IJCS | Volume 32, Nº5, September/October 2019

DOI: 10.5935/2359-4802.20190031 449 ORIGINAL ARTICLE International Journal of Cardiovascular Sciences. 2019;32(5):449-456 Mailing Address: Alexandre de Matos Soeiro Rua João Moura, 870, apto 192b. Postal Code: 05412-002, Pinheiros, São Paulo, SP - Brazil. E-mail: alexandre.soeiro@bol.com.br Is There Safety in the Use of Clopidogrel Loading Dose in Patients Over 75 Years of Age with Acute Coronary Syndrome? Alexandre de Matos Soeir o, G uilherme Casal e, Maria Antonieta Albanez Albuquerque de Medeiros Lope s, Lucas Colombo Godo y, A line Siqueira Boss a, B runo Bisell i, T atiana de Carvalho Andreucci Torres Lea l, Maria Carolina Feres de Almeida Soeir o, C arlos V. Serrano Jr ., M úcio Tavares Oliveira J r. Unidade Clínica de Emergência - InCor - HCFMUSP - São Paulo, SP - Brazil Manuscript received January 07, 2018; revised manuscript August 28, 2018; accepted November 03, 2018. Abstract Background: There is limited evidence in the literature regarding the administration of clopidogrel to acute coronary syndrome (ACS) in patients over 75 years of age. Most studies excluded this age group, making the subject controversial due to the increased risk of bleeding in this population. Objective: This is a retrospective, unicentric, and observational study aimed at assessingwhether the administration of clopidogrel loading dose increases bleeding rates in patients over 75 years of age. Methods: Patients were divided into two groups: group I: 75 mg of clopidogrel; group II: 300-to 600-mg loading dose of clopidogrel. A total of 174 patients (129 in group I and 45 in group II) were included between May 2010 and May 2015. Statistical analysis: The primary outcome was bleeding (major and/or minor). The secondary outcome was combined events (cardiogenic shock, reinfarction, death, stroke and bleeding). The comparison between groups was performed through Q-square and T-test. The multivariate analysis was performed by logistic regression, being considered significant p < 0.05. Results: Comparisons between groups I and II showed differences in the prevalence of diabetes (46.5% vs. 24.4%, p = 0.01), arterial hypertension (90.7% vs. 75, p = 0.01), dyslipidemia (62% vs. 42.2%, p = 0.021), ST segment elevation (11.6% vs. 26.6%, p = 0.016) and coronary intervention percutaneous (16.5% vs. 62.2%, p < 0.0001), respectively. In the multivariate analysis, significant differences were observed between groups I and II in relation to the occurrence of bleeding (8.5% vs. 20%, OR = 0.173, 95% CI: 0.049 - 0.614, p = 0.007). Conclusion: The use of a loading dose of clopidogrel (≥ 300 mg) in the population over 75 years of age is associated with higher bleeding rates. (Int J Cardiovasc Sci. 2019;32(5):449-456) Keywords: Platelet Aggregation Inhibitors/therapeutic use; Acute Coronary Syndrome/complications; Aged; Hemorrhage; Treatment Outcome. Introduction Among the elderly population, only 40% of patients over 75 years of age receive reperfusion therapy in the United States. 1 Consistent with these numbers, a recent study in England found that older patients were incrementally less likely to receive invasive and medical therapy. 2 Current guidelines do not suggest any age-related limitations of medical or invasive therapy, stating that percutaneous coronary intervention (PCI) in acute coronary syndrome (ACS) is beneficial for elderly patients. 3-8 However, there is little evidence in the literature concerning the use of loading dose of clopidogrel in patients aged over 75 years with ACS. Most randomized studies have excluded this age group, and hence there is limited data available, which makes the subject controversial, due to increased bleeding risk in this population. 1 The description of these comparative data in Brazilian registries has not yet been documented.