Oral anticoagulation use by patients with atrial fibrillation in Germany. Adherence to guidelines, causes of anticoagulation under-use and its clinical outcomes, based on claims-data of 183,448 patients

Thromb Haemost. 2012 Jun;107(6):1053-65. doi: 10.1160/TH11-11-0768. Epub 2012 Mar 8.


Atrial fibrillation (AF) is the most common significant cardiac rhythm disorder. Oral anticoagulation (OAC) is recommended by guidelines in the presence of a moderate to high risk of stroke. Based on an analysis of claims-based data, the aim of this contribution is to quantify the stroke-risk dependent OAC utilisation profile of German AF patients as well as the possible causes and the associated clinical outcomes of OAC under-use. Our data set was derived from two large mandatory German medical insurance funds. Risk stratification of patients was based on the CHADS2-score and the CHA2DS2-VASc-score. Two different scenarios were constructed to deal with factors potentially disfavouring OAC use. Causes of OAC under-use and its clinical consequences were analysed using multivariate analysis. Observation year was 2008. A total of 183,448 AF patients met the inclusion criteria. This represents an AF prevalence of 2.21%. The average CHADS2-score was 2.8 (CHA2DS2-VASc-score: 4.3). On between 40.5 and 48.7% of the observed patient-days, there was no antithrombotic protection by OAC, other anticoagulants or aspirin. Older female patients with a high number of comorbidities had a higher risk of OAC under-use. Patients who had already experienced a thromboembolic event had a lower risk of OAC under-use. In the observation year, 3,367 patients experienced a stroke (incidence rate 1.8%). In our multi-level Poisson random effects estimate, OAC use decreases the stroke rate by almost 80% (IRR 0.236). In conclusion, OAC under-use is widespread in the German market. It is associated with severe clinical consequences.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Oral
  • Aged
  • Anticoagulants / administration & dosage*
  • Anticoagulants / adverse effects
  • Atrial Fibrillation / drug therapy*
  • Atrial Fibrillation / epidemiology
  • Drug Utilization / statistics & numerical data
  • Female
  • Germany / epidemiology
  • Guideline Adherence / statistics & numerical data*
  • Hemorrhage / chemically induced
  • Humans
  • Logistic Models
  • Male
  • Multivariate Analysis
  • Odds Ratio
  • Practice Guidelines as Topic*
  • Practice Patterns, Physicians' / statistics & numerical data*
  • Risk Assessment
  • Risk Factors
  • Stroke / epidemiology
  • Stroke / prevention & control*
  • Thromboembolism / epidemiology
  • Thromboembolism / prevention & control*


  • Anticoagulants