TY - JOUR
T1 - Bleeding in patients receiving vitamin K antagonists who would have been excluded from trials on which the indication for anticoagulation was based
AU - Levi, Marcel
AU - Hovingh, G. Kees
AU - Cannegieter, Suzanne C.
AU - Vermeulen, Marinus
AU - Büller, Harry R.
AU - Rosendaal, Frits R.
PY - 2008
Y1 - 2008
N2 - Vitamin K antagonists (VKAs) are effective antithrombotic agents and advocated in guidelines for the management of cardiovascular disease. However, in the trials underlying these guidelines, many patients were excluded. We performed a case-control study in 993 patients receiving VKAs, who required hospitalization for bleeding, and contrasted them to 993 matched control patients on VKAs, who were hospitalized for an infection. We analyzed whether patients and controls would have been eligible for the clinical trials on which their indication for anticoagulation was based, and estimated the risk of hemorrhage associated with exclusion criteria as applied in those trials. Approximately one quarter (23% [95% CI: 21%-26%]) of controls had one or more exclusion criteria for the trials, supporting the use of anticoagulation for their condition. Forty percent of patients presenting with bleeding had one or more exclusion criteria (95% CI: 37%-43%). Having one exclusion criterion resulted in a 2.9-fold increased risk of bleeding (95% CI: 2.2-3.9), and this risk increased sharply when more than one exclusion criterion was present. VKAs are often prescribed to patients who would not have qualified for clinical trials, and in these patients a careful consideration should be made regarding the expected efficacy and the risk of bleeding
AB - Vitamin K antagonists (VKAs) are effective antithrombotic agents and advocated in guidelines for the management of cardiovascular disease. However, in the trials underlying these guidelines, many patients were excluded. We performed a case-control study in 993 patients receiving VKAs, who required hospitalization for bleeding, and contrasted them to 993 matched control patients on VKAs, who were hospitalized for an infection. We analyzed whether patients and controls would have been eligible for the clinical trials on which their indication for anticoagulation was based, and estimated the risk of hemorrhage associated with exclusion criteria as applied in those trials. Approximately one quarter (23% [95% CI: 21%-26%]) of controls had one or more exclusion criteria for the trials, supporting the use of anticoagulation for their condition. Forty percent of patients presenting with bleeding had one or more exclusion criteria (95% CI: 37%-43%). Having one exclusion criterion resulted in a 2.9-fold increased risk of bleeding (95% CI: 2.2-3.9), and this risk increased sharply when more than one exclusion criterion was present. VKAs are often prescribed to patients who would not have qualified for clinical trials, and in these patients a careful consideration should be made regarding the expected efficacy and the risk of bleeding
U2 - https://doi.org/10.1182/blood-2007-11-123711
DO - https://doi.org/10.1182/blood-2007-11-123711
M3 - Article
C2 - 18316627
SN - 0006-4971
VL - 111
SP - 4471
EP - 4476
JO - Blood
JF - Blood
IS - 9
ER -