Body Mass Index is Predictive of Higher In-hospital Mortality in Patients Undergoing Laparoscopic Gastric Bypass but Not Laparoscopic Sleeve Gastrectomy or Gastric Banding

High body mass index (BMI) has been shown to be a factor predictive of increased morbidity and mortality in several single-institution studies. Using the University HealthSystem Consortium clinical database, we examined the impact of BMI on in-hospital mortality for patients who underwent laparoscopic gastric bypass, sleeve gastrectomy, and gastric banding between October 2011 and February 2014. Outcomes were examined within each procedure according to BMI groups of 35 to 49.9, 50.0 to 59.9, and 60.0 kg/m² or greater. Outcome measures included in-hospital mortality, major complications, length of hospital stay, 30-day readmission, and cost. A total of 40,102 bariatric procedures were performed during this time period. For gastric bypass, there was an increase of in-hospital mortality (0.01 and 0.02 vs 0.34%; P < 0.01) and major complications (0.93 and 0.99 vs 2.62%; P < 0.01) in the BMI 60 kg/m² or greater group. In contrast, sleeve gastrectomy and gastric banding had no association between BMI and rates of mortality and major complications. Cost increased with increasing BMI groups for all procedures. A strong association was found between BMI 60 kg/m² or greater and higher in-hospital mortality and major complication rates for patients who underwent laparoscopic gastric bypass but not in patients who underwent sleeve gastrectomy or gastric banding.