's worth asking your doctor if vitamin E could help."

Questions for your doctor

Because this disease is usually asymptomatic, it's all the more important for patients to ask, "Could I have fatty liver disease?"

If you've been diagnosed, then the question becomes, "What can I do to keep my fatty liver from progressing?"

Eating a healthy diet and exercising regularly can go a long way toward keep fatty liver disease under control.

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