Venous thromboembolism: risk factors in the sleeve gastrectomy era

Cumulative Incidence of Venous Thromboembolic Events In-Hospital, and at 1, 3, 6, and 12 Months After Metabolic and Bariatric Surgery: Systematic Review of 87 Studies and Meta-analysis of 2,731,797 Patients

Systematic review/meta-analysis of cumulative incidences of venous thromboembolic events (VTE) after metabolic and bariatric surgery (MBS). Electronic databases were searched for original studies. Proportional meta-analysis assessed cumulative VTE incidences. (PROSPERO ID:CRD42020184529). A total of 3066 records, and 87 studies were included (N patients = 4,991,683). Pooled in-hospital VTE of mainly laparoscopic studies = 0.15% (95% CI = 0.13-0.18%); pooled cumulative incidence increased to 0.50% (95% CI = 0.33-0.70%); 0.51% (95% CI = 0.38-0.65%); 0.72% (95% CI = 0.13-1.52%); 0.78% (95% CI = 0-3.49%) at 30 days and 3, 6, and 12 months, respectively. Studies using predominantly open approach exhibited higher incidence than laparoscopic studies. Within the first month, 60% of VTE occurred after discharge. North American and earlier studies had higher incidence than non-North American and more recent studies. This study is the first to generate detailed estimates of the incidence and patterns of VTE after MBS over time. The incidence of VTE after MBS is low. Improved estimates and time variations of VTE require longer-term designs, non-aggregated reporting of characteristics, and must consider many factors and the use of data registries. Extended surveillance of VTE after MBS is required.

Predicting short-term thromboembolic risk following Roux-en-Y gastric bypass using supervised machine learning

BACKGROUND

Roux-en-Y gastric bypass (RYGB) is a widely recognized bariatric procedure that is particularly beneficial for patients with class III obesity. It aids in significant weight loss and improves obesity-related medical conditions. Despite its effectiveness, postoperative care still has challenges. Clinical evidence shows that venous thromboembolism (VTE) is a leading cause of 30-d morbidity and mortality after RYGB. Therefore, a clear unmet need exists for a tailored risk assessment tool for VTE in RYGB candidates.

AIM

To develop and internally validate a scoring system determining the individualized risk of 30-d VTE in patients undergoing RYGB.

METHODS

Using the 2016-2021 Metabolic and Bariatric Surgery Accreditation Quality Improvement Program, data from 6526 patients (body mass index ≥ 40 kg/m2) who underwent RYGB were analyzed. A backward elimination multivariate analysis identified predictors of VTE characterized by pulmonary embolism and/or deep venous thrombosis within 30 d of RYGB. The resultant risk scores were derived from the coefficients of statistically significant variables. The performance of the model was evaluated using receiver operating curves through 5-fold cross-validation.

RESULTS

Of the 26 initial variables, six predictors were identified. These included a history of chronic obstructive pulmonary disease with a regression coefficient (Coef) of 2.54 (P < 0.001), length of stay (Coef 0.08, P < 0.001), prior deep venous thrombosis (Coef 1.61, P < 0.001), hemoglobin A1c > 7% (Coef 1.19, P < 0.001), venous stasis history (Coef 1.43, P < 0.001), and preoperative anticoagulation use (Coef 1.24, P < 0.001). These variables were weighted according to their regression coefficients in an algorithm that was generated for the model predicting 30-d VTE risk post-RYGB. The risk model's area under the curve (AUC) was 0.79 [95% confidence interval (CI): 0.63-0.81], showing good discriminatory power, achieving a sensitivity of 0.60 and a specificity of 0.91. Without training, the same model performed satisfactorily in patients with laparoscopic sleeve gastrectomy with an AUC of 0.63 (95%CI: 0.62-0.64) and endoscopic sleeve gastroplasty with an AUC of 0.76 (95%CI: 0.75-0.78).

CONCLUSION

This simple risk model uses only six variables to assist clinicians in the preoperative risk stratification of RYGB patients, offering insights into factors that heighten the risk of VTE events.

County health ranking: untangling social determinants of health and other factors associated with short-term bariatric surgery outcomes

BACKGROUND

The complex interplay of the social determinants of health, race/ethnicity, and traditional surgical risk factors on outcomes following metabolic surgery is poorly understood.

OBJECTIVE

To evaluate the relationship between the social determinants of health as measured by county health ranking (CHR) and short-term metabolic surgery outcomes.

SETTING

Five accredited bariatric program sites at a national academic health system.

METHODS

Data were collected from 5 sites of a single health system from 2010 to 2021. Current procedural terminology codes identified primary and revisional cases. Patient characteristics, procedural data, and 30-day occurrences were collected. CHRs for health factors were determined by ZIP Code and stratified into best, middle, and worst terciles. The primary outcome was 30-day complications, readmissions, or reinterventions/reoperations. Logistic regression assessed the correlation between CHR tercile and morbidity.

