If a parent or sibling has cirrhosis due to non-alcoholic fatty liver disease, a person's odds of having liver scarring are more than 12 times higher than for people without close relatives who have this condition, a small study finds.
Non-alcoholic fatty liver disease (NAFLD) is the build-up of extra fat in liver cells that is not caused by drinking alcohol.
The more severe form of NAFLD, non-alcoholic steatohepatitis (NASH), tends to develop in people who are overweight or obese or who have diabetes, high cholesterol or high triglycerides, according to the American Liver Foundation.
With NAFLD, the liver may swell and develop scarring, known as fibrosis, or cirrhosis in its more advanced stages. NASH often leads to more serious liver diseases, including liver cancer. About a quarter of people with NASH have cirrhosis.
Past research has suggested that NAFLD can run in families, but it wasn’t known if family members are also prone to developing fibrosis and more serious liver diseases.
“My goal is to change practice to develop screening guidelines for who are the patients who are at high risk for developing cirrhosis and should we be screening them,” said senior study author Dr. Rohit Loomba of the NAFLD Research Center at the University of California, San Diego in La Jolla.
One reason family members’ risk was poorly understood is that a diagnosis of fibrosis required a biopsy, which is a painful medical procedure. But Loomba and colleagues devised a way to detect fat and scarring in the liver using MRI scanning.
For the current study, Loomba and colleagues enrolled 26 patients with NAFLD and cirrhosis, along with 39 of their parents or siblings, as well as 69 people without liver disease plus 69 of their first-degree relatives.
The study team took medical histories, performed medical examinations and used MRI to evaluate the livers of all participants.
They found that three quarters of the relatives of patients with NAFLD and cirrhosis also had NAFLD.
Seven of these people, 18 percent of family members, also had advanced liver fibrosis, compared to 1.4 percent of the relatives of controls. The family members of NAFLD-cirrhosis patients were 12.5 times more likely to have liver fibrosis than the healthy comparison families.
“The data's very compelling. It reinforces smaller and less well-conducted studies that indicate a higher likelihood of non-alcoholic fatty liver disease fibrosis among family members,” said Dr. Scott Friedman, a liver disease specialist at Mount Sinai Hospital in New York who wasn’t involved in the study.
“So, it's important, because it may heighten our concern about the risk of undiagnosed liver disease in first-degree relatives of patients who've been diagnosed with NAFLD, particularly those who have more advanced fibrosis,” Friedman said in a phone interview.
There has been a rising awareness and incidence of liver disease associated with so-called metabolic syndrome, which is a constellation of abnormalities usually including obesity, insulin resistance, high blood pressure and high blood fats, Friedman noted.
“We're still trying to understand, certainly, what's the cause, what are the risk factors, who is at highest risk, how do we screen for those patients, and what do we do when we detect disease,” he said.
It’s important to note that aside from genetic contributions, first-degree relatives often share the same lifestyle habits, he added.
Currently, there are no proven therapies except diet and weight loss, which is hard to sustain. “But, there is an intense effort in the pharmaceutical and biotech industry to come up with new drugs to treat those conditions before it progresses to the cirrhotic state, where cancer and liver failure are real concerns,” Friedman said.
Loomba said new therapies are emerging. “There are about five Phase 3 trials for the treatment of NASH and especially advanced fibrosis in NASH.”
Once a patient develops cirrhosis, there’s a risk of developing liver cancer and those individuals need to be screened for that, Loomba added.
“We have a series of tests that need to be done on those individuals. And then, if the patient is obese for example and if they lose weight then you can even reverse fibrosis or progression of the disease.”