INTRODUCTION

While a 600 mg loading dose (LD) of clopidogrel has demonstrated superior inhibition of platelet function compared to 300 mg LD, the clinical evidence supporting this superiority is limited. The debate centers on whether higher clopidogrel LD regimen in percutaneous coronary intervention (PCI) outperforms the standard 300 mg LD, with potential benefits being more pronounced in higher-risk patients. Balancing enhanced platelet inhibition to reduce ischemic events against the associated risk of increased bleeding remains a critical consideration in determining the optimal loading dose of clopidogrel for patients with ischemic heart disease.

A systematic literature search for randomized clinical trials (RCTs) was performed comparing 600 mg with 300 mg LD of clopidogrel using PubMed, MEDLINE, Embase, Cochrane, Clinicaltrials.gov and HerdinPH. Studies included those between 2010 and 2023 involving human subjects. The primary efficacy endpoint was a 1-month rate of major adverse cardiac event (MACE) and the primary safety outcome was bleeding adverse effects.

Nine RCTs involving 29,827 patients were included in the efficacy analysis. Mean duration of follow-up was 30 days. Only eight studies were eligible for safety analysis. Compared with standard LD clopidogrel, high LD significantly reduced the incidence of overall MACE (OR: 0.82, 95% CI: 0.74-0.91, p = 0.0002), nonfatal myocardial infarction (OR: 0.56; 95% CI: 0.32-0.99, p = 0.15) and target vessel revascularization (OR: 0.63; 95% CI: 0.41-0.95, p = 0.03), without significant difference in terms of cardiac death (OR: 0.89; 95% CI: 0.76-1.04, p = 0.15) and stroke (OR: 0.92; 95% CI: 0.67-1.26, p = 0.61). However, major bleeding risk was higher in the 600 mg LD (1.9%; 261/13288) compared with 300 mg LD (2.4%; 328/13242) [OR: 1.27; 95% CI: 1.08-1.49, p = 0.005] without significant difference in minor bleeding (OR: 1.05; 95% CI: 0.94-1.17, p = 0.35).

The administration of 600 mg clopidogrel LD reduces the overall risk of MACE with associated increased risk of major bleeding.

Background: Antiplatelet resistance is one factor that contributes to stroke recurrence among patients with noncardioembolic ischemic strokes. Objectives: This paper aims to describe the prevalence of aspirin and clopidogrel resistance, along with frequency of statin, NSAID and proton pump inhibitor use among our cohort of stroke patients. Method. This is a single-center cross-sectional review that included all adult patients with recurrent noncardioembolic ischemic stroke admitted in a tertiary hospital between January 2019 and June 2023. Results: A total of 1,374 patients were admitted for ischemic stroke from January 2019 to June 2023. Among these, 155 (11.28%) were recurrent noncardioembolic ischemic strokes. Prevalence of aspirin and clopidogrel resistance were 25% and 32.7%, respectively. Clinical profiles of those in the resistant group were comparable with those in the nonresistant group. None of the patients taking aspirin had concomitant use of nonsteroidal antiinflammatory drugs. Only 2 of the patients who were resistant to clopidogrel were on proton pump inhibitors. More than half of the patients both in the resistant and the nonresistant groups were on statin. The study had a small sample size and hence it was not enough to establish causal relationship between factors and antiplatelet resistance. Conclusion More patients were resistant to clopidogrel than to aspirin. Further studies with a bigger sample size are recommended to explore factors that contribute to antiplatelet resistance in Filipino patients.
Aspirin ; Clopidogrel ; Ischemic Stroke ; Tertiary Care Centers

