Primary prevention of arterial thromboembolism in non-rheumatic atrial fibrillation in primary care: randomised controlled trial comparing two intensities of coumarin with aspirin.

Department of General Practice, University of Maastricht, 6200 MD Maastricht, Netherlands.
BMJ Clinical Research (Impact Factor: 14.09). 11/1999; 319(7215):958-64. DOI: 10.1136/bmj.319.7215.958
Source: PubMed

ABSTRACT To investigate the effectiveness of aspirin and coumarin in preventing thromboembolism in patients with non-rheumatic atrial fibrillation in general practice.
Randomised controlled trial.
729 patients aged >/=60 years with atrial fibrillation, recruited in general practice, who had no established indication for coumarin. Mean age was 75 years and mean follow up 2. 7 years.
Primary care in the Netherlands.
Patients eligible for standard intensity coumarin (international normalised ratio 2.5-3.5) were randomly assigned to standard anticoagulation, very low intensity coumarin (international normalised ratio 1.1-1.6), or aspirin (150 mg/day) (stratum 1). Patients ineligible for standard anticoagulation were randomly assigned to low anticoagulation or aspirin (stratum 2).
Stroke, systemic embolism, major haemorrhage, and vascular death.
108 primary events occurred (annual event rate 5.5%), including 13 major haemorrhages (0.7% a year). The hazard ratio was 0.91 (0.61 to 1.36) for low anticoagulation versus aspirin and 0.78 (0.34 to 1.81) for standard anticoagulation versus aspirin. Non-vascular death was less common in the low anticoagulation group than in the aspirin group (0.41, 0.20 to 0.82). There was no significant difference between the treatment groups in bleeding incidence. High systolic and low diastolic blood pressure and age were independent prognostic factors.
In a general practice population (without established indications for coumarin) neither low nor standard intensity anticoagulation is better than aspirin in preventing primary outcome events. Aspirin may therefore be the first choice in patients with atrial fibrillation in general practice.

  • [Show abstract] [Hide abstract]
    ABSTRACT: Atrial fibrillation and arterial hypertension represent two common clinical conditions that frequently coexist, especially in older individuals, and are associated with increased risk of stroke. Antihypertensive therapy reduces the risk of stroke by approximately 40%. It has been observed that stroke rates were reduced by 10% for every 2-mmHg reduction of blood pressure. Antithrombotic therapy reduces significantly the risk for ischemic stroke in patients with atrial fibrillation at the expense of increased risk of intracranial bleeding. The importance of hypertension in patients with atrial fibrillation is recognized by its inclusion both in the CHA2DS2-VASc (risk for stroke) and the HAS-BLED (Hypertension, Abnormal renal/liver function, Stroke, Bleeding history or predisposition, Labile international normalized ratio, Elderly, Drugs/alcohol concomitantly) scores (risk for bleeding) and the presence of hypertension alone is an indication to initiate antithrombotic treatment. However, blood pressure remains remarkably unappreciated in previous and recent atrial fibrillation trials. Very limited, if any, data are provided regarding blood pressure, including in-study and final blood pressure levels, blood pressure control, and concomitant antihypertensive medication. In contrast, several lines of evidence point toward a significant role of pre and in-treatment blood pressure for ischemic and hemorrhagic stroke in patients with atrial fibrillation as well as for the incidence of intracranial bleeding during antithrombotic treatment. We propose that regular blood pressure recording should be mandatory in all future studies with antithrombotic therapy, analyses based on final and in-study blood pressure values, hypertension control, and antihypertensive medication should be performed, and the outcome be adjusted for blood pressure-related variables.
    Journal of Hypertension 09/2013; · 4.22 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Atrial fibrillation (AF) is associated with a high incidence of strokes/thromboembolism. The CHADS2 score assigns points for several clinical variables to identify stroke risk. The CHA2DS2-VASC score uses the same variables but also incorporates age 65 to 74, female gender, and vascular disease in an effort to provide a more refined risk of stroke/thromboembolism. We aimed to examine oral anticoagulation (OAC) recommendations for a cohort of patients undergoing AF ablation depending upon whether thrombo-embolic risk was determined by the CHADS2 or CHA2DS2-VASC score.METHODS AND RESULTS: For 1411 patients we compared OAC recommendations for each of these risk stratification schemes to one of the three OAC strategies: (i) NO-OAC, (ii) CONSIDER-OAC, and (iii) DEFINITE-OAC. Compared with the CHADS2 score, the CHA2DS2-VASC score reduced NO-OAC from 40.3 to 21.8% and CONSIDER-OAC from 36.6 to 27.9% while increasing DEFINITE-OAC from 23.0 to 50.2% of patients. Age 65 to 74 and female gender accounted for 95.2% and vascular disease for only 4.8% of recommendations for more aggressive OAC using CHA2DS2-VASC. Most vascular disease occurred in patients with higher CHADS2 scores already recommended for DEFINITE-OAC (P < 0.0001). Reclassifying 30 females of age <65 with a CHA2DS2-VASC score of 1 to the NO-OAC group had minimal effect on the overall recommendations.CONCLUSION: Compared with the CHADS2 score, in our AF ablation population, the CHA2DS2-VASC score markedly increases the number of AF patients for whom OAC is recommended. It will be important to determine by randomized trials if this major paradigm shift to greater use of OAC using the CHA2DS2-VASC scoring improves patient outcomes.
    Europace 09/2013; · 2.77 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Atrial fibrillation (AF) patients frequently require anticoagulation with vitamin K antagonists (VKAs) to prevent thromboembolic events, but their use increases the risk of hemorrhage. We evaluated time spent in therapeutic range (TTR), proportion of international normalized ratio (INR) measurements in range (PINRR), adverse events in relation to INR, and predictors of INR control in AF patients using VKAs.
    Thrombosis journal. 01/2014; 12:14.

Full-text (2 Sources)

Available from
May 27, 2014