Bleeding risk factors in chronic oral anticoagulation with acenocoumarol

Abstract

We studied major bleeding complications, death related to hemorrhage, and tried to identify predisposing factors for bleeding in outpatients treated with acenocoumarol. We evaluated 811 outpatients attending a specialized anticoagulant therapy unit. The intended INR range was 3.5-4.5 for mechanical heart valve replacement (N = 384) and 2.0-3.0 for other indications (N = 427). The variability of INR for the total follow-up and the 2 months before the hemorrhage was calculated. The total follow-up was 1,963.26 years with 27,321 control tests. We observed 47 major bleeding episodes, including 2 fatal (central nervous system hemorrhages), in 37 patients. 49.5% of the patients had underlying diseases. The rate of major and fatal hemorrhage was 2.39 and 0.10 episodes per 100 patients year, respectively. Hemorrhagic complications were more frequently observed in patients with a more intense intended range (8.2% in the INR 3.5-4.5 group vs. 1.5% in the 2.0-3.0 INR group). The risk of major bleeding increased in patients with an achieved INR higher than 6 and in those with higher INR variability during follow-up. The estimated probability of bleeding also increased with time: it was 0.102% at 78 months, and at the beginning of therapy it was 0.006% and 0.007% at 1 and 4 months, respectively. The intensity of anticoagulation and the deviation of the INR from the target are the most important risk factors for bleeding in patients taking acenocoumarol. Monitoring the variability of INR can help identifying patients predisposed to bleeding. However, the screening for underlying disease should always be performed. Am.

Polypharmacy is Associated with an Increased Risk of Bleeding in Elderly Patients with Venous Thromboembolism

“…4,5,7,8,35 While most studies found that the prescription of more than two to seven drugs 4,6-8 was significantly associated with bleeding, others did not. 33,35 In one retrospective study of 811 anticoagulated patients, of whom 74 % had mechanical heart valves or atrial fibrillation, patients who bled were not taking more medications than those who did not bleed. 35 However, the patients in this study were substantially younger than in our cohort and over 80 % received less than two co-medications.…”

“…Our findings are difficult to compare with the results of prior studies that used differing definitions for polypharmacy, 6,7,33 focused on other disease populations (e.g., patients with atrial fibrillation), [4][5][6][7][8][9]33,35 and included also patients aged < 65 years. 4,5,7,8,35 While most studies found that the prescription of more than two to seven drugs 4,6-8 was significantly associated with bleeding, others did not.…”

“…33,35 In one retrospective study of 811 anticoagulated patients, of whom 74 % had mechanical heart valves or atrial fibrillation, patients who bled were not taking more medications than those who did not bleed. 35 However, the patients in this study were substantially younger than in our cohort and over 80 % received less than two co-medications. Finally, in a prospective study of 4,093 patients aged ≥ 80 years, of whom 74 % received vitamin K antagonists for atrial fibrillation, the use of ≥ 3 co-medications did not significantly increase the risk of major bleeding.…”

Gestion péri-opératoire des patients traités par antithrombotiques en chirurgie orale. Argumentaire

“…Une valeur de l'INR supé-rieure à 6 est associée à une augmentation significative du risque d'hémorragie majeure spontanée [59]. Les patients ayant un INR cible élevé (au maximum entre 3,5 et 4,5) ont un risque d'hémorragie (mineure, majeure) spontanée plus élevé que ceux ayant un INR cible entre 2 et 3 [9,10].…”

“…Les patients ayant un INR cible élevé (au maximum entre 3,5 et 4,5) ont un risque d'hémorragie (mineure, majeure) spontanée plus élevé que ceux ayant un INR cible entre 2 et 3 [9,10]. En revanche, aucune corrélation n'a été trouvée entre le risque hémorragique et la molécule AVK prescrite ou la durée écoulée depuis le début du traitement [59]. [122].…”