Objective To explore the risk factors of clopidogrel resistance (CR) in the elderly patients with atherosclerotic cardiovascular disease and to provide evidence for the antiplatelet therapy. Methods A total of 223 elderly patients (≥80 years old) with atherosclerotic cardiovascular disease treated in the Department of Geriatrics in the Peking University People's Hospital from January 18,2013 to November 30,2019 and meeting the inclusion criteria were enrolled in this study.The clinical data and laboratory test results were collected,including clinical disease,drug use,physical examination,complete blood cell analysis,biochemical indicators,and thromboelastogram (TEG).The rate of platelet inhibition induced by adenosine diphosphate was calculated according to the TEG.We assigned the patients into a CR group (n=84) and a control group (n=139) to analyze the incidence and influence factors of CR in the elderly patients with atherosclerotic cardiovascular disease. Results The incidence of CR was 37.7% in the elderly patients with atherosclerotic cardiovascular disease.The CR group had lower hemoglobin (t=3.533,P=0.001) and higher hypertension prevalence rate (χ²=6.581,P=0.006),proportion of multiple drugs (χ²=3.332,P=0.048),body mass index (BMI) (t=-2.181,P=0.030),total cholesterol (t=-2.264,P=0.025),triglycerides (Z=-2.937,P=0.003),low-density lipoprotein cholesterol (LDL-C) (t=-2.347,P=0.020),and proportion of women (χ²=5.562,P=0.014) than the control group.The results of multivariate Logistic regression showed that hemoglobin (OR=0.962,P<0.001),BMI (OR=1.154,P=0.003),and LDL-C (OR=1.688,P=0.018) were the factors influencing CR in the elderly patients with atherosclerotic cardiovascular disease. Conclusion Hemoglobin,BMI,and LDL-C may be independent factors associated with the occurrence of CR in the elderly patients with atherosclerotic cardiovascular disease.
Aged ; Aged, 80 and over ; Female ; Humans ; Atherosclerosis ; Cardiovascular Diseases ; Cholesterol, LDL ; Clopidogrel/therapeutic use* ; Risk Factors

In this study, we reported a young male patient with acute chest pain who was diagnosed as myocardial infarction. The regular medication was performed following coronary intervention. Under such condition, this patient had 3 times myocardial infarction within a half month. The laboratory results showed that there might be a state of hypercoagulability. Aspirin combined with clopidogrel and other treatment were administrated. Meanwhile, the examination demonstrated that there was aspirin-resistant in the patient. The antiplatelet drug and extended anticoagulation therapy were carried out. There was no further myocardial infarction, and no coronary arteries stenosis was found in the re-examination angiography. Aspirin resistance and hypercoagulability should be considered when patients occurred the repeated myocardial infarction after regular medication and coronary intervention. Replacement of the antiplatelet treatment or combination with anticoagulant therapy is necessary in similar patient to avoid the sever consequence.
Aspirin/therapeutic use* ; Clopidogrel/therapeutic use* ; Drug Therapy, Combination ; Humans ; Male ; Myocardial Infarction/drug therapy* ; Percutaneous Coronary Intervention ; Platelet Aggregation Inhibitors/therapeutic use* ; Thrombophilia/drug therapy* ; Treatment Outcome

