Patients With Obesity and ESRD See Survival Benefit From Bariatric Tx

Even for people with obesity and end-stage renal disease (ESRD), bariatric surgery may help slash mortality risk, researchers reported.

In a retrospective cohort study of over 6,000 individuals with obesity and ESRD, those who underwent bariatric surgery saw a 31% reduced risk for all-cause mortality at 5 years (HR 0.69, 95% CI 0.60-0.78), according to Kyle Sheetz, MD, of the University of Michigan in Ann Arbor, and colleagues.

Also at 5 years, 25.6% of those who received bariatric surgery died from any cause, including withdrawal from dialysis, versus about 40% of those who received usual care, they stated in JAMA Surgery.

The reduced morality risk associated with bariatric surgery was mainly driven by a decrease in cardiovascular-related mortality at 5 years: cumulative incidence was 8.4% for those who received bariatric surgery vs 17.2% in nonsurgical control patients (HR 0.51, 95% CI 0.41-0.65), the authors noted.

However, bariatric surgery among this population came with risks, specifically a higher risk of all-cause mortality 1-year post-op (8.6% vs 7.7%, HR 1.45, 95% CI 1.13-1.85).

As for kidney outcomes, bariatric surgery was also tied to an 82% higher chance of undergoing a kidney transplant at 5 years (HR 1.82, 95% CI 1.58-2.09). The cumulative incidence was 33.0% for patients who received bariatric surgery versus 20.4% for usual care.

“This study addresses that gap in evidence to determine whether the long-term health effects of bariatric surgery are transferable to patients with end-stage kidney disease,” the researchers stated, adding that these findings “substantiate practice changes that others have proposed, potentially using bariatric surgery as a means of increasing transplant rates.”

Sheetz’s group drew upon data from the United States Renal Data System registry from 2006 to 2015. A total of 1,597 adults with ESRD and obesity underwent bariatric surgery, including sleeve gastrectomy, Roux-en-Y gastric bypass, gastric banding, or duodenal switch. They were compared with 4,750 matched nonsurgical controls who received usual care alone.

The two groups were matched for age, demographic factors, and comorbid diseases, the most common of being hypertension and type 2 diabetes. One exclusion criteria included having a BMI less than 35. The majority of individuals had a BMI of 45 or greater.

In an invited commentary, Melina Kibbe, MD, and David Gerber, MD, both of the University of North Carolina at Chapel Hill, said these findings clearly indicate that individuals with ESRD can benefit from bariatric surgery.

They questioned why more eligible people do not undergo this treatment given its benefits, and suggested that the answer may be the higher risk of perioperative complications, along with short-term mortality, among bariatric surgery patients on dialysis.

“However, recent studies have demonstrated that the risk of bariatric surgery for patients receiving dialysis is not as high as originally thought,” they pointed out.

Kibbe and Gerber called for a head-to-head analysis comparing survival among those who underwent bariatric surgery versus those who underwent bariatric surgery plus a kidney transplant, as those who undergo both are expected to have a “significantly increased life span.”

“Bariatric surgeons need to look beyond the short-term increased risk of surgery in this patient population and consider the vast survival benefits for patients made eligible for kidney transplant,” they pointed out, adding, “we believe that bariatric surgeons should be incentivized to operate on this patient population instead of being penalized through public reporting because of the risks of higher morbidity.”

“Only when this becomes a reality will the long-term benefits for this challenging patient population be truly realized,” Kibbe and Gerber concluded.