Background: Both low molecular weight heparin (LMWH) administered once daily and unfractionated heparin (UFH) given thrice daily are routinely used for venous thromboembolism (VTE) prophylaxis in the inpatient setting. There is little data regarding a difference in adherence between these regimens.
Aims: The primary outcome was comparison of adherence to LMWH and UFH doses ordered for VTE prophylaxis of medical inpatients. Secondary outcomes included adherence rate among subgroup populations, incidence of VTE, and adherence rates of greater than 80% and 90% of doses ordered.
Methods: This is a retrospective study of 1444 adult patients admitted to a primary medicine team and receiving VTE prophylaxis in a 726-bed tertiary care center from January 1st to October 1st, 2020. Patients with body mass index (BMI) > 40 kg/m2, creatinine clearance < 30 mL/min, and COVID positive status were excluded. Adherence was defined as the percentage of ordered doses documented as administered within the electronic medical record.
Results: 456 patients received LMWH and 998 received UFH. Compared to UFH, LMWH had a significantly higher adherence with a median of 100% [IQR 66.7-100] vs 83.3% [IQR 50.0-97.9] (p<0.001) and mean of 75.7% vs 68.4% (p<0.001). There was a statistically significant increase in adherence among various subgroups including: males, females, age > 50 years old, and BMI 18.5 – 40. Patients in the LMWH group were more likely to have adherence rates of greater than 80% (62.9% vs 52.0%, p<0.001) and 90% (57.0% vs 37.0%, p<0.001) when compared to UFH. There was no statistically significant difference in new VTE events between the LMWH and UFH groups.
Conclusions: Guidelines equally recommend LMWH and UFH for thromboprophylaxis in hospitalized medicine patients. This study demonstrates that LMWH has a higher adherence rate than UFH in the clinical setting, and providers should take this into consideration when making choices about VTE prophylaxis for hospitalized patients.
To cite this abstract in AMA style:
Trybula M, Ahart Z, Stacy E. Comparing Adherence of Low Molecular Weight Heparin versus Unfractionated Heparin for Thromboprophylaxis of Medical Inpatients [abstract]. Res Pract Thromb Haemost. 2021; 5 (Suppl 2). https://abstracts.isth.org/abstract/comparing-adherence-of-low-molecular-weight-heparin-versus-unfractionated-heparin-for-thromboprophylaxis-of-medical-inpatients/. Accessed December 6, 2023.« Back to ISTH 2021 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/comparing-adherence-of-low-molecular-weight-heparin-versus-unfractionated-heparin-for-thromboprophylaxis-of-medical-inpatients/