Non-alcoholic fatty liver disease (NAFLD) affects 10 percent of American adolescents and is on the rise among this group, according to a study funded by the National Institutes of Health (NIH), presented at the annual Digestive Disease Week conference and reported by the Emory University News Center.
NAFLD, a syndrome characterized by deposits of fat in the liver whose origin can’t be traced to alcohol consumption, can lead to diabetes and cardiovascular disease. Previous studies show that adolescents with NAFLD are at higher risk of cardiovascular disease in adulthood. In the worst cases, it can result in cirrhosis, a scarring of the liver. People with NAFLD often don’t exhibit any symptoms.
Researchers reviewed 1998-2008 data from the National Health and Nutrition Examination Survey, covering more than 10,000 U.S. adolescents ages 12 to 18.Participants were defined as having NAFLD if they were overweight or obese and if blood tests showed elevated levels of alanine aminotransferase (ALT), an enzyme associated with liver damage.
The study revealed that prevalence of NAFLD climbed from 3.3 percent in 1998 to 9.9 percent in 2008, increasing faster than the prevalence of childhood obesity. Researchers also found that NAFLD risk increased with participants’ waist size.
“We know that if a child is overweight, they are more likely to be overweight as an adult,” said lead researcher Miriam Vos, MD, MSPH, assistant professor of pediatrics at Emory University School of Medicine and a pediatric hepatologist at Children’s Healthcare of Atlanta. “We know from national data that teens with fatty liver disease become adults with fatty liver disease, unless they improve their diet and lose a significant amount of weight.”
The NASH Clinical Research Network, also sponsored by the NIH, has scheduled a new clinical trial for this summer to investigate treatment for NAFLD.