Real-world comparative effectiveness of dalteparin and enoxaparin for venous thromboembolism prophylaxis

Venous thromboembolism (VTE) is a preventable cause of significant morbidity and mortality in hospitalized patients world-wide. In Australia, the low-molecular weight heparins (LMWHs) enoxaparin or dalteparin are usually used as first-line prophylaxis for VTE, though there is uncertainty whether dalteparin has the same effectiveness as enoxaparin in real-world settings. This is relevant because dalteparin is less renally cleared and may be more cost effective than enoxaparin. The aim of this study was to explore VTE event incidence in a general cohort of hospitalized adult inpatients who were prescribed enoxaparin or dalteparin for VTE prophylaxis. A retrospective observational study was conducted at a quaternary hospital in Brisbane, Australia, of patients who had experienced a hospital-acquired VTE from 1 September 2021 to 1 March 2023. Patients were identified from routinely collected data following an in-hospital VTE event, and further data was retrieved retrospectively from the integrated electronic Medical Record (ieMR). Incidence and type of VTE events, LMWH-prescribing patterns, and risk factors were assessed. The incidence of VTE events were similar across the dalteparin and enoxaparin cohorts (42.1 events/10 000 patients vs. 34.4 events/10 000 patients, respectively), although patients prescribed enoxaparin had a higher number of risk factors, particularly obesity and active cancer. Our research indicates comparable incidence of VTE in patients prescribed dalteparin compared with enoxaparin in an Australian hospital general cohort of adult inpatients. Dalteparin may be as effective as enoxaparin for VTE prophylaxis in a real-world cohort of patients, and as such dalteparin may be considered a suitable alternative to enoxaparin for VTE prophylaxis. Further research including large randomized controlled trials are required to confirm these results.