Harms of antiplatelet therapy may outweigh benefits in chronic kidney disease

Antiplatelet therapy may have uncertain benefits that could be outweighed by bleeding risk in patients with chronic kidney disease (CKD), according to a new study.


Researchers performed a systematic review and meta-analysis to determine how antiplatelet therapy affected cardiovascular events and mortality and bleeding rates in CKD patients. They searched the Embase and Cochrane databases through November 2011 to find 40 randomized trials in adult CKD patients that compared antiplatelet agents with standard care, no treatment, or placebo. Nine of the included trials reported on 9,969 patients with CKD who had acute coronary syndromes or were undergoing percutaneous coronary intervention; all of these data were post hoc analyses of CKD patients from larger trials. The remaining 31 trials reported on 11,701 CKD patients with stable cardiovascular disease or no cardiovascular disease. The study results were published in the March 20 Annals of Internal Medicine.

In the nine trials involving post hoc analyses, glycoprotein IIb/IIIa inhibitors or clopidogrel added to standard care increased serious bleeding compared with standard care alone, but had little or no effect on all-cause or cardiovascular mortality or myocardial infarction rates in patients with acute coronary syndromes. In the 31 trials of patients with CKD and stable or no cardiovascular disease, antiplatelet agents compared with placebo or no treatment protected against myocardial infarction but did not necessarily improve mortality rates and they increased rates of minor bleeding. All of these findings were based mainly on low-quality evidence.

The authors noted that their conclusions were based on trial-level rather than individual-patient data, that the available data overall were limited, and that the included trials were of different durations and used different definitions of bleeding outcomes, among other limitations. However, they concluded that the evidence supporting antiplatelet therapy in patients with CKD is of low quality. "Bleeding hazards and lack of clear efficacy in reducing cardiovascular morbidity and mortality need to be acknowledged when patients with CKD are being counseled about acute or long-term antiplatelet therapy," they wrote.