RESULTS

We analyzed 4,315 primary and 370 revisional metabolic surgery cases. Overall, 64.0%, 27.4%, and 8.6% of patients lived in the best, middle, and worst CHR terciles, respectively. Patients in the middle and worst CHR terciles were more commonly older; non-Hispanic Black or Hispanic; suffered from preexisting chronic obstructive pulmonary disease or hypertension, were dialysis dependence, were on therapeutic anticoagulation, or had inferior vena cava filters. Middle and worst CHR tercile patients were more likely to undergo index sleeve gastrectomy or robotic-assisted surgery and have surgery performed by a self-designated general surgeon. Thirty-day outcomes were similar across CHR terciles. Racial disparity in multiple short-term outcomes persisted despite adjustment for CHR tercile.

CONCLUSION

Higher-risk patients are more likely to be from counties with lower CHRs, but CHR was not independently associated with 30-day outcomes after metabolic surgery.

Portomesenteric Vein Thrombosis in Patients Undergoing Sleeve Gastrectomy: an Updated Systematic Review and Meta-Analysis of 101,914 Patients

INTRODUCTION

Portomesenteric vein thrombosis (PMVT) is a rare but potentially fatal complication of sleeve gastrectomy (SG). The rising prevalence of SG has led to a surge in the occurrence of PMVT, while the associated risk factors have not been fully elucidated. This study aims to determine the incidence and risk factors of PMVT in patients undergoing SG.

METHODS

A comprehensive literature search was performed in PubMed and EMBASE databases. Proportion and regression meta-analyses were conducted.

RESULTS

In a total of 76 studies including 101,914 patients undergoing SG, we identified 357 patients with PMVT. Mean follow-up was 14.4 (SD: 16.3) months. The incidence of PMVT was found to be 0.50% (95%CI: 0.40-0.61%). The majority of the population presented with abdominal pain (91.8%) at an average of 22.4 days postoperatively and PMVT was mainly diagnosed with computed tomography (CT) (96.0%). Hematologic abnormalities predisposing to thrombophilia were identified in 34.9% of the population. Advanced age (p=0.02) and low center volume (p <0.0001) were significantly associated with PMVT, while gender, BMI, hematologic abnormality, prior history of deep vein thrombosis or pulmonary embolism, type of prophylactic anticoagulation, and duration of prophylactic anticoagulation were not associated with the incidence of PMVT in meta-regression analyses. Treatment included therapeutic anticoagulation in 93.4% and the mortality rate was 4/357 (1.1%).

CONCLUSION

PMVT is a rare complication of sleeve gastrectomy with an incidence rate <1% that is associated with low center volume and advanced age but is not affected by the duration or type of thromboprophylaxis administered postoperatively.

Gastric Bypass Mortality Trends in Racial Cohorts: Are We Improving?

INTRODUCTION

Roux-en-Y gastric bypass (RYGB) continues to be safely performed in racial cohorts. However, studies continue to report differences in complications, with non-Hispanic black (NHB) patients having a higher rate of adverse outcomes, including mortality. It is unclear how these disparate outcomes have evolved over time. Our objective was to determine RYGB procedure and mortality trends in racial cohorts.

METHODS

Using the 2015 to 2019 Metabolic and Bariatric Surgery Accreditation and Quality Improvement Project (MBSAQIP) database, we identified primary RYGB cases performed laparoscopically or robotically. Non-Hispanic white (NHW) and non-Hispanic black (NHB) patient cohorts were matched based on patient and surgical characteristics. Conditional logistic regression analysis was conducted on the matched pairs. Primary outcomes of interest included year-to-year all-cause and procedure-related mortality. Stata/MP 16.1 was utilized for analysis, and a p-value of < 0.05 and a 95% confidence interval that excluded 1 were considered significant.

RESULTS

A total of 148,829 RYGB cases in NHW (82.8%) and Black (17.2%) patients were analyzed. RYGB trends remain similar for NHB and NHW patients over 5 years. In matched cohorts, all-cause mortality (OR 2.23; 95% CI: 1.16-4.29), aggregate related readmission (OR 1.39; 95% CI: 1.27-1.51), related reintervention (OR 1.36; 95% CI: 1.19-1.56), and VTE (OR 1.86; 95% CI: 1.40-2.45) were more likely in NHB patients. During the study period, year-to-year mortality was higher in NHB patients compared to NHW patients.

CONCLUSION

Over a 5-year period, year-to-year mortality remains higher in NHB patients after RYGB. While bariatric outcomes continue to improve, outcome gaps between racial cohorts seem to persist.

Factors Associated with Increased Risk for Pulmonary Embolism After Metabolic and Bariatric Surgery: Analysis of Nearly One Million Patients

BACKGROUND

Metabolic and bariatric surgery (MBS) has a low incidence of post-operative morbidity and mortality. Understanding risk factors associated with complications that occur allows surgeons to define at-risk patients and assess the need for preventive and prophylactic measures.

OBJECTIVES

To determine risk factors associated with development of pulmonary embolism (PE) within 30 days of MBS and to predict the increased risk for mortality when PE occurs.

SETTING

USA, MBSAQIP database.

METHODS

Analysis of the MBSAQIP database was undertaken. This included information on 966,646 MBS cases from 2015 to 2019 in the USA.

RESULTS

Twenty-two risk factors for development of PE post-MBS were identified to be statistically significant.

CONCLUSIONS

PE is a relatively uncommon complication after MBS. When it does occur, there is a 50.9-fold increased risk for mortality. Patients with significant risk factors for PE may benefit from higher dose perioperative and/or extended VTE prophylaxis after MBS.