Long-term changes in coagulation and fibrinolytic profiles after bariatric surgery: a systematic review of literature

To evaluate the long-term, post-bariatric coagulation changes and explore the emergence of a possible coagulopathic state secondary to weight loss. A systematic review of Cochrane, Medline, Web of Science and PubMed was done following PRISMA-guidelines, including post-bariatric patients (≥ 6 months) with measured coagulation parameters (e.g., prothrombin time, clot lysis assay). There were 10 included studies to the qualitative and quantitative analysis, of 546 individuals with a mean age of 42.1 ± 0.45 years, an average female percentage per study being 74.6%, followed for 6–24 months with majority being post-Roux-en Y gastric bypass (RYGB) ( n = 294). The post-bariatric follow-up showcased a significant decrease in inflammatory status, microvesicle-associated tissue factor (MV-TF) activity, D-dimer, fibrinogen and tissue factor. In addition, significant markers of clot lysis (e.g., shorter lag phase with decreased endogenous thrombin production and faster lysis). The long-term haemostasis in post-bariatric surgery appears to shift from the highly prothrombotic condition observed in morbid obesity toward a less coagulable and more fibrinolytic state, which does not necessarily mean a significant clinical risk for bleeding tendency. However, these results raise the possibility of hidden coagulopathy that warrants further studies and analysis.