Objective: To assess the prevalence, pattern and outcome of multimorbidity in elderly patients with acute coronary syndrome (ACS). Methods: Secondary analysis was performed based on the data from the BleeMACS registry, which was conducted between 2003 and 2014. We stratified elderly patients (≥65 years) according to their multimorbidity. Multimorbidity was defined as two or more chronic diseases in the same individual. Kaplan-Meier methods were used to estimate 1 year event rates for each endpoint, and comparisons between the study groups were performed using the log-rank test. The primary endpoint was net adverse clinical events (NACE), which is a composite of all-cause mortality, myocardial infarction, or bleeding. Results: Of 7 120 evaluable patients, 6 391 (89.8%) were with morbidity (1 594 with 1, 2 156 with 2, and 2 641 with ≥3 morbidity). Patients with morbidity were older, percent of female sex and non-ST-elevation acute coronary syndromes and implantation rate with drug-eluting stents and blood creatine level were higher compared to patients without morbidity. Compared with the patients without morbidity, the proportion of participants with oral anticoagulant increased in proportion to increased number of morbidities (5.8% vs. 6.4% with 1 morbidity, 7.3% with 2 morbidities, 9.0% with ≥3 morbidities, P trend<0.01) and the proportion of participants with clopidogrel prescription decreased in proportion to increased number of morbidity (91.9% vs. 89.7% with 1 morbidity, 87.9% with 2 morbidities, 88.6% with ≥3 morbidities, P trend = 0.01). During 1 year follow-up, compared with those with no morbidity, the hazard ratio (HR) and 95% confidence interval (CI) of risk of NACE for those with 1, 2, and ≥ 3 morbidities was 1.18 (0.86-1.64), 1.49 (1.10-2.02), and 2.74 (2.06-3.66), respectively (P < 0.01). Multimorbidity was not associated with an increased risk of bleeding of various organs (P>0.05). Conclusion: Multimorbidity is common in elderly patients with ACS. These patients might benefit from coordinated and integrated multimorbidity management by multidisciplinary teams.
Acute Coronary Syndrome/epidemiology* ; Aged ; Clopidogrel ; Female ; Hemorrhage ; Humans ; Multimorbidity ; Percutaneous Coronary Intervention/methods* ; Platelet Aggregation Inhibitors/adverse effects* ; Registries ; Treatment Outcome

Objective: To compare the efficacy and safety between indobufen and aspirin in the prevention of restenosis of bridge vessels at 1 year after off-pump coronary artery bypass grafting. Methods: This study was a prospective cohort study. We selected 152 patients who received coronary artery bypass grafting in Beijing Anzhen Hospital from December 2016 to December 2018. Patients were divided into the indobufen group and the aspirin group. Patients in the aspirin group were treated with aspirin and clopidogrel, and patients in the indobufen group were treated with indobufen and clopidogrel. During the 1-year follow-up, the rate of restenosis of saphenous vein bridge and internal mammary artery bridge, the rate of adverse cardiac events and adverse reactions were compared between the two groups. The levels of fibrinogen (FIB), D-dimer (D-D), thrombomodulin (TM) and thrombin-activatable fibrinolysis inhibitor (TAFI) were compared before and after antiplatelet therapy. Results: There were 76 cases in the indobufen group, including 57 males (75.0%), aged (60.3±6.6) years. There were 76 cases in the aspirin group, including 62 males (81.6%), aged (59.7±7.2) years. Baseline data were comparable between the two groups (P>0.05). During the follow-up, 3 cases were lost to follow up. Follow-up was completed in 74 patients in the indobufen group and 75 in the aspirin group. A total of 268 bridging vessels were grafted in the indobufen group and 272 in the aspirin group. One year after surgery, the patency rates of great saphenous vein bridge and internal mammary artery bridge were 94.5% (189/200) and 97.1% (66/68) in the indobuphen group, and 91.3% (189/207) and 96.9% (63/65) in the aspirin group, respectively. There was no significant difference in patency rate of great saphenous vein bridge and internal mammary artery bridge between the two groups (χ²=0.282, 0.345, P>0.05). The total incidence of adverse cardiac events was 5.4% (4/74) in the indobufen group and 6.7% (5/75) in the aspirin group (χ²=0.126, P>0.05). The overall incidence of gastrointestinal adverse reactions was significantly lower in the indobufen group than in the aspirin group (4.1% (3/74) vs. 13.3% (10/75), χ²=4.547, P<0.05). The levels of FIB, D-D, TM and TAFI in the two groups were lower than those before surgery (P<0.05), and there was no statistical significance between the two groups at baseline and post-operation (P>0.05). Conclusion: The efficacy of indobufen combined with clopidogrel in the prevention of 1-year restenosis after coronary artery bypass graft is similar to that of aspirin combined with clopidogrel, but the incidence of adverse reactions is lower, and the safety is higher in patients treated with indobufen combined with clopidogrel compared to aspirin combined with clopidogrel strategy.
Aspirin/therapeutic use* ; Clopidogrel/therapeutic use* ; Coronary Artery Bypass/adverse effects* ; Drug Therapy, Combination ; Humans ; Isoindoles ; Male ; Phenylbutyrates ; Platelet Aggregation Inhibitors/therapeutic use* ; Prospective Studies ; Treatment Outcome

