Most hospitals still use Unfractionated Heparin as the primary agent for Venous Thromboembolism (VTE) prophylaxis and therapy in the inpatient setting due to ease of use and insignificant cost. However, the incidence of Heparin-Induced Thrombocytopenia (HIT) has led to questions about other options for prophylaxis and therapeutic use in the hospital, with more recent data showing that Enoxaparin is safer in terms of incidence of HIT. This study examines the cost-effectiveness of Enoxaparin compared to Heparin for prophylactic and therapeutic usage in a community hospital.
We conducted a retrospective chart review of patients that had HIT panels ordered at the Inspira Health Network, Vineland campus (an approximately 262 bed community hospital located in southern New Jersey that services a population of approximately 61,050) from the period of April 1, 2015 through December 31, 2016. The starting date represents the time from which Enoxaparin became the primary alternative anticoagulant available at this hospital. Records of the total usage and cost of Heparin and Enoxaparin for the specified time period were collected from the hospital pharmacy database for evaluation, as were records of Heparin-Induced Thrombocytopenia (HIT) panels. The information was analyzed to establish whether or not a significant proportion of HIT panels was ordered for patients on Heparin versus Enoxaparin. Annual cost-savings for the hospital were extrapolated by using the comparative incidences of HIT panels and associated costs, including increased inpatient length of stay, hematology consultation, use of an alternative anticoagulant, and complications of Heparin-Induced Thrombocytopenia and Thrombosis (HITT). These variables were multiplied by the incidence rate for each specified drug and usage in order to determine the daily cost for each drug.
The overall use of Enoxaparin did not result in a significant decrease in the ordering of HIT panels in the hospital, with a relative rate ratio of 0.948 (95% Confidence Interval: 0.336, 2.21). However, when the data was stratified to reflect prophylactic and therapeutic usages of Enoxaparin and Heparin, there was a marked difference in the use of therapeutic Intravenous (IV) Heparin as opposed to therapeutic Enoxaparin. The rate ratio of HIT panel ordering when using therapeutic Enoxaparin instead of IV Heparin was 0.118 (0.006, 0.625). These numbers were used to extrapolate the total daily cost of Enoxaparin and IV Heparin; therapeutic Enoxaparin cost $30.62, while IV Heparin cost $161.94. IV Heparin use was associated with a higher incidence rate of HIT panel orders, and subsequently a higher daily cost due to the likelihood of increased length of stay, use of alternative anticoagulation, request for expert consultation, and complication of HITT.
Enoxaparin is associated with a significant cost-saving when used for therapy for patients with venous thromboembolism, when compared to IV Heparin.
No relevant conflicts of interest to declare.
Asterisk with author names denotes non-ASH members.