– There is a long list of benefits from bariatric surgery in the morbidly obese, but prevention of end-stage liver disease and the need for a first or second liver transplant is likely to grow as an indication, according to an overview of weight loss surgery at Digestive Diseases: New Advances, held by Rutgers, the State University of New Jersey, and Global Academy for Medical Education.

“Bariatric surgery is associated with significant improvement not just in diabetes, dyslipidemia, hypertension, and other complications of metabolic disorders but for me more interestingly, it is effective for treating fatty liver disease where you can see a 90% improvement in steatosis,” reported Subhashini Ayloo, MD, chief of minimally invasive robotic hepato-pancreato-biliary surgery and liver transplantation at New Jersey Medical School, Newark.

Trained in both bariatric surgery and liver transplant, Dr. Ayloo predicts that these fields will become increasingly connected because of the obesity epidemic and the related rise in nonalcoholic fatty liver disease (NAFLD). Dr. Ayloo reported that bariatric surgery is already being used in her center to avoid a second liver transplant in obese patients who are unable to lose sufficient weight to prevent progressive NAFLD after a first transplant.

Nonalcoholic fatty liver disease Courtesy of Wikimedia / Nephron / Creative Commons License

The emphasis Dr. Ayloo placed on the role of bariatric surgery in preventing progression of NAFLD to nonalcoholic steatohepatitis and the inflammatory process that leads to fibrosis, cirrhosis, and liver decompensation, was drawn from her interest in these two fields. However, she did not ignore the potential of protection from obesity control for other diseases.

“Obesity adversely affects every organ in the body,” Dr. Ayloo pointed out. As a result of weight loss achieved with bariatric surgery, there is now a large body of evidence supporting broad benefits, not just those related to fat deposited in hepatocytes.

“We have a couple of decades of experience that has been published [with bariatric surgery], and this has shown that it maintains weight loss long term, it improves all the obesity-associated comorbidities, and it is cost effective,” Dr. Ayloo said. Now with long-term follow-up, “all of the studies are showing that bariatric surgery improves survival.”

Although most of the survival data have been generated by retrospective cohort studies, Dr. Ayloo cited nine sets of data showing odds ratios associating bariatric surgery with up to a 90% reduction in death over periods of up to 10 years of follow-up. In a summary slide presented by Dr. Ayloo, the estimated mortality benefit over 5 years was listed as 85%. The same summary slide listed large improvements in relevant measures of morbidity for more than 10 organ systems, such as improvement or resolution of dyslipidemia and hypertension in the circulatory system, improvement or resolution of asthma and other diseases affecting the respiratory system, and resolution or improvement of gastroesophageal reflux disease and other diseases affecting the gastrointestinal system.

Specific to the liver, these benefits included a nearly 40% reduction in liver inflammation and 20% reduction in fibrosis. According to Dr. Ayloo, who noted that NAFLD is expected to overtake hepatitis C virus as the No. 1 cause of liver transplant within the next 5 years, these data are important for drawing attention to bariatric surgery as a strategy to control liver disease. She suggested that there is a need to create a tighter link between efforts to treat morbid obesity and advanced liver disease.

“There is an established literature showing that if somebody is morbidly obese, the rate of liver transplant is lower than when compared to patients with normal weight,” Dr. Ayloo said. “There is a call out in the transplant community that we need to address this and we cannot just be throwing this under the table.”

Because of the strong relationship between obesity and NAFLD, a systematic approach is needed to consider liver disease in obese patients and obesity in patients with liver disease, she said. The close relationship is relevant when planning interventions for either. Liver disease should be assessed prior to bariatric surgery regardless of the indication and then monitored closely as part of postoperative care, she said.

Dr. Ayloo identified weight control as an essential part of posttransplant care to prevent hepatic fat deposition that threatens transplant-free survival.

Global Academy and this news organization are owned by the same company. Dr. Ayloo reports no relevant financial relationships.

AGA Resource

The AGA Obesity Practice Guide provides tools for gastroenterologists to lead a multidisciplinary team of health-care professionals for the management of patients with obesity. Learn more at www.gastro.org/obesity.