Abstract 110: Clinical Characteristics and Anticoagulant Transition Patterns of Hospitalized Patients with Venous Thromboembolism: A Retrospective Analysis Using Electronic Health Record Data
Authors: Burton T , Hlavacek P , Guo J D , Rosenblatt L , Mardekian J , Ferri M , Russ C , Kline J. A 
Published: April 2019

Objective:
Describe the clinical characteristics and anticoagulant use of patients with venous thromboembolism (VTE) transitioning from a hospital setting using an electronic health care (EHR) database.

Methods:
This retrospective EHR study analyzed adults (18+ years) with a VTE diagnosis code during a hospital encounter (emergency department [ED], observation [OBS] area, or inpatient [IP] stay) between 1/1/2012-8/31/2017 (ID period). The first VTE hospital encounter (from admission to discharge) during the ID period was defined as the index VTE encounter. Patients with evidence of atrial fibrillation/flutter, pregnancy, or multiple oral anticoagulants during the index VTE encounter were excluded. Clinical characteristics and anticoagulants administered during the index VTE encounter and ordered on the discharge date were reported descriptively.

Results:
Among the 282,978 patients identified, the mean age (SD) age was 61 (17) years; 48% (136,155 of 282,978) were male; 78% (221,120 of 282,978) were Caucasian; 59% (167,628 of 282,978) had deep vein thrombosis without a pulmonary embolism; 18% (49,596 of 282,978) had evidence of cancer; and 7% (19,447 of 282,978) had evidence of a provoked etiology (hormonal therapy, lower extremity fracture/trauma, pelvic/orthopedic surgery) during the index VTE encounter. Nearly three-quarters (199,568 of 282,978) were admitted for an IP stay with a median length of stay of 6 days; the remaining 29% (83,410 of 282,978) were treated in an ED or OBS area only. Overall, 73% (207,640 of 282,978) were discharged home, 19% (54,283 of 282,978) were discharged to another IP facility, and 7% (21,055 of 282,978) had other or unknown discharge status. During the index VTE encounter, 67% (188,271 of 282,978) received heparin (low molecular weight or unfractionated), 34% (95,090 of 282,978) received warfarin, 12% (34,540 of 282,978) received a non-vitamin K oral anticoagulant (DOAC), and 27% (76,877 of 282,978) had no record of anticoagulant administration. Of those with heparin, 41% (76,471 of 188,271) received heparin only. More than half of those with an order for a DOAC or warfarin on the discharge date had received the same anticoagulant during the index VTE encounter, namely, 65% (22,344 of 34,540) with a DOAC during the index VTE encounter received a discharge order for a DOAC and 58% (55,369 of 95,090) with warfarin during the index VTE encounter received a discharge order for warfarin. Among those with heparin only during the index VTE encounter, approximately 18% (13,759 of 76,471) received an order for heparin, 6% (4,217 of 76,471) received an order for a DOAC, and 5% (3,810 of 76,471) received an order for warfarin on discharge.

Conclusion:
This EHR study observed that a sizable proportion of hospitalized patients with VTE were either prescribed a different anticoagulant on discharge or discharged without an anticoagulant prescription.