A procedure known as gastric bypass surgery may significantly improve the prognosis of people with an aggressive form of non-alcoholic fatty liver disease (NAFLD) known as non-alcoholic steatohepatitis (NASH). So says a study released at the American Society for Bariatric Surgery Annual Meeting in Orlando, Florida earlier this month.¹

Liver-Damaging Condition
NASH is an inflammatory condition of the liver. If it occurs, it happens after fatty liver disease has developed. It differs primarily from NAFLD in that inflammation causes damage to the liver's cells, while simple fatty liver likely does not, experts say.

There is no specific cause of NASH; however, people who are obese and who may or may not have type 2 diabetes may be predisposed to this condition. There currently is no specific therapy for the disease. But patients who are obese, diabetic and have high lipids (fats) in their blood are advised to lose weight and control their diabetes and blood lipids via a low fat diet. People with NASH are also urged to avoid alcohol or other substances that could be harmful to the liver.²

Does Surgery Help?
In the new study, researchers at the University of Alabama at Birmingham wanted to find out if gastric bypass surgery might be helpful for these patients. Ronald Clements, MD, an associate professor of Surgery, and his associates retrospectively reviewed the records of 29 people (average age, about 42 years) who had undergone a routine liver biopsy during laparoscopic Roux-en-Y gastric bypass surgery, as well as a second biopsy during the same procedure about 17 months later, on average.

Roux-en-Y gastric bypass surgery is considered the "gold standard" procedure among weight loss surgeries. It's also the most frequent surgery of its type in the United States. Not only does the procedure help obese people lose weight and keep most of it off, experts say, but associated conditions like hypertension, diabetes, and depression are often improved or resolved.

Laparoscopic Roux-en-Y gastric bypass involves dividing the stomach and forming a small pouch while sealing off a large proportion of the stomach. This limits daily calorie intake to a maximum of about 1,000, say experts. A portion of the small intestine is then divided and attached to the small stomach pouch, which limits the body's ability to absorb calories.³ This type of procedure can be performed laparoscopically—a minimally invasive surgery in which tiny incisions are made and slender, telescope-like instruments are inserted. The procedure is then performed while viewing a television monitor.³

Gastric bypass can also be performed as open surgery.³

Liver Function Showed Improvement
The patients in the study had lost an average of about 117 pounds and had significant decreases in body mass index (BMI)—a measurement of healthy weight corresponding to height—by their second biopsy compared to their weight and BMI at the start of the study, Clements and his team reported.

Biopsies were tested for steatosis (fatty liver), steatohepatitis, portal fibrosis, and perisinusoidal fibrosis. A range of scores was then used in association with each condition.

On average, Clements and his fellow researchers noted that all aspects of liver health, except for portal fibrosis, significantly improved after gastric bypass surgery compared to the start of the study. Steatosis improved about 80%, there was a 100% improvement in steatohepatitis, and perisinusoidal fibrosis improved by about 23%, the research team wrote.

Twelve patients had features of NASH before surgery versus seven afterwards, the study team noted.

In nearly all patients, fat disappeared and liver inflammation was significantly reduced, Clements said. While portal fibrosis did not improve, that was mostly expected, he added. While previous scar formation is likely permanent, the surgery did remove the causes of the fibrosis formation, he stated.

There was no strict relationship between liver enzyme levels and the extent of liver damage at the start of the study, the investigators found, but alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels decreased significantly from the beginning of the study. Liver enzymes are chemicals released by the liver into the bloodstream when it is damaged. Doctors use levels of these enzymes as indicators of liver disease.⁴

Liver function showed some improvement after the gastric bypass procedure, Clements said, although noting that it was still within the normal range before surgery.

Since NASH is a disease that can be associated with obesity, routine liver biopsies should be performed in all patients who undergo gastric bypass, he added.

Does this mean surgery should be the option for all people with NASH? Not necessarily, experts say. It depends on many individual factors, and it's important to discuss this option with your physician.

John Martin is a long-time health journalist and an editor for Priority Healthcare. His credits include overseeing health news coverage for the website of Fox Television's The Health Network, and articles for the New York Post and other consumer and trade publications.