Abstract 15529: Correlations Between Estimated Glomerular Filtration Rate, Major Bleeding and Thromboembolic Complications in Patients on Anticoagulation Treatment with Warfarin
Aims: Estimated glomerular filtration rate (eGFR) is an established risk factor for bleeding but has not previously been associated with bleeding risk in patients on anticoagulation treatment with warfarin in the presence of high levels of individual time in therapeutic range (iTTR). In this paper we report prospective data on correlations between iTTR, eGFR, major bleeding and thrombo-embolic complications in all patients on anticoagulation treatment with warfarin in one anticoagulation center in AuriculA, the Swedish national quality registry for atrial fibrillation and anticoagulation.
Methods and Results: A total of 75 bleedings and 51 thrombo-embolic events in 3536 patients were registered during a total of 2875 treatment years. Mean iTTR was 76.1% for the individual target intervals. A correlation with age, percentage of time >3.0 INR and bleeding events (p<0.001) was seen. Data on eGFR in 3349 patients demonstrated a prevalence of eGFR<45 of 52% in patients aged ≥75 years with major bleeding and an increased risk of bleeding was seen with lower eGFR levels. No correlation between eGFR and thrombo-embolic events was seen.
Conclusion: Our data indicate that in anticoagulation centers with tight anticoagulation control measured by iTTR, elderly patients ≥ 75 years have similar risks for major bleeding as younger patients if consideration is given to renal function. eGFR levels <30 ml/min/1.73m2 are associated with high risks of bleeding in the elderly on treatment with warfarin. This is of high relevance in the upcoming era of new anticoagulants and we advise extra caution, taken to account the additional risk of drug accumulation in anticoagulants eliminated by renal route.
- © 2011 by American Heart Association, Inc.