Effect of switching from acenocoumarol to phenprocoumon on time in therapeutic range and INR variability: A cohort study

Abstract

Background Treatment with vitamin K antagonists (VKA) requires a high proportion of time in the therapeutic range (TTR) and a low international normalised ratio (INR) variability to be maximally safe and effective. Switching from short-acting acenocoumarol to long-acting phenprocoumon could improve VKA control. Aims We assessed whether switching from acenocoumarol to phenprocoumon improves the time in the therapeutic range (TTR) and INR variability. Methods and results In a retrospective cohort with data on 236,957 patients-years of VKA management from two first-line anticoagulation clinics in the Netherlands, we identified 124 patients in target range 2-3, 269 patients in target range 2-3.5 and 98 patients in target range 2.5-3.5 who switched from acenocoumarol to phenprocoumon. They were matched in a 1:2 ratio to non-switching controls using propensity score matching. Over the first 180 days after a switch, switchers' TTR declined 5 (95% CI 1 to 10), 10 (95% CI 7 to 13) and 5 (95% CI 0 to 11) percentage points relative to nonswitchers, in target ranges 2-3, 2-3.5 and 2.5-3.5. Anticoagulation was more often supra-therapeutic in switchers, and switchers had a higher INR variability. In the following 180 days, TTR in switchers became 1 (95% CI-4 to 6), 4 (95% CI 0 to 7) and 6 (95% CI 1 to 12) percentage points better than in non-switchers. Switchers' INRs were much more stable than non-switchers'. Conclusion Eventually, a switch from acenocoumarol to phenprocoumon leads to a higher TTR and a lower INR variability. However, this is preceded by a transition period with opposite effects.

Comparison of Anticoagulation Quality between Acenocoumarol and Warfarin in Patients with Mechanical Prosthetic Heart Valves: Insights from the Nationwide PLECTRUM Study

“…Few previous studies investigated potential differences in patients treated with different VKAs. A study including 498 patients with various indications of anticoagulant therapy (AF in 70% of cases) showed that acenocoumarol may be associated with a lower TiTR and a higher international normalized ratio (INR) variability, which improved after switching to phenprocoumon [ 8 ].…”

The Immediate Effect of COVID-19 Vaccination on Anticoagulation Control in Patients Using Vitamin K Antagonists

“…Furthermore, we stratified by type of VKA (acenocoumarol or phenprocoumon), because phenprocoumon is associated with better anticoagulation control. 22 Finally, we stratified by therapeutic range, as anticoagulation control is higher in the standard intensity group than in the high-intensity group. 23 All statistical analyses were performed with IBM SPSS statistics version 25.…”

The effect of COVID-19 vaccination on anticoagulation stability in adolescents and young adults using vitamin K antagonists

“…In addition, a similar analysis was done using two subsequent INRs four months before COVID-19 vaccination. Similarly, we stratified by type of VKA (acenocoumarol or phenprocoumon), because phenprocoumon is associated with better anticoagulation control as it has a longer half-live compared to acenocoumarol [ 28 ]. Finally, a subgroup analysis was performed by excluding AYAs who received a surgical intervention, had been hospitalized or started or ceased any medication interacting with VKA in the three months before and after COVID-19 vaccination.…”