Objective: Due to genetic factors might increase the risk of depression, this study investigated the genetic risk factors of depression in Chinese Han population by analyzing the association between 13 candidate genes and depression. Methods: 439 depression patients and 464 healthy controls were included in this case-control study. Case group consisted of 158 males and 281 females, aged (29.84±14.91) years old, who were hospitalized in three departments of the affiliated Brain Hospital of Guangzhou Medical University including Affective Disorders Department, Adult Psychiatry Department and Geriatrics Department, from February 2020 to September 2021. The control group consisted of 196 males and 268 females, aged (30.65±12.63) years old. 20 loci of 13 candidate genes in all subjects were detected by MALDI-TOF mass spectrometry. Age difference was compared using the student's t-test, the distributions of gender and genotype were analyzed with Pearson's Chi-square test. The analyses of Hardy-Weinberg equilibrium, allele frequency and the genetic association of depression were conducted using the corresponding programs in PLINK software. Results: PLINK analysis showed that SCN2A rs17183814, ABCB1 rs1045642, CYP2C19*3 rs4986893 and NAT2*5A rs1799929 were associated with depression before Bonferroni correction (χ²=10.340, P=0.001; χ²=11.010, P=0.001; χ²=9.781, P=0.002; χ²=4.481, P=0.034). The frequencies of minor alleles of above loci in the control group were 12.07%, 43.64%, 2.59% and 3.88%, respectively. The frequencies of minor alleles of loci mentioned above in the case group were 17.43%, 35.99%, 5.47% and 6.04%, respectively. OR values were 1.538, 0.726, 2.178 and 1.592, respectively. After 1 000 000 permutation tests using Max(T) permutation procedure, the four loci were still statistically significant, the empirical P-value were 0.002, 0.001, 0.003 and 0.042, respectively. However, only three loci including SCN2A rs17183814, ABCB1 rs1045642 and CYP2C19 rs4986893 had statistical significance after Bonferroni correction, the adjusted P-value were 0.026, 0.018 and 0.035, respectively. Conclusion: SCN2A rs17183814, ABCB1 rs1045642 and CYP2C19*3 rs4986893 were associated with depression's susceptibility in Chinese Han population. The A allele of SCN2A rs17183814 and CYP2C19*3 rs4986893 were risk factors for depression, while the T allele of ABCB1 rs1045642 was a protective factor for depression.
ATP Binding Cassette Transporter, Subfamily B/genetics* ; Adolescent ; Adult ; Alleles ; Arylamine N-Acetyltransferase/genetics* ; Case-Control Studies ; Clopidogrel ; Cytochrome P-450 CYP2C19/genetics* ; Depressive Disorder, Major/genetics* ; Female ; Gene Frequency ; Genetic Predisposition to Disease ; Genotype ; Humans ; Male ; NAV1.2 Voltage-Gated Sodium Channel ; Polymorphism, Single Nucleotide ; Young Adult

