Background

Previous studies demonstrate increased perioperative complications with increasing body mass index (BMI), and significantly increased risk beyond BMI 50kg/m2. Few studies have evaluated the safety of MBS in patients with BMI >70kg/m2. This paper will examine the perioperative complications in patients with extreme obesity (EO) compared to severe obesity (SO) undergoing metabolic surgery.

Methods

The 2015-2020 Metabolic and Bariatrics Surgical Quality Improvement Project (MBSAQIP) Registry was utilized to evaluate patients with EO compared to SO undergoing bariatric surgery. 30-day complications were evaluated using univariate analysis and multivariable regression.

Results

231,195 patients were included; 10,551(4.6%) with EO and 220,644(95.4%) with SO. 160,399(69%) underwent sleeve gastrectomy (SG), and 70,796(31%) underwent gastric bypass (RYGB). Patients with extreme obesity were younger 39.6y vs 42.2y, with a greater proportion of Black patients 3,312(31.4%) vs 51,270(23.2%) compared to SO, all p<0.001. Univariate analysis demonstrated increased complications and mortality with EO versus SO for both SG and RYGB (Table 1). On multivariable regression, EO was independently associated with the following complications: leak rates (AOR 1.54, p=0.001), pulmonary (AOR 2.48, p<0.001), cardiac (AOR 1.98, p=0.001), renal (AOR 4.23, p<0.001), infection (AOR 1.82, p<0.001), VTE (AOR 1.34, p<0.022), bleed (AOR p=0.006), serious complications (AOR 1.46, p<0.001), and mortality (AOR 2.84, p<0.001).

Conclusions

In this national database study, patients with extreme obesity had a significantly higher risk of postoperative complications and mortality compared to those with severe obesity, and with higher risks following RYGB versus LSG. Focused interventions and adjusted perioperative counseling are warranted in in this high-risk population.