Age-dependency of prescribing patterns of oral anticoagulant drugs in Austria during 2011-2014.

Direct oral anticoagulants (DOACs) have been introduced within the last years as alternative to vitamin K antagonists (VKAs) as oral anticoagulant drugs (OAC). The mean/median age of the patients included in DOAC-investigating trials was 70-72 years. The age-pattern of patients to whom DOAC are prescribed in clinical settings is largely unknown. Thus, aim of the study was to assess the age-pattern of patients who received OAC in the years 2011-2014 in Austria. The data analysis refers to the accounting data of the 13 major health insurance funds, covering >97 % of the Austrian population. The number of patients who received OAC in 2011-2014 increased by 43 % (182,464-261,347). Patients who received DOACs increased nearly fivefold (20,927-96,247), whereas patients who received VKAs increased by only 2 % (161,537-165,100). In 2011, the age of patients receiving VKAs was higher than DOACs (72 vs. 68 years), whereas in 2014, the age of the patients receiving VKAs was lower than DOACs (73 vs. 74 years). The proportion of patients ≥80 years receiving VKAs declined from 26 to 21 % of all OAC, receiving DOACs increased from 1 to 12 %. Among nonagenarians, the proportion of patients receiving VKAs remained 2 % (3316-5858), whereas the proportion of patients receiving DOACs increased 40-fold (91-4296). DOACs are prescribed to patients ≥80 years, although there are is a lack of data about efficacy and safety. There is an urgent need for data about this patient group. Since a randomized trial is rather unlikely in this specific age group we suggest subgroup analyses about octo-and nonagenarians, in case they have been included in previously completed or still ongoing trials or registries for OAC.

[Pulmonary Embolism Despite Rivaroxaban in an Obese Patient]. / Pulmonalembolie trotz Rivaroxaban bei einer adipösen Patientin.

Introduction Rivaroxaban, an oral factor Xa inhibitor, is approved for therapy of venous thromboembolism. It is unclear whether the standard dose for patients with a body mass index (BMI) > 40 kg/m2 is sufficient. History The 45-year-old patient was admitted because of increasing respiratory distress. She had a history of pulmonary embolism 30 months before the admission, a factor V Leiden mutation and several hospitalisations due to dermatomycoses. The patient briefly took phenprocoumon which was changed to 20 mg rivaroxaban due to a lack of adherence. Six months before admission, the patient paused the rivaroxaban therapy because of dental surgery and suffered a recurrent pulmonary embolism. Findings and Diagnosis The patient presented with increasing difficulty of breathing, morbid obesity with a BMI of 59.3 kg/m2 and intertrigo of the lower extremities. The ECG showed a right axis deviation, a pulmonary P-wave and an incomplete right bundle branch block. Computed tomography showed pulmonary embolisms of the left lower lobe. The pulmonary artery was dilated, and the right atrium was enlarged. Venous thrombosis of the lower limb could not be certainly ruled out. The D-dimer was elevated with 5.895 mg/L (normal value up to 169 mg/L) and NT-pro-BNP was elevated at 5.580 ng/L (normal value up to 0.5 ng/L). Sixteen hours after the onset of symptoms, 22 hours after the last dose, the serum rivaroxaban level was 137 ng/ml. According to manufacturers, the therapeutic range of rivaroxaban after 2 - 4 hours is 22 - 535 ng/ml, and after 24 hours 6 - 239 ng/ml. Therapy and course After initiation of a therapy with low-molecular weight heparin and subsequent oral anticoagulation with phenprocoumon, the symptoms decreased. Conclusions It is highly probable that the pulmonary embolism occurred at a time when the rivaroxaban level was in the therapeutic range. Since there are only few data about safety and efficacy of rivaroxaban and other non-vitamin K-oral anticoagulants (NOACs) in severely obese patients, the recommendations of the "International Society for Thrombosis and Haemostasis" should be followed: Rivaroxaban and other NOACs should not be used in patients with a BMI > 40 kg/m2 or weight > 120 kg, since only few data on this patient group are available. If NOACs are necessary in these patients, serum concentrations of NOACs should be measured.