Factors Associated With the Choice of Oral Anticoagulant Class in the Older Patients: An Observational Study

Abstract

Aim: Oral anticoagulants are the first-line drugs for treating thrombotic disorders related to nonvalvular atrial fibrillation and for treating deep vein thrombosis, diseases that increase in prevalence with age. Older patients have a greater risk of thrombotic and hemorrhagic events and are more prone to drug interactions. Given this backdrop, we wanted to determine the factors associated with the prescription of direct oral anticoagulants and vitamin K antagonists in older patients. Methods: We performed a cross-sectional observational study using a hospital prescription database. The study population consists of 405 older patients who were given oral anticoagulants. The 2 variables of interest were the prescription of 1 of the 2 classes of oral anticoagulants (direct oral anticoagulants vs vitamin K antagonists) and appropriateness of oral anticoagulant prescribing according to Summary of Product Characteristics (potentially inappropriate vs appropriate). Results: The factors associated with direct oral anticoagulant prescribing were the female gender (odds ratio [OR]: 1.87, 95% confidence interval [CI]: 1.22-2.88) and initiation during hospital stay (OR: 2.56, 95% CI: [1.52-4.32]). Stage 4 and 5 chronic kidney diseases (OR: 0.39, 95% CI: [0.19-0.79] and OR: 0.07, 95% CI: [0.01-0.53]) were factors favoring vitamin K antagonist prescription. Being 90 years of age or more (OR: 2.05, 95% CI: [1.06-3.98]) was a factor for potentially inappropriate anticoagulant prescribing. The gastroenterology department (OR: 2.91, 95% CI: [1.05-8.11]) was associated with potentially inappropriate anticoagulant prescribing. Conclusions: Direct oral anticoagulants are the drugs of choice for anticoagulant treatment, including in older adults. The female gender and the initiation during hospital stay increased the chances of being prescribed a direct oral anticoagulant in older adults. Stage 4 and 5 chronic kidney disease increased the likelihood of having a vitamin K antagonist prescribed. Our study also revealed a persistence of potentially inappropriate oral anticoagulant prescriptions in older patients.