Venous Thromboembolism After Bariatric Surgery: An Analysis of Predictors and Trends in Two Large Datasets

BackgroundDeep vein thrombosis and pulmonary embolism (collectively, venous thromboembolism [VTE]) cause significant morbidity after bariatric surgery. The aim of this study was to compare predictors of VTE after bariatric surgery in two national databases.MethodsThe core National Inpatient Sample (NIS) database and Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) Participant Use data Files from 2016-2021 were concatenated, and elective vertical sleeve gastrectomy and Roux-en-Y gastric bypass procedures were included. Trends in VTE were derived for inpatient hospital stays (NIS and MBSAQIP) and compared and 30-day rates only available in the MBSAQIP were also derived. Preoperative and perioperative factors were identified to construct a multivariable logistic regression model to identify predictors of VTE for each dataset.Results204,866 and 986,210 patients were identified in the NIS and MBSAQIP, and postoperative inpatient VTE rates were 0.11% and 0.10% (P > 0.05), respectively. History of pulmonary embolism (NIS odds ratio [OR] and 95% confidence interval: 3.21 [1.86, 5.53], P < 0.05, MBSAQIP OR: 1.83 [1.45, 2.32], P < 0.05) and increased age (NIS OR: 1.22 [1.02,1.45], P < 0.05, MBSAQIP OR: 1.06 [1.0, 1.11], P < 0.05) were the only factors associated with higher risk of VTE in both databases. There was no difference in in-hospital rates between databases aside from 2021. The MBSAQIP 30-day VTE rate was 0.30%; hence, most (67%) incidences of 30-day VTE occurred after discharge.ConclusionsOur analysis identifies critical risk factors for VTE after bariatric surgery. Most incidences of VTE occurred after the initial hospitalization, and the MBSAQIP underestimates 2021 VTE rates.