Children who have an unhealthy lifestyle, such as eating a diet filled with fatty and sugary foods and being inactive, are more prone to getting a chronic liver disease called non-alcoholic fatty liver disease (NAFLD), which is caused by excessive fat accumulating in the liver.
Being overweight or obese can lead to insulin resistance, which in turn can cause other problems such as increased free fatty acid levels in the blood, elevated blood sugar levels, and increased fat storage in the liver. Essam Imseis, MD, associate professor in the Department of Pediatrics at McGovern Medical School at The University of Texas Health Science Center at Houston (UTHealth), says other risk factors for developing fatty liver include being pre-diabetic or diabetic, or having abnormal cholesterol profiles or high blood pressure.
People with a family history of fatty liver are also at risk for developing NAFLD. In fact, certain genes might place some people or groups at risk for it. However, testing for these genes is not recommended nor routinely done because a single genetic test wouldn’t be helpful. “Developing this disease is most likely the result of a complex interaction between a number of genes and the environment, similar to other conditions like diabetes and obesity,” says Imseis, who is a pediatric gastroenterology specialist at UT Physicians and the medical director for the pediatric liver transplant program at Children’s Memorial Hermann Hospital.
NAFLD can be subdivided into two conditions: non-alcoholic fatty liver (NAFL), in which there’s fat in the liver but no inflammation, and a more severe non-alcoholic steatohepatitis (NASH), in which there is both fat and inflammation in the liver that resembles alcoholic hepatitis.
NASH was first used to describe people who had fat deposits and inflammation detected on liver tissue, which appeared to be similar to the effects of alcohol-related liver disease, which is why “non-alcoholic” is included in the disease’s name.
A future leading cause for liver transplant?
NAFLD is a major public health problem. It’s the second most common cause of liver disease requiring a liver transplant, and it’s projected to be the leading cause of liver transplant in the future. As many as one-fourth of the world’s population may have fatty liver, and incidences are increasing.
“Rising obesity rates are partly to blame, but not completely, since lean patients can also have fatty liver disease,” Imseis says. “People with this disease are also at risk for a number of other problems, including Type 2 diabetes and heart disease.”
About one-third of obese children may have NAFLD. Hispanic individuals have a greater risk of developing fatty liver. White and Asian children also have high incidences, compared to African-American children.
An asymptomatic condition
When Imseis diagnosed a 9-year-old Houston boy, Christopher Garcia, with NAFLD, he didn’t have any symptoms. “This is fairly typical, as most children with fatty liver disease don’t have any symptoms,” he says. Occasionally, children may complain of vague symptoms, such as fatigue or abdominal pain. About one-third may have dark patches of skin appear around the neck, armpits, or groin called acanthosis nigricans. This might be a sign of insulin resistance or diabetes risk, and up to 50 percent of children with NAFLD may have an enlarged liver.
If NAFLD is suspected, a doctor may recommend obtaining routine liver function tests and an ultrasound in order to detect it. A liver biopsy can definitely determine NAFLD, which was used to confirm that Garcia had the disease. In some instances, a doctor may prescribe blood or other laboratory tests to rule out other rare conditions that may have similar laboratory results.
In 2017, the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition published new guidelines for NAFLD screening and clinical care. They state that by ages 9 to 11, or sometimes younger, kids with a body mass index above the 95th percentile or those above the 85th percentile with additional risk factors should be screened.
Treatment is aimed at reducing fat and inflammation in the liver and preventing further liver damage. “Treatment is also helpful in reducing the risk of other conditions that are often seen in individuals with fatty liver disease, such as Type 2 diabetes and heart disease,” Imseis says.
The U.S. Food and Drug Administration hasn’t approved any drug treatment for this condition in children. Doctors treat NAFLD through lifestyle modifications including improved diet and increased physical activity. “Although there aren’t any good studies that favor one diet over others for treatment, a number of dietary approaches can lead to improvement,” Imseis says. Successful strategies might include reducing calories and avoiding sugar-sweetened beverages, which was recently reiterated in a study published in JAMA.
At Children’s Memorial Hermann Hospital, doctors work with nutritionists to provide strategies that may help each individual child. For Garcia, this meant no longer eating junk food, and eating more lean proteins such as chicken and fish.
Abeldanos says at first, making dietary changes was difficult. “I encourage Christopher and talk to him about why changes are necessary,” she says. In two months, Garcia was able to lose five pounds.
Increasing physical activity and decreasing sedentary behavior may also help. Imseis advises exercising at least five times a week and limiting screen time to no more than two hours a day.
Although Garcia didn’t exercise before, Abeldanos says he now enjoys soccer and biking, and he wants to start karate classes. “I limit screen time to 30 minutes a day,” she says. “This motivates him to do other things. I take him to the park and play with him.”
Abeldanos says Garcia is happy with his results so far. “He wants to be more active, so he can get better,” she says.
Imseis says high-dose vitamin E supplements may also help, but the effects of kids taking them long-term is unknown. Some adult studies show possible increased risk of certain cancers and even death when taking vitamin E.
“Without treatment, people’s symptoms typically worsen,” he says.
NAFLD is a serious condition. Children who have it are at a higher risk of developing a number of life-threatening problems, such as cirrhosis of the liver, liver cancer, Type 2 diabetes, and heart disease, and may continue to have it as adults. Adults who had NAFLD as a child have an increased risk of medical issues and death, often due to heart disease, diabetes, cirrhosis, or liver cancer.
Imseis and his research team are currently studying a number of dietary approaches in fatty liver disease patients to see if they might help manage the condition. “Lifestyle interventions with improvement in diet and increased physical activity are helpful, but sometimes they are difficult for children and families to do,” he says. “We’re studying the role of a diet involving time-restricted feeding to see if this would be a useful diet for families who are unable to make major changes to the type of food they consume. In such a diet, we allow children greater flexibility to choose the foods they want, but restrict how many hours of the day they can consume them.”