Bariatric Surgery Lowers Risk of Liver, Heart, and Kidney Complications in Liver Disease

Metabolic bariatric surgery (MBS) has long been recognized as one of the most effective interventions for obesity, offering durable weight loss and metabolic improvements. Now, new research argues its benefits extend even further, showing that MBS substantially reduces not only liver-related complications but also other health risks in patients with steatotic liver disease (SLD).¹

Published in Diabetes, Obesity and Metabolism, the large-scale retrospective analysis showed that MBS reduced the risk of cardiovascular, renal, and cancer risks among more than half a million patients with the liver disease.

Guidelines, including from the American Society for Metabolic and Bariatric Surgery, already recommend considering MBS in patients with obesity and early-stage SLD.²

SLD, formerly known as nonalcoholic fatty liver disease, is one of the fastest-rising causes of chronic liver disease worldwide. Left untreated, the disease can progress to cirrhosis, liver failure, or hepatocellular carcinoma, while also elevating the risk of heart disease, kidney dysfunction, and obesity-related cancers.

In this new study, investigators identified approximately 15,000 patients who had undergone MBS and matched them to 540,000 patients with SLD who had not received surgery.¹ After propensity score matching to balance for age, sex, comorbidities, and metabolic factors, each cohort included 14,970 participants. The mean follow-up period was just over 4 years.

The group observed that MBS was associated with a 16% lower risk of major liver events (HR, 0.84; 95% CI, 0.75-0.95), the study’s primary end point. Secondary outcomes included impact on cardiovascular, kidney, cancer, and all-cause mortality risk.

Compared with nonsurgical patients, those who had MBS experienced:

• 16% lower risk of major liver events (HR, 0.84; 95% CI, 0.75-0.95)
• 48% lower risk of cardiovascular events such as heart attack, stroke, or heart failure (HR, 0.52; 95% CI, 0.47-0.57)
• 46% lower risk of kidney complications (HR 0.54; 95% CI, 0.41-0.72)
• 42% lower risk of obesity-related cancers (HR 0.58; 95% CI, 0.50-0.67)
• 51% lower all-cause mortality (HR 0.49; 95% CI, 0.43-0.56)

Based on their findings, the researchers argue, “A diagnosis of SLD should be considered a significant clinical criterion to prompt referrals of patients living with obesity to bariatric surgical centers.”

Notably, both major bariatric techniques—sleeve gastrectomy and Roux-en-Y gastric bypass—yielded comparable benefits. Subgroup analyses confirmed that these advantages were especially pronounced among patients with type 2 diabetes or a body mass index (BMI) above 50 kg/m². In contrast, patients without diabetes or extreme obesity still experienced substantial reductions in extrahepatic complications, though the hepatic benefits were less marked.

While sustained weight loss is a clear driver of improved metabolic and hepatic health, the researchers noted that the benefits of MBS extended well beyond reduced body mass. Within days after surgery, often before significant weight loss occurs, patients demonstrated improved insulin sensitivity, better glucose regulation, and decreased systemic inflammation.

The overall postoperative complication rate was low at 1.5% within 30 days of surgery, and 30-day mortality was 0.2%. These findings reinforce that MBS can be safely performed in patients with non-cirrhotic SLD, particularly in specialized bariatric centers.

The study’s researchers acknowledged certain limitations, including its observational nature and the lack of granular data on liver fibrosis stage, alcohol consumption, or socioeconomic factors.

As new pharmacologic treatments such as GLP-1 receptor agonists and thyroid hormone receptor–β agonists gain traction in managing metabolic liver disease, future research will explore how these therapies can complement surgical interventions, noted the researchers.

References:

1. Stupalkowska W, Henney A, Sheu EG Alam U, Cuthbertson DJ. Metabolic bariatric surgery is associated with reduced adverse hepatic and extrahepatic outcomes, and lower all-cause mortality, in patients with steatotic liver disease. DOEM and Diabetes Obes Metab. Published online September 30, 2025. doi:10.1111/dom.70173

2. Eisenberg D, Shikora SA, Aarts E, et al. 2022 American Society for Metabolic and Bariatric Surgery (ASMBS) and International Federation for the Surgery of obesity and metabolic disorders (IFSO): indications for metabolic and bariatric surgery. Surg Obes Relat Dis. 2022;18(12):1345-1356. doi:10.1016/j.soard.2022.08.013