Anticoagulation therapy in patients with stage 3 to 4 chronic kidney disease (CKD) appears protective but it also significantly increases the risk for hemorrhage and worsens anemia, according to new study findings.
To assess the relative risks and benefits of anticoagulation and antiplatelet therapies, a team from Gregorio Marañón General University Hospital in Madrid, Spain, examined the rates of hemorrhage, cardiovascular events, and mortality among 81 untreated, 91 anticoagulated (acenocoumarol and low molecular weight heparin), and 60 antiaggregated (acetylsalicylic acid or clopidogrel) outpatients.
At baseline, control patients had significantly higher serum hemoglobin and ferritin levels. Hemoglobin values were 13.7 vs 13.3 vs 12.7 g/dL and ferritin levels 170 vs 140 vs 105 μg/L, respectively. Per protocol, no one received erythropoiesis-stimulating agents.
Over 3 years, bleeding events occurred in 4 control, 23 anticoagulated, and 9 antiaggregated patients. Results published in Clinical Medicine showed that the risks for bleeding quadrupled with anticoagulation and nearly tripled with anti-aggregation, according to a Cox model adjusted for age, renal function, and hemoglobin levels. The researchers suggested than an optimal dose of anticoagulants that minimizes bleeding still needs to be identified.
The team also reported 64 cardiovascular events, including 21 atherosclerotic events (10 in the antiaggregation group, 8 in the control group, and 3 in the anticoagulation group). Anticoagulation appeared to offer “a protective effect,” reducing the risk for atherosclerotic events by more than 85%.
“Therefore, our results support the use of anticoagulation and not antiaggregation in the secondary prevention of atherothrombotic events in patients with CKD who are not on dialysis, although there is a greater risk of bleeding,” Ana García-Prieto, MD, and her colleagues stated. They added that use of anticoagulant treatment must be individualized according to a patient’s risk for hemorrhage and thrombosis.
In a discussion of study limitations, the authors noted that atrial fibrillation was the impetus for anticoagulation in 94.5% of anticoagulated patients compared with 28.3% of antiaggregated patients, and this may have influenced results. In addition, cardiovascular prognoses and medication type varied among patients.
García-Prieto A, Goicoechea M, Linares T, et al. Impact of anticoagulation and platelet antiaggregation in anemia and bleeding and atherosclerotic events in patients with stage 3 and 4 chronic kidney disease. Clin Med. doi:10.1016/j.medcli.2018.01.021