gms | German Medical Science

Background: An optimal adjustment In Patients with atrial fibrillation is crucial to decrease their mortality. So far there have been only few substances for their treatment, VKA as standard-mediaction and heparines with measurable, but subordinated amount. Marcumar is characterized by its small therapeutic range and plenty of interactions with other drugs and food, which makes an optimal adjustment difficult. A couple of years ago the first NOAC, characterized by easier handling compared to VKA, was approved. Now, years after the first approval of the first NOAC, there is still only little evidence proving a general, long-term advantage of patients treated with NOACs compared to patients treated with VKA in an optimal adjustment. Non the less NOACs cover a large range of prescriptions in this area. But especially Patients not taking their medication as prescribed/ not receiving the appropriate dosage/ range of tablets matching their individual needs, are at high risk of a lack of efficient protection. Advertisements spread the thesis “People are safer taking NOAC rather than VKA due to better compliance due to easier handling” among practitioners. The article “Adhärenz zu den neuen Antikoagulanzien (NOAK) am Beispiel Dabigatran” (Arzneimittelbrief Nr. 6 2015) draws new attention to this topic and provokes us taking a closer look at the data.

Materials and Methods: We analyzed prescriptions of patients insured with AOK in Westphalia-Lippe receiving a NOAC (included ATC: B01AE07 dabigatran, B01AF01 rivaroxaban, B01AF02 apixaban) while also having a secured diagnosis of atrial fibrillation (ICD I48.-) at any time in 2014. These patients might have also received VKA or/ and Heparin (included ATC: B01AA03/04, B01AB) at any time in 2014. The first included prescription of must have been before 05.07.2014 (31.12.14-180days), and the patient must have received at least 2 prescriptions with 180 days inbetween, to make sure the patient is matching the criteria of a long-term-treatment as it is expected in patients with atrial fibrillation. We checked if the prescribed amount of medication (first to last but one prescription) per patient could cover the period of days from first to last prescription appropriately. We compared the amount of coverd days by counting counting units, DDD (defined by “Anatomisch-therapeutisch-chemische Klassifikation mit Tagesdosen Amtliche Fassung des ATC-Index mit DDD-Angaben für Deutschland im Jahr 2015” as 220 mg dabigatran, 10 mg rivaroxaban and 5 mg apixaban) and Dt (Dt = recommended daily intake for patients with atrial fibrillation defined by Fachinformation; this made one Dt 300 mg dabigatran, 20 mg rivaroxaban and 10 mg apixaban; no Dt-adoptions were made for the dosage of VKA/ Heparin.

Results: Often VKA-criticism is made due to deviation between actual value and index value, which makes people judge this therapy as insufficient. This negative monitoring appears to be a positive aspect regarding our first findings. An uninterrupted, continuous, dosage-adequate therapy in the considered time is obviously not given to the majority of included patients. This deficient supply in patients with atrial fibrillation seems to be not regarded within the doctor-patient-relationship.

Further investigations, regarding more details, are intended to be finished by the end of October.

Conclusion: So far the first results are very shuttering, showing an inadequate therapy in general. A next step including a second dosage adjustment for patients with kidney-insufficiency or/ and a look at the times spend in hospital influencing the amount of days to be covered, might be usefull.