Venous and Arterial Thromboembolism Related Hospitalizations Among Patients with Gastrointestinal Malignancy in United States - Data from Nationwide Sample

Introduction:

Patients with underlying malignancies are at high risk for developing venous thromboembolism (VTE). We sought to characterize the risk and risk factors for developing VTE (both deep vein thrombosis (DVT) and Pulmonary embolism (PE)) and arterial thromboembolism among patients with underlying Gastrointestinal(GI) malignancies.

Methods:

We used the Nationwide Inpatient Sample (NIS) database to perform a cross-sectional study. The study group was defined as all hospitalized patients with GI malignancies above 18 years included in the NIS 2011 database with a primary discharge diagnosis of thromboembolism (Venous or arterial), as per the International Classification of Diseases - Clinical Modification, 9th revision (ICD-9-CM) codes. This VTE and arterial embolism population's demographics and outcomes were compared to the remainder of inpatient GI cancer patients without the diagnosis. All analyses were performed using STATA MP 12.VTE and Arterial embolism, identified by the ICD-9-CM codes, were studied comprehensively for their association with GI cancers and the risk factors were using multivariate logistic regression analysis. Odds ratios were calculated adjusting for relevant patient comorbidities.

Results:

Based on the location of GI cancer, there were a total of 37,872 patients hospitalized with underlying diagnosis of esophageal cancer, 97020 patients with pancreatic cancer, 45669 patients with gastric cancer and 267756 patients with colorectal cancer. The rates of VTE were highest among patients with pancreatic cancer (3.3%) followed by esophageal cancer 2.2%; gastric cancer 1.9%; colorectum (1.4%).

In multivariate analysis, risk of VTE diagnosis was highest among pancreatic cancer patients, adjusted Odds ratio (aOR) - 2.8; 95% CI (2.53 - 3.09) after adjusting for active chemotherapy status, race, age, gender and comorbidities as determined by Deyo - Charlson comorbidity index. aOR for risk of VTE among Esophageal cancer patients was 1.73 , 95% CI (1.49-2.01) ; Colorectal cancer 1.18; 95% CI (1.09-1.27) and gastric cancer 1.52, 95% CI(1.30-1,78). The risk of PE was higher than DVT among patients with VTE. Underlying GI cancer was not associated with increased risk of arterial embolization, acute cerebro vascular events or acute myocardial infarction. The number of death associated with a principal discharge diagnosis code of VTE were not significantly high.

Conclusion:

Patients with pancreatic cancer have the highest risk of hospitalization for VTE among patients with underlying GI malignancies. Underlying GI malignancy is not associated with increased risk of arterial embolization, acute cerebro vascular events or acute myocardial infarction.