First, we would like to thank Alfaro-Lara et al for their consideration of the study conducted by our group (ANFAGAL), and their acknowledgment of the effort made by the researchers regarding sample selection. However, we would like to go into certain aspects mentioned in their letter.
We are not in favor of broadening the therapeutic range of vitamin K antagonists. The only interval that is safe and is supported by evidence is between 2 and 3.1 The failure to change the dose when a patient shows suboptimal control is referred to as “therapeutic inertia”, and under no circumstances should be used as an argument in a safety case.
With respect to self-monitoring, we wish to point out that it is not very widespread in Spain and that it is very costly. In fact, countries like Sweden that have reached extraordinarily high levels of control with the use of self-monitoring are modifying the management of oral anticoagulation in favor of a more extensive use of direct oral anticoagulants, which are more beneficial in terms of costs and safety than said model.2
Regarding adherence to therapy, we completely agree, but would like to call attention to different publications and analyses resulting from key clinical trials,3 registries of data from real-world clinical practice,4 or cohort studies designed to examine this aspect,5 all of which appear to indicate that adherence is greater with direct oral anticoagulants.
It is the responsibility of prescribing physicians and primary care teams to carry out an adequate follow-up of patients receiving anticoagulation therapy, preferably in a program for chronically ill patients, to ensure the implementation of an integrated approach to risk factors, individual lifestyle, and adherence to the prescribed drugs.
Finally, the agreement among three studies is not due to the variables influencing the primary endpoint; rather, it comes about because, in different sample populations, the authors identify the similar percentage of patients with suboptimal control of anticoagulation.