Suboptimal Use of DOACs Post-Discharge for Geriatric Hip Fractures with Isolated Calf Deep Vein Thrombosis: Do Clinician Prescribing Preferences and Patient Compliance Alters Clinical Outcomes?

Introduction: This study aimed to examine the impacts of DOACs compliance and prescribing preferences on clinical outcomes in elderly hip fracture patients with isolated calf deep vein thrombosis (ICDVT).

Methods: We conducted a retrospective cohort study that evaluated 702 patients who underwent surgical treatment combined with ICDVT in an academic university hospital between January 2016 and October 2021. DOACs compliance was investigated through telephone and outpatient follow-up, and ICDVT clinical outcomes were collected 30 and 90 days post-discharge, respectively. Variables of interest were collected through the electronic medical record system, and data were analyzed after adjusting for predictors of non-completely dissolved (CD) of ICDVT.

Results: The DOACs compliance survey revealed that 375 (53.42%) patients were fully adherent, 270 (38.46%) were fairly adherent, and 57 (8.12%) were poorly adherent. Approximately 62% of patients had ICDVT dissipation within 30 days after discharge, reaching 94% within 90 days. DOACs QD/BID regimen is often based on economic status, activity capacity, discharge destination and post-operative weight-bearing activities (p<0.05).The mechanism of injury, ASA classification, surgical technique and timing of ICDVT formation were significantly correlated with DOACs 14/28 days regimen (p<0.05).Multivariate analysis revealed that rural patients [OR 1.518 (95% CI, 1.117-2.236)], pre-operative ICDVT[OR 2.816 (95% CI, 1.862-4.259)] and thrombus length [OR 1.157 (95% CI, 1.263-1.821)] were ICDVT risk factors for non-CD. Furthermore, DOACs fair compliance [OR 0.087 (95% CI, 0.042-0.178)], DOACs full compliance [OR 0.283 (95% CI, 0.139-0.579)], and hospitalization duration [OR 0.793 (95% CI, 0.694-0.907)] were ICDVT protective factors for CD.

Conclusion: Better compliance with DOACs benefits early ICDVT dissipation, but final clinical outcomes have to be validated with longer follow-up periods. When managing elderly patients with hip fractures, indications for anticoagulation should be considered and individualized protocols should be used.