In ESRD, bariatric surgery lowers risk for death, ups odds for transplant
Adults with obesity receiving dialysis treatment who underwent bariatric surgery were 30% less likely to die of any cause and 82% more likely to undergo kidney transplantation at 5 years compared with similar adults receiving usual care.
“A large proportion of patients on dialysis in the United States also have obesity, yet there has been little uptake of bariatric surgery in this population because of concerns that it is too high risk and also may lead to worse long-term outcomes,” Kyle H. Sheetz, MD, MSc, a general surgery resident at the University of Michigan School of Medicine, told Healio. “This latter point comes from a well-documented association between higher BMI and better long-term survival among dialysis patients, often referred to as the obesity paradox. But obesity is becoming more common in patients on dialysis who already have high baseline rates of diabetes and cardiovascular disease. Evidence suggests bariatric surgery is effective in addressing both of these problems among patients without end-stage renal disease. We asked whether there are also opportunities to improve the health of patients with ESRD and obesity.”
In a retrospective study published in JAMA Surgery, Sheetz and colleagues analyzed data from 1,597 adults with a BMI of at least 35 kg/m² receiving dialysis who underwent bariatric surgery between 2006 and 2015 (mean age, 50 years; 38.5% black), as well as a matched cohort of 4,750 adults who received standard care (mean age, 52 years; 38.6% black), using data from United States Renal Data System registry. Researchers used Cox proportional hazard models to evaluate differences in outcomes for patients who underwent bariatric surgery vs. standard care. Primary outcome was all-cause mortality at 5 years; secondary outcomes were disease-specific mortality and incidence of renal transplant.
Researchers found that surgery was associated with lower all-cause mortality at 5 years compared with usual care, with a cumulative incidence of 25.6% vs. 39.8% (adjusted HR = 0.69; 95% CI, 0.6-0.78). Patients who underwent surgery were also half as likely to die of CV causes at 5 years vs. controls (8.4% vs. 17.2%; aHR = 0.51; 95% CI, 0.41-0.65).
Researchers also found individuals in the surgery cohort were more likely to undergo kidney transplant at 5 years vs. controls (33% vs. 20.4%; aHR = 1.82; 95% CI, 1.58-2.09).
All-cause mortality was higher among those who underwent surgery at 1 year compared with controls, with a cumulative incidence of 8.7% vs. 7.7% (aHR = 1.45; 95% CI, 1.13-1.85).
“This study suggests that bariatric surgery is associated with significant long-term health benefits to patients with obesity on dialysis,” Sheetz said. “Bariatric surgery decreases all-cause mortality and mortality from CV events, which are higher among the ESRD population. It also appears to be associated with a higher likelihood of kidney transplant.”
Sheetz said the findings highlight a need for prospective randomized trials comparing bariatric surgery with standard care for patients with ESRD.
“We also need to better understand how bariatric surgery may be used as a tool to get more patients to transplant and improve their outcomes once transplanted,” Sheetz said.
For more information
Kyle H. Sheetz, MD, MSc, can be reached at the Center for Healthcare Outcomes and Policy, University of Michigan School of Medicine, 2800 Plymouth Road, NCRC B016, Room 100N-11, Ann Arbor, MI 48109; email: firstname.lastname@example.org; Twitter: @KyleSheetz.