BACKGROUND: High on-clopidogrel platelet reactivity could be partially explained by loss-of-function alleles of CYP2C19, the enzyme that converts clopidogrel into its active form. Shexiang Tongxin Dropping Pill (STDP) is a traditional Chinese medicine to treat angina pectoris. STDP has been shown to improve blood flow in patients with slow coronary flow and attenuate atherosclerosis in apolipoprotein E-deficient mice. However, whether STDP can affect platelet function remains unknown. OBJECTIVE: The purpose of this study is to examine the potential effects of STDP on platelet function in patients undergoing percutaneous coronary intervention (PCI) for unstable angina. The interaction between the effects of STDP with polymorphisms of CYP2C19 was also investigated. DESIGN, PARTICIPANTS AND INTERVENTION: This was a single-center, randomized controlled trial in patients undergoing elective PCI for unstable angina. Eligible subjects were randomized to receive STDP (210 mg per day) plus dual antiplatelet therapy (DAPT) with clopidogrel and aspirin or DAPT alone. MAIN OUTCOME MEASURES: The primary outcome was platelet function, reflected by adenosine diphosphate (ADP)-induced platelet aggregation and platelet microparticles (PMPs). The secondary outcomes were major adverse cardiovascular events (MACEs) including recurrent ischemia or myocardial infarction, repeat PCI and cardiac death; blood biomarkers for myocardial injury including creatine kinase-MB isoenzyme (CK-MB) and high-sensitive troponin I (hsTnI); and biomarkers for inflammation including intercellular cell adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), monocyte chemoattractant protein-1 (MCP-1) and galectin-3. RESULTS: A total of 118 subjects (mean age: [66.8 ± 8.9] years; male: 59.8%) were included into analysis: 58 in the control group and 60 in the STDP group. CYP2C19 genotype distribution was comparable between the 2 groups. In comparison to the control group, the STDP group had significantly lower CK-MB (P < 0.05) but similar hsTnI (P > 0.05) at 24 h after PCI, lower ICAM-1, VCAM-1, MCP-1 and galectin-3 at 3 months (all P < 0.05) but not at 7 days after PCI (P > 0.05). At 3 months, the STDP group had lower PMP number ([42.9 ± 37.3] vs. [67.8 ± 53.1] counts/μL in the control group, P = 0.05). Subgroup analysis showed that STDP increased percentage inhibition of ADP-induced platelet aggregation only in slow metabolizers (66.0% ± 20.8% in STDP group vs. 36.0% ± 28.1% in the control group, P < 0.05), but not in intermediate or fast metabolizers. The rate of MACEs during the 3-month follow-up did not differ between the two groups. CONCLUSION: STDP produced antiplatelet, anti-inflammatory and cardioprotective effects. Subgroup analysis indicated that STDP inhibited residual platelet reactivity in slow metabolizers only. TRIAL REGISTRATION This study was registered on www.chictr.org.cn: ChiCTR-IPR-16009785.
Adenosine Diphosphate ; Angina, Unstable/chemically induced* ; Animals ; Biomarkers ; Clopidogrel ; Cytochrome P-450 CYP2C19/genetics* ; Drugs, Chinese Herbal ; Galectin 3 ; Humans ; Intercellular Adhesion Molecule-1 ; Male ; Mice ; Percutaneous Coronary Intervention/adverse effects* ; Platelet Aggregation Inhibitors/adverse effects* ; Vascular Cell Adhesion Molecule-1/genetics*

