Why clopidogrel instead of aspirin

Another issue in the present study was about the safety profile of aspirin and clopidogrel. Although the risk of intracerebral haemorrhage was similar between the two groups, GI bleeding was more commonly found in patients on clopidogrel than those on aspirin.

It showed contradictory with previous studies [ 6 , 24 ]. Yet, we could not address the reasons behind this finding. This finding, altogether with the higher rates of MACE among clopidogrel group in the present study, might reflect the gaps between the real-world practice and clinical trials.

In the present study, we used real-world data derived from real-world practice that are more in accord with the real-world condition, not under the more stringent selection of the study population in randomized controlled trials RCTs.

Therefore, the efficacy and safety of antiplatelets might yield different results. Real-world data and real-world evidence RWE are increasingly recognized to be of value in health care decisions. Medical product developers also use real-world data and RWE to support clinical trials and observational studies to produce innovative new treatment approaches [ 25 ].

Due to its effectiveness, low cost and availability worldwide, aspirin is still recommended as the first-line antiplatelet agent for secondary stroke prevention [ 3 ]. However, the pharmacoeconomic analysis of aspirin versus clopidogrel thus far in favor of clopidogrel based on the data derived from the CAPRIE trial [ 26 , 27 ].

The cost-effectiveness of both drugs should also be further redefined by using RWE. Based on our findings in addition to the notion that aspirin has much lower cost than clopidogrel, we suggest that the efficacy of aspirin is superior to clopidogrel for ischemic stroke on MACE prevention. Results derived from the present study may be of value to assist clinicians in making decision to choose the more appropriate antiplatelet agent for better longer-term outcome.

There are several limitations in the present study. First, this is a retrospective cohort study with the clinical decision for choosing aspirin or clopidogrel were not well documented. Second, even with PS matching, inherent biases might still exist including confounding factors associated with highly variable health profiles and concurrent use of a variety of medications other than antiplatelet agents.

Those variables might affect the safety and efficacy of antiplatelets agent and proclivity for developing MACE. Third, the findings derived from the present study may not be applicable to other races since this study was mostly on ethnic Chinese patients.

Fourth, there were no adverse events available from the database to enrich the safety profile of both antiplatelets used. Hence, this issue could not be discussed further.

Finally, the present study covers a follow-up period of only 1 year for determining the risk of MACE. Follow-up for longer period is likely to strengthen the apparent difference in long-term risk of developing MACE between 2 patient populations taking aspirin and clopidogrel for secondary stroke prevention.

Compared with clopidogrel, aspirin was associated with a reduced risk of MACE at one-year follow up among ischemic stroke patients. This real-world evidence from Taiwan NHIRD raises the need to re-assess the current therapeutic options related to antiplatelet agents used in secondary stroke prevention.

Browse Subject Areas? Click through the PLOS taxonomy to find articles in your field. Abstract Background Several clinical trials reported that clopidogrel was superior to aspirin in secondary stroke prevention by reducing the risk of major adverse cardiovascular events MACE.

Methods We identified ischemic stroke patients between and who took aspirin or clopidogrel within 7 days of stroke onset for 1-year follow-up. Results From 9, ischemic stroke patients, we found patients on aspirin and patients on clopidogrel who met the selective inclusion criteria. Conclusions Among first-ever ischemic stroke patients, secondary stroke prevention using clopidogrel was associated with higher rates of MACE than aspirin.

Data Availability: All relevant data are within the manuscript. Introduction People with first-ever stroke, especially ischemic stroke have higher risk of recurrence not only within 90 days after the stroke onset but also in life-long follow-up [ 1 , 2 ].

Propensity score matching For reducing the selection bias, we used propensity score PS matching analysis for selected comparisons. Statistical analysis Chi-square test was used to test the different of gender and baseline comorbidities between the aspirin and clopidogrel groups.

Results Before PS matching We collected ischemic stroke patients including patients on aspirin and on clopidogrel. Download: PPT. Table 1. Table 2. Major adverse cardiovascular events, intracerebral haemorrhage, and GI bleeding before and after PS matching.

After PS matching There were ischemic stroke patients on clopidogrel and matched-patients on aspirin. Discussion The present study shows the MACE rate was significantly higher in the clopidogrel group than the aspirin group after one-year follow-up. Conclusions Compared with clopidogrel, aspirin was associated with a reduced risk of MACE at one-year follow up among ischemic stroke patients. References 1. Long-term risk of recurrent stroke after a first-ever stroke.

The Oxfordshire Community Stroke Project. Long-term risk of first recurrent stroke in the Perth Community Stroke Study. Antiplatelet Therapy After Noncardioembolic Stroke. Thienopyridine derivatives versus aspirin for preventing stroke and other serious vascular events in high vascular risk patients. Cochrane Database Syst Rev. The Lancet. View Article Google Scholar 7. Generalizing the results of clinical trials to actual practice: the example of clopidogrel therapy for the prevention of vascular events.

The American journal of medicine. Patients enrolled in large randomized clinical trials of antiplatelet treatment for prevention after transient ischemic attack or ischemic stroke are not representative of patients in clinical practice: the Netherlands Stroke Survey. Criqui MH, Aboyans V. Any reported bleeding events including both composite bleeding events and specific bleeding events were combined e.

