Worsening renal function is associated with a greater risk of complications from bariatric surgery, researchers reported.

In a retrospective study of 27,736 patients who underwent bariatric surgery, researchers Nicole A. Turgeon, MD, and colleagues at Emory University in Atlanta, found that each increase in stage of chronic kidney disease (CKD) was associated with a 30% increased risk of experiencing postoperative complications, after adjusting for diabetes and hypertension.

Compared with a reference group that included patients with normal glomerular filtration rate or CKD stage 1, patients with CKD stage 5 had a nearly 2.3 times increased risk of postoperative complications in a fully adjusted model, according to findings published online ahead of print in the Journal of the American Society of Nephrology. Patients with CKD stage 2 and 3 had a 24% and 36% increased risk, respectively. The risk did not increase significantly for patients with CKD stage 4.

Continue Reading

Patients with higher CKD stages had a higher incidence of postoperative pulmonary complications, including pneumonia, prolonged postoperative ventilation, and unplanned reintubation. They also had a higher incidence of postoperative renal complications, such as renal failure and urinary tract infection.

Furthermore, higher CKD stages were associated with a greater likelihood of a return to the operative room. The investigators found that 4.9% of patients with CKD stages 4 or 5 returned to the operating room compared with 2.3%, 2.7%, and 3.1% of those in the reference group and patients with CKD stages 2 and 3, respectively.

The authors observed that although the relative risk of complications from bariatric surgery is higher in patients with higher CKD stages, the absolute risk remains low.

“Clinicians must weight the increased risks against the substantial benefits of surgically induced weight loss when counseling patients with renal disease about bariatric surgery,” the researchers concluded.

In the study population, 20,806 (75%) had a normal estimated GFR or CKD stage 1, 5,011 (18%) had CKD stage 2, 1,734 (6.25%) had CKD stage 3, 94 (0.34%) had CKD stage 4, and 91 (0.33%) had CKD stage 5. Thirty-four patients (0.12%) were on long-term dialysis.