Study shows bariatric surgery outperforms GLP-1 diabetes drugs for kidney protection

A Cleveland Clinic study showed that in patients with type 2 diabetes, obesity, and chronic kidney disease, bariatric surgery was associated with a significant decrease in the progression of chronic kidney disease compared to those who received GLP-1 diabetes medications. The paper was published in Annals of Surgery.

According to the Centers for Disease Control and Prevention, more than 1 in 7 U.S. adults are estimated to have chronic kidney disease, which can lead to renal failure. Chronic kidney disease is the longstanding disease of the kidneys which can lead to renal failure. Kidneys filter waste through the blood. As kidneys begin to fail, that waste can build up. Some patients need dialysis, which filters the blood through a machine.

Ali Aminian, M.D., lead author of the study and director of Cleveland Clinic’s Bariatric & Metabolic Institute, said, “Our study shows that bariatric surgery can protect the kidneys and prevent the worsening of kidney function. In patients with obesity and type 2 diabetes who already have established chronic kidney disease, bariatric surgery can change the trajectory of the disease.”

The study included 425 adult patients (ages 18 to 75) with type 2 diabetes, obesity, and stage 3 or 4 chronic kidney disease. Among the study participants, 183 patients underwent bariatric surgery while 242 patients were treated with GLP-1 receptor agonist medications.

Patients involved in the study underwent bariatric surgery between 2010 and 2017 or continuously received GLP-1 medications that were FDA-approved and available during the timeframe of the study. In the nonsurgical group, the most common GLP-1 medications were liraglutide and exenatide. During follow-up, 20% of patients in the nonsurgical group received newer GLP-1 medications such as semaglutide (Ozempic) or tirzepatide (Mounjaro) at some point.

Researchers found that bariatric surgery could protect kidney function and reduce the risk of kidney failure or death in patients. Specifically, study findings showed that bariatric surgery was associated with a 60% lower risk of progression of kidney disease and a 44% lower risk of developing kidney failure or death in comparison to the nonsurgical group.

Over the length of the eight-year study, researchers also found that 22% of the participants in the surgical group experienced progression of kidney disease compared to 45% in the non-surgical group. In addition, 24% in the surgical group developed kidney failure or died over the seven-year span of the study, compared to 44% in the non-surgical group.

The study participants who underwent bariatric surgery experienced more weight loss and better control of their diabetes. They also required less medication to control their diabetes, high blood pressure and high cholesterol.

“Despite its kidney-protective benefits, bariatric surgery is underutilized in clinical practice,” said Dr. Aminian. “In the current management guidelines of chronic kidney disease, while maintaining a healthy weight through lifestyle changes is advised, the option of bariatric surgery has not been considered.”

Jonathan Taliercio, D.O., a nephrologist at Cleveland Clinic and co-author of the study, added, “These numbers are promising and show bariatric surgery should be considered as a treatment option for patients with chronic kidney disease and obesity.”

Dr. Aminian said that GLP-1 receptor agonist medications are quickly evolving, and the role they have in combination with bariatric surgery needs further investigation.