Bariatric surgery may be effective treatment for non-alcoholic fatty liver disease

Bariatric surgery may be an effective treatment for non-alcoholic fatty liver disease (NAFLD), suggests a new study accepted for presentation at ENDO 2020, the Endocrine Society's annual meeting, and publication in the Journal of the Endocrine Society.

The study compared three types of bariatric, or weight loss, surgery: gastric sleeve, gastric band and gastric bypass. "We believe that gastric bypass may be the best surgical option in these patients," said lead researcher Marta Borges-Canha, Ph.D., of Centro Hospitalar Universitário de São João in Porto, Portugal.

NAFLD is a condition in which excess fat is stored in the liver. This buildup of fat is not caused by heavy alcohol use. NAFLD is one of the most common causes of liver disease in the United States. The condition usually doesn't cause symptoms and is most often found when blood tests indicate elevated liver enzymes.

NAFLD is more common in people who have certain conditions, including obesity and conditions that may be related to obesity, such as type 2 diabetes. Researchers have found NAFLD in 40% to 80% of people who have type 2 diabetes and in 30% to 90% of people who are obese.

When the fat builds up in the liver and causes inflammation and damage, it is known as non-alcoholic steatohepatitis (NASH), which can lead to scarring of the liver—a potentially life-threatening condition called cirrhosis.

"NAFLD is strongly associated with obesity, and the prevalence of both diseases is notably increasing," Borges-Canha said. "There is a concerning lack of effective treatment options for patients with NAFLD." No medicines have been approved to treat NAFLD. The current recommended treatment is weight loss, which can reduce fat in the liver, inflammation, and fibrosis, or scarring.

The new study evaluated the effects of bariatric surgery on liver function and indicators of liver inflammation and scarring. The researchers included 1,995 morbidly obese patients who underwent bariatric surgery between January 2010 and July 2018. Their average age was 43, and 85.8% were female. One year after surgery, the patients had a significant decrease in liver enzymes. Other indicators of fatty liver disease, including the Fatty Liver Index (FLI), markedly decreased after one year. FLI is an algorithm that predicts liver steatosis or fat deposition. It is based on waist circumference, body mass index and levels of triglyceride and an enzyme found in the liver called γ-glutamyltransferase.

Another measure of fatty liver disease, called the BARD score, also markedly decreased. The BARD score predicts liver scarring. It is calculated using the ratio of two liver enzymes, body mass index and the presence of diabetes.

Gastric sleeve was associated with a greater reduction of liver enzymes and both FLI and BARD compared with gastric band. However, gastric sleeve led to a smaller reduction of FLI and BARD compared with gastric bypass surgery.