PCV5 - clinical outcomes and treatment patterns of venous thromboembolism among cancer patients in a large commercial database

Abstract

OBJECTIVES: Describe venous thromboembolism (VTE) treatment patterns and clinical outcomes among cancer patients. METHODS: Adult patients (age >18 years)with ?2 VTE diagnosis claims (ICD-9-CM codes) in an outpatient setting or oneVTE diagnosis in an inpatient setting were selected from the Humedica database(01JAN2008-31MAR2014). Continuous health plan enrollment 6 months pre-indexdate (VTE diagnosis) was required. Cancer patients (ICD-9 codes for cancer diagnosis, medication use, radiation therapy, or surgery) were differentiated from activecancer patients (ICD-9 codes for cancer diagnosis and treatment) based on diagnosiscodes during baseline period. VTE treatment patterns with low molecular weightheparin (LMWH), unfractionated heparin (UFH), fondaparinux and oral anticoagulants (OACs) were evaluated. Incidence rate (in person-years) was calculated forclinical outcomes: VTE recurrence, bleeding, major bleeding and clinically relevantnon-major bleeding. RESULTS: Patients with active cancer were on average sicker(Charlson Comorbidity Index score: 6.7 vs. 2.9) and had higher proportions of numerous comorbid conditions, including respiratory disease (52.7% vs. 40.4%), hepaticdisease (14.9% vs. 6.1%) and baseline bleeding (30.4% vs. 17.8%) compared to allcancer patients. More than 70% of cancer patients were prescribed anticoagulants,and the majority received a combination of parenteral andoral anticoagulant treatment. A higher proportion of active cancer patients received only parenteral anticoagulant compared to all cancer patients (26.1% vs. 16.2%), and LMWH was themost commonly prescribed parenteral anticoagulant. The incidence rate of VTErecurrence (24.7 vs. 14.3 per 100 person-years) and major bleeding events (31.2 vs.15.9 per 100 person-years) was higher among active cancer patients than all VTEcancer patients. CONCLUSIONS: Approximately 30% of VTE cancer patients didnot receive any anticoagulation, with difference in treatment patterns betweenVTE cancer and active cancer patients. Active cancer patients had higher incidencerates of VTE recurrence and bleeding events compared to all VTE cancer patients.