IJCS | Volume 32, Nº5, September/October 2019

451 Table 1 - Baseline clinical characteristics of elderly ACS patients who received 75 mg clopidogrel (group I) versus 300 - 600 mg clopidogrel (group II) in the sample studied Group I Group II p Age (mean) 80.2 + 4.3 80.5 + 4.7 0.728π Diabetes Mellitus (%) 46.5 24.4 0.01# SAH (%) 90.7 75.6 0.01# Smoking (%) 30.2 17.8 0.105# Positive FH for CAD (%) 8.5 6.7 0.693# Dislypidemia (%) 62 42.2 0.021# CI (%) 7.9 4.4 0.451# Previous CVA (%) 10.1 6.7 0.495# Previous AMI (%) 37.2 42.2 0.552# Previous SMR (%) 15.5 22.2 0.304# Previous TCA (%) 26.4 35.6 0.24# Hb (mg/dL) (mean) 14.6 + 1.9 13.2 + 1.7 < 0.001π Troponin peak (mean) (ng/dL) 11.8 + 5.9 8.0 + 7.2 < 0.001π Cr (mg/dL) (mean) 1.3 + 0.5 1.5 + 0.4 < 0.0001π SBP (mmHg) (mean) 134.2 + 29.4 133.0 + 27.2 0.104π LVEF (%) (mean) 52.3 + 19.9 51.8 + 18.7 0.09* STEMI (%) 11.6 26.7 0.016# ASA (%) 98.4 100 0.401# Beta-blockers (%) 51.2 40 0.197# GPI IIb/IIIa (%) 5.4 0 0.111# Enoxaparin (%) 74.4 71.1 0.665# Fibrinolytic (%) 2.3 0 0.302# Statins (%) 82.2 95.6 0.088# ACEi (%) 49.6 53.3 0.667# SBP: systolic blood pressure; SAH: systemic arterial hypertension; FH: family history; CAD: coronary artery disease; HF: heart failure; CVA: cerebral vascular accident; AMI: acute myocardial infarction; SMR: surgical myocardial revascularization; TCA: coronary angioplasty; Hb: hemoglobin; Cr: creatinine; LVEF: left ventricular ejection fraction; GPI: glycoprotein inhibitor; ACEi: Angiotensin- Converting Enzyme Inhibitor. #: Q-square test; *: Student's t-test; π: Mann-Whitney U test. Soeiro et al. Clopidogrel in elderly patients Int J Cardiovasc Sci. 2019;32(5):449-456 Original Article As for the incidence of hemorrhagic complications, the most frequent was hemorrhagic stroke (50% of cases), followed by femoral artery puncture (35%), epistaxis (10%) and hemarthrosis (5%). Major bleeding occurred in 45.5% of patients in group I and 44.4% in group II (p = 0.672). Mortality rate among patients who had any type of bleeding versus those who had no bleeding was 25%vs. 4.5% (p < 0.0001). Types of bleeding per group can be observed in Figure 1. The types of vascular accesses were also similar between the groups, with radial access being used in 48%of patients in group I and 51% in group II (p = 0.347). Discussion This study showed important data reproduced in the Brazilian population on a controversial issue in the literature. We reported higher reperfusion rates (especially percutaneous) and ACS with ST elevation in patients in group II, in a significant manner. In relation to bleeding, significant differences were observed, with a higher incidence in patients who received clopidogrel (300-mg to 600-mg loading dose). Furthermore, hemorrhagic stroke was the most prevalent bleeding disorder and the occurrence of any bleeding (major or minor) had an impact on higher in-hospital mortality rates. Nevertheless, in the comparison between groups I and II there were no differences regarding mortality and combined events. The current guidelines recommend the use of full treatment and loading dose of clopidogrel in patients aged over 75 years, without almost any distinction when compared to younger patients. The current guidelines of the American Heart Association, the European Society of Cardiology or the Brazilian Society of Cardiology, 3-8 suggest that the 600-mg loading dose is preferable in all patients undergoing PCI. The only exception, which contemplates the elderly, refers to patients aged over 75 years undergoing fibrinolytic therapy, for whom only the dose of 75 mg clopidogrel is recommended, with no additional loading dose. 3-8 However, until 2015, in Brazil, the guidelines recommended that only the 75-mg clopidogrel dose should be administered to all patients aged over 75 years, with no loading dose. 10 This recent change in the guidelines allowed for a retrospective analysis of data and the assessment of the safety of the use of clopidogrel in older patients undergoing invasive procedures, following the previous recommendation in contrast with the new recommendation, since fibrinolytics were used in less than 2% of cases. The most cautious recommendation concerning the elderly, which prevailed until 2015, came primarily from