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Published on: November 8, 2024
Resistance to clopidogrel: prevalence and associate variables.
Fabrício Braga da Silva1, Gustavo Luiz Gouvêa de Almeida Junior, Augusto Neno
1Casa de Saúde São José, Rio de Janeiro, Brasil. fabriciobraga@uol.com.br
Arquivos Brasileiros De Cardiologia
|November 28, 2012
Summary
High rates of clopidogrel resistance were observed in patients undergoing angioplasty, with elevated blood glucose and prior heart attack being key associated factors. Understanding this resistance is crucial for optimizing antiplatelet therapy.
Area of Science:
- Cardiology
- Pharmacology
- Clinical Medicine
Background:
- Dual antiplatelet therapy (DAPT) with aspirin (ASA) and clopidogrel is standard post-angioplasty.
- Clopidogrel resistance, or inadequate platelet aggregation inhibition, poses a clinical challenge.
- Prevalence and associated factors of clopidogrel resistance are not well-established in all populations.
Purpose of the Study:
- To determine the prevalence of clopidogrel resistance in patients undergoing coronary stent implantation.
- To identify clinical and biochemical variables associated with clopidogrel resistance.
Main Methods:
- A cross-sectional cohort study of 205 patients receiving ASA and clopidogrel post-elective angioplasty.
- Platelet aggregation measured via optical aggregometry using adenosine diphosphate (ADP).
- Logistic regression analysis used to identify associated variables.
Main Results:
- The prevalence of clopidogrel resistance was high at 38.5% (95% CI: 31.9 - 45.2%).
- Independent predictors of resistance included elevated blood glucose (OR=1.014), history of myocardial infarction (OR=2.320), and therapeutic response to ASA (OR=1.057).
Conclusions:
- A significant proportion of patients exhibit clopidogrel resistance.
- Glycemia, prior myocardial infarction, and ASA response are associated with resistance.
- Further research is needed, especially with the advent of new antiplatelet agents.
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