Bariatric surgery reduces fatty liver disease risks, according to a Cleveland Clinic research study
About one-third of Americans are considered obese, and experts say health conditions caused by obesity, such as fatty liver disease, are rising at an alarming rate.
But, there is insufficient research about therapies for this disease and no drugs federally approved to treat it.
A new Cleveland Clinic study has found one treatment to be highly effective: bariatric weight loss surgery.
“The question that was addressed … is, if you reverse the obesity, can you reverse the liver disease? And the answer is surprisingly strong,” said Dr. Steven Nissen, principal investigator of the study and chief academic officer of the Clinic’s Heart, Vascular and Thoracic Institute.
A quarter of Americans have fatty liver disease, which, if it progresses, can cause serious health issues like liver cancer, cirrhosis and even death, Nissen said. In many cases, patients may need a liver transplant to survive, he said.
In the study published in the peer-reviewed journal JAMA Thursday, researchers found bariatric surgery significantly reduced the risk of these severe liver-related complications, as well as heart issues, in hundreds of Cleveland Clinic patients with advanced fatty liver disease.
Receiving the weight loss surgery was associated with an 88% lower risk of the disease progressing to severe liver outcomes, Nissen said. It also lowered the risk of heart complications such as heart attack and stroke by 70%, he added.
“I have been doing clinical trials for three or four decades. This is perhaps the most incredibly effective treatment I’ve ever seen for any disease,” Nissen said.
Experts have theorized for years that weight loss can significantly reduce the risk of fatty liver disease progression, but this is the first published study to demonstrate this, said Dr. Ali Aminian, the study’s lead investigator and director of the Clinic’s Bariatric & Metabolic Institute.
“Obesity is the main driver of fatty liver disease, and this study shows that if we can control obesity, we can control the consequences and decrease the risk of complications of fatty liver disease,” Aminian said.
The researchers looked at the outcomes of more than 1,150 Cleveland Clinic patients who had been diagnosed with a form of advanced fatty liver disease called nonalcoholic steatohepatitis, known as NASH, between 2004 and 2016. They followed the patients through March of 2021.
A group of 650 patients had received bariatric surgery during that time frame while a control group of 508 patients did not, Nissen said.
The study showed that 10 years after enrollment, advanced liver complications - such as cancer, cirrhosis, need for a transplant or death - occurred in 9.6% of the patients who did not receive bariatric surgery, compared to just 2.3% in the group that did.
“One group gets bariatric surgery and their NASH basically goes away, the other group doesn’t get bariatric surgery and they progress on,” Nissen said. “It wasn’t uncommon for people that continued with their obesity to go on and develop advanced liver disease.”
Additionally, 15.7% in the nonsurgical group had developed major cardiovascular complications such as heart attack and stroke, compared to 8.5% in the surgical group, Nissen added.
Another finding was that over a ten-year period, body weight was reduced by 22.4% in the bariatric surgery group compared to 4.6% in the nonsurgical group, he said.
The study looked at weight loss obtained by bariatric surgery, but the researchers think other weight loss methods will also reverse or reduce the risk of advanced liver disease, Aminian added.
“I hope that that can inform patients and physicians about the health benefits of weight loss, and if we can help patients lose weight, a large amount of weight, and help patients to keep the weight off for a long period of time, I think we can decrease the health consequences of this metabolic disease, which is pretty common in our society,” Aminian said.
Aminian added that more insurance companies are covering bariatric surgery nowadays, as research has come out showing the health benefits, but there are still some financial barriers. The safety of the surgery is also improving – about 3 to 5 percent of people experience complications after the surgery and 1 in 1,000 patients die, he said.
In the Clinic study, four out of the 650 patients who underwent surgery died due to complications, he added. The deaths occurred between 2004 and 2008, he said.
Aminian hopes down the line, more drugs and therapies that are less invasive than bariatric surgery will be studied and authorized.
There are some promising drugs coming down the pipeline, Nissen added.
“Bariatric surgery is a very good treatment. It probably should be done more frequently until we can get better drugs,” Nissen said.
In the meantime, the researchers hope the study will improve medical care for patients who have fatty liver disease and are obese.
“What we’re trying to do in educating people about this and developing better treatments is help people for the long haul,” Nissen said. “We’re not going to make good things happen in a year or two, but if you can lose weight and keep it off, the liver does not advance to cirrhosis and you don’t, as often, develop heart disease. Big benefits to weight loss.”