Morbidity and mortality risk associated with bariatric surgery was found to be higher in patients with super-super morbid obesity, defined as body mass index (BMI) ≥70 kg/m2, but the absolute risk was still relatively low, according to study results published in the journal Surgery for Obesity and Related Diseases.
While the benefits of bariatric surgery are numerous, careful patient selection is vital. Patients with higher BMI have the greatest potential to benefit from these interventions but are also more likely to develop complications. As limited data are available on the risk to benefit ratio of bariatric surgery for patients with BMI ≥70 kg/m2, the goal of the current study was to assess 30-day morbidity and mortality rates in a population of patients with super-super morbid obesity who underwent surgical treatment for weight loss.
The researchers used data from the American College of Surgeons-National Surgical Quality Improvement Project database and identified patients with BMI ≥70 kg/m2 who underwent primary laparoscopic sleeve gastrectomy (SG) or laparoscopic Roux-en-Y gastric bypass (RYGB), as well as a control group that included other patients with BMI <70 kg/m2 who underwent these procedures. The primary outcomes were 30-day morbidity and mortality and postoperative length of stay between the groups.
A total of 163,413 patients underwent primary bariatric surgery during the study period, including 94,188 (57.6%) patients who underwent RYGB and 69,225 (42.4%) who underwent SG. Of the total cohort, 2322 (1.4%) patients had BMI ≥70 kg/m2 (mean age, 40.18 years; 33.2% men), including 1368 (58.9%) patients who underwent RYGB and 954 (41.1%) who underwent SG.
Mortality risk was higher for patients with BMI ≥70 kg/m2 compared with those with BMI <70 kg/m2 (0.4% vs 0.1%, respectively; odds ratio [OR], 3.3; 95% CI, 1.7-6.4; P =.002), as was risk for major (OR, 1.5; 95% CI, 1.3-1.8; P =.001) and minor complications (OR, 1.8; 95% CI, 1.4-2.2; P =.001). In addition, BMI ≥70 kg/m2 was linked to longer mean postoperative length of stay (2.66 vs 2.18 days; P <.0001) and operative time (126.1 vs 114.5 minutes; P =.0001).
In analyzing which complications were more common with BMI ≥70 kg/m2, the researchers found an increased risk for deep vein thrombosis (0.6% vs 0.3%; P =.007) and pulmonary (1.9% vs 0.5%; P =.0001), renal (0.9% vs 0.2%; P =.0001), and infectious complications (1.1% vs 0.4%; P =.0001) in the higher BMI group.
There was no statistically significant difference between groups in the risk for myocardial infarction, pulmonary embolism, or transfusion requirements.
A comparison of RYGB and SG in the group of patients with BMI ≥70 kg/m2 showed that RYGB had a higher association with mortality (OR, 3.7 [95% CI, 1.1-12.0] vs 3.0 [95% CI, 1.1-6.9]), minor complications (OR, 2.0 [95% CI, 1.3-3.0] vs 1.7 [95% CI, 1.3-2.1]), and major complications (OR, 1.7 [95% CI, 1.2-2.3] vs 1.4 [95% CI, 1.1-1.7]).
The researchers acknowledged several study limitations, including consideration of events that occurred only during the 30 days after surgery, no assessment of the benefit of the intervention, and possible unmeasured confounders.
Taken together, the results suggested that rates of morbidity and mortality after undergoing bariatric surgery were relatively low overall but slightly higher in individuals with super-super morbid obesity. More research is needed in this population to support evidence-based operative planning in patients with very high BMI.
Romero-Velez G, Pechman DM, Flores FM, Atkin EM, Choi J, Camacho DR. Bariatric surgery in the super-super morbidly obese: outcome analysis of patients with BMI over 70 using the ACS-NSQIP database [published online April 2, 2020]. Surg Obes Relat Dis. doi:10.1016/j.soard.2020.03.025