Impact of Perioperative Thromboembolic Complications on Future Long-term Risk of Venous Thromboembolism among Medicare Beneficiaries Undergoing Complex Gastrointestinal Surgery.

BACKGROUND

Venous thromboembolism (VTE), including deep venous thrombosis (DVT) and pulmonary embolism (PE), represents a common cause of morbidity and mortality following complex gastrointestinal surgery. Whether perioperative VTE also exposes patients to a higher long-term risk of VTE events remains poorly defined.

METHODS

The Medicare 100% Standard Analytic Files were used to identify patients undergoing esophageal, hepatic, pancreatic, and colorectal resection between 2013 and 2017. The impact of perioperative VTE, defined as a VTE episode occurring during the index hospitalization or within 30 days of discharge, on the risk of developing subsequent long-term VTE episodes (i.e., more than 30 days following discharge) was examined.

RESULTS

Among 253,212 patients who underwent complex gastrointestinal surgery, 1.9% (n=4763) developed a VTE episode perioperatively. With a median follow-up period of 553 days (IQR 194-1052), a total of 11,052 patients (4.4%) developed a long-term VTE episode. Of note, patients who developed a DVT perioperatively had a higher risk of experiencing a long-term VTE episode than patients who had no perioperative thromboembolic complications (HR 6.50, 95%CI 6.04-6.98). The increase in risk was more pronounced among patients who had a PE (HR 27.97, 95%CI 25.39-30.80) at the time of surgery. Risk factors for long-term thromboembolic events following complex GI surgery included Black patients (HR 1.20, 95%CI 1.11-1.30), receipt of surgery at a teaching hospital (HR 1.09, 95%CI 1.04-1.13), nonelective surgery (HR 1.19, 95%CI 1.14-1.24), as well as a diagnosis of cancer (HR 1.10, 95%CI 1.05-1.16). The development of a perioperative DVT was associated with an increased long-term risk of VTE in both cancer (HR 5.59, 95%CI 5.29-6.61) and non-cancer patients (HR 6.98, 95%CI 6.37-7.64). Similarly, experiencing a PE at the time of surgery led to a higher long-term risk of VTE in cancer (HR 24.30, 95%CI 21.08-28.02), as well as non-cancer (HR 30.81, 95%CI 27.01-35.15) patients.

CONCLUSIONS

Patients with a history of perioperative VTE had a higher risk of developing subsequent VTE events within 1-2 years following complex GI surgery. The risk was more pronounced among patients who had perioperative PE rather than DVT. These findings were consistent among both cancer and non-cancer patients.