Incidence of VTE Among Patients with a Cancer Diagnosis in Oklahoma County

Background: Patients with cancer are at elevated risk for venous thromboembolism (VTE). Active cancer contributes a 4-7 fold increased risk for VTE; however, the incidence of VTE stratified by subpopulations of patients diagnosed with cancer, especially race/ethnicity, is uncertain. Objective: Describe the incidence of VTE among adult patients (age ≥ 18 years) with a cancer diagnosis in Oklahoma County, OK according to age, gender, race, and cancer type. Methods: In collaboration with the Centers for Disease Control and Prevention, we established a population-based surveillance system for VTE in Oklahoma County, OK between April 1, 2012-March 31, 2014 to estimate the incidences of first-time and recurrent VTE events. The Commissioner of Health made VTE a reportable condition and delegated surveillance-related responsibilities to the University of Oklahoma, College of Public Health. Active surveillance involved reviewing imaging studies (e.g., chest computed tomography and compression ultrasounds of the extremities) from all inpatient and outpatient facilities in the county and collecting demographic, treatment and risk factor data on all VTE case-patients. Patients were linked to the Oklahoma Central Cancer Registry. Any patient with a cancer diagnosis since 1997, excluding basal or squamous cell carcinoma, were included in the population-at-risk. Active cancer was defined as metastatic or a diagnosis ≤6 months before their VTE diagnosis. Poisson regression was used to estimate incidence rates (IRs) and 95% confidence intervals (CIs), which are reported per 1,000 person years (PY). Estimates with