BACKGROUND: Geriatric hip fracture patients receiving clopidogrel are a surgical challenge. In China, most of these patients undergo delayed surgical treatment after clopidogrel withdrawal for at least 5 to 7 days. However, delayed surgery is associated with increased complications and mortality in the older adults. This retrospective paralleled comparison study investigated the safety of early surgery for geriatric hip fracture patients within 5 days of clopidogrel withdrawal. METHODS: Acute hip fracture patients (≥65 years) who were hospitalized in the orthogeriatric co-management ward of Beijing Jishuitan Hospital between November 2016 and April 2018 were retrospectively reviewed. Sixty patients taking clopidogrel before injury and discontinued <5 days before surgery constituted the clopidogrel group. The control group constituted 60 patients not taking antiplatelet or anticoagulant drugs and matched 1:1 with the clopidogrel group for sex, fracture type, operative procedure, and time from injury to operation (±10 h). The primary outcome was perioperative blood loss and the secondary outcomes were transfusion requirement, complications, and mortality. The Student's t test or Wilcoxon signed rank sum test was used for continuous variables and the Chi-square test was used for categorical variables. RESULTS: Age, body mass index, American Society of Anesthesiologists score, and percentage undergoing general anesthesia were comparable between the groups (P > 0.050). The percentages of patients with coronary heart disease (61.7% vs. 18.3%; P < 0.001) and cerebrovascular disease (45.0% vs. 15.0%; P < 0.010) were significantly higher in the clopidogrel vs. control groups, respectively. The median clopidogrel discontinuation time before operation was 73.0 (range: 3.0-120.0) h. There was no significant difference in the estimated perioperative blood loss between the clopidogrel group (median: 745 mL) and control group (median: 772 mL) (P = 0.866). The intra-operative transfusion rate was higher in the clopidogrel group (22/60, 36.7%) than that in the control group (12/60, 20.0%) (P < 0.050). However, there was no significant difference in the blood transfusion rate during the entire perioperative period (26/60, 43.3% vs. 20/60, 33.3%; clopidogrel group vs. control group, respectively; P > 0.050). There was no significant difference in perioperative complications, and 30-day and 1-year mortality rates between the groups. CONCLUSIONS Early hip fracture surgery is safe for elderly patients within 5 days of clopidogrel withdrawal, without increased perioperative blood loss, transfusion requirement, complications, and mortality compared with patients not taking antiplatelet drugs.
Aged ; Case-Control Studies ; Clopidogrel/therapeutic use* ; Hip Fractures/surgery* ; Humans ; Platelet Aggregation Inhibitors/adverse effects* ; Retrospective Studies ; Ticlopidine/adverse effects*

Objective: To compare the efficacy and safety of ticagrelor and clopidogrel in elderly Chinese patients with acute coronary syndrome (ACS) underwent percutaneous coronary intervention (PCI) in the real world. Methods: This study is a post-hoc analysis of a single center, retrospective cohort study. Between March 2016 and March 2018, elderly (age≥65) ACS patients who underwent PCI in the General Hospital of Northern Theater Command were included in the study. The patients were grouped according to P2Y₁₂ receptor inhibitor. The primary endpoints of this study were ischemic events during the 2-year follow-up, which were defined as the composite of cardiac death, myocardial or stroke. The secondary efficiency endpoints included all-cause death and BARC 2, 3, 5 bleeding events. Results: A total of 4 022 elderly (mean age: (71.5±5.3) years) ACS patients were included in this study. Based on the choice of P2Y₁₂ receptor inhibitor, patients were divided into clopidogrel (n=3 201) and ticagrelor (n=821) groups. Incidences of ischemic events (3.2% (26/821) vs. 5.6% (179/3 201), P=0.005) at 2 years were significantly lower in ticagrelor group compared to clopidogrel group. BARC 2, 3, 5 bleeding events (1.7% (14/821) vs. 1.6% (52/3 201), P=0.818) were comparable between the two groups. The incidence of all-cause death (1.5% (12/821) vs. 4.1% (132/3 201), P=0.005) were also lower in the ticagrelor group compared to the clopidogrel group. Clinical outcomes were consistent after adjusting for confounding factors, the incidence of ischemic events (HR= 0.637, 95%CI 0.409-0.991, P=0.046) and all-cause mortality (HR=0.402, 95%CI 0.213-0.758, P=0.005) was significantly lower in the ticagrelor group compared with the clopidogrel group. Risk of BARC 2, 3, 5 bleeding events were similar between the two groups (HR=0.957, 95%CI 0.496-1.848, P=0.897). Conclusion: In real-world clinical practice, for elderly patients with ACS undergoing PCI, ticagrelor use might reduce the incidence of long-term ischemic events and all-cause death without increasing the risk of bleeding.
Acute Coronary Syndrome/surgery* ; Aged ; Clopidogrel/therapeutic use* ; Humans ; Percutaneous Coronary Intervention ; Platelet Aggregation Inhibitors/therapeutic use* ; Retrospective Studies ; Ticagrelor/therapeutic use* ; Treatment Outcome