These bleeding events were captured from insurance databases or national registries, and it is reasonable to assume that these events were severe enough to require medical attention e. However, due to the nature of the claim-based database and national registries, we were unable to compare bleeding events by severity. In one study [ 22 ], the authors noted that clopidogrel was prescribed only for those with pre-existing gastrointestinal ulcers or bleeding issues or for those who have already failed on aspirin.

This is important to note as the results may not reflect the true rate of bleeding events associated with clopidogrel use. Selecting optimal therapy for secondary stroke prevention requires careful attention, as these patients often present with comorbidities and other risk factors which may influence prescription and treatment effectiveness.

The boxed label warning for clopidogrel cautions against use of clopidogrel in patients with impaired platelet reactivity due to known genetic polymorphisms of CYP2C19 [ 28 ]. The majority of studies in this review included data from before and genotype testing or platelet monitoring via platelet function tests may not have been performed, as routine testing is still not included in any current guideline recommendations.

However, this information was not reported in the studies. Due to the nature of the retrospective cohort studies included in this analysis, clinicians should be aware that unknown and therefore unmeasured confounders might have affected our effect estimates differentially. Aspirin remains the recommended antiplatelet therapy for patients with ischemic stroke in current guidelines [ 8 ]. However, the strength of the evidence in support of clopidogrel over other antiplatelet agents is limited by the few numbers of studies that make direct comparison to clopidogrel as single antiplatelet therapy, and more recent data is based on the combination of clopidogrel and aspirin in mixed populations with ischemic stroke or TIA.

In the absence of further clinical trials, indirect evidence obtained through further meta-analysis and data from prospective patient registries may provide valuable insights on the efficacy and safety of clopidogrel relative to aspirin for secondary prevention patients with ischemic stroke. To our knowledge, this is the first systematic review and meta-analysis conducted in patients with recent ischemic stroke specifically, as most of the current evidence is based on stroke and TIA populations.

We included all published clinical trials and observational studies that made direct comparison of clopidogrel and aspirin monotherapy for secondary prevention in patients with ischemic stroke.

Data from observational studies were included to explore the benefits and harms for this population in the real-world setting. Because there is limited data on the relative efficacy and safety of clopidogrel compared to aspirin alone, these findings can add valuable information to help clinicians and policymakers in selection of antiplatelet therapy for secondary prevention following recent ischemic stroke. This systematic review and meta-analysis found that clopidogrel monotherapy was associated with significantly lower risks of MACCE, recurrent stroke, and bleeding events compared to aspirin in patients with ischemic stroke.

The results of the analysis support clinical benefit for single antiplatelet therapy with clopidogrel over aspirin for secondary prevention in patients with recent ischemic stroke. There were few studies included in this review and data were based largely on retrospective observational data.

More longitudinal data and high-quality studies are warranted to verify the findings of this systematic literature review and meta-analysis. Birsen Ince has received honoraria from Pfizer and Sanofi-Aventis within the past 36 months, outside the submitted work. Kursad Kutluk has received honoraria from Boehringer Ingelheim, Pfizer and Sanofi-Aventis within the past 36 months, outside the submitted work. Dara Paek, Jung Min Han, and Michael del Aguila report employment by Doctor Evidence at the time in which this research was conducted, who was contracted by Sanofi to perform the analysis.

Shalini Girotra reports employment by Sanofi. All other authors have nothing to disclose. All authors met ICMJE guidelines for authorship and provided analysis interpretation, critical review, revision, and final approval of the article.

Paciaroni, D. Paek, M. Paek, J. Han, and M. The authors thank Toby Sayre of Doctor Evidence for medical writing and support and Angelica Stamegna for general publication management.

The supplementary PDF includes summaries of the search strings, in addition to further information on methodology and results. Supplementary Materials. This is an open access article distributed under the Creative Commons Attribution License , which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Article of the Year Award: Outstanding research contributions of , as selected by our Chief Editors.

Read the winning articles. Journal overview. Special Issues. Academic Editor: Joel C. Received 16 May Revised 16 Aug Accepted 17 Sep Published 01 Dec Abstract Aim. Introduction Stroke is the second most common cause of death and the third most common cause of disability worldwide [ 1 ]. Methods 2. Study Selection Medical librarians screened titles and abstracts based on a standardized review protocol that defined study eligibility criteria using the PICOTSS format, which outlines the participants, interventions, comparators, outcomes, timing, setting, and study designs of interest Table 1.

Table 1. Figure 1. Figure 2. Forest plots showing pooled risk ratio of a MACCE, b any ischemic or hemorrhagic stroke, c recurrent ischemic stroke, and d all-cause mortality. Figure 3. Table 2. References V. Feigin, G. Roth, M. Naghavi et al. Benjamin, M. Blaha, S.

Chiuve et al. Feng, R. Hendry, and R. Engel-Nitz, S. Sander, C. Harley, G. Rey, and H. Burn, M. The result was driven primarily by reductions in ACS rehospitalizations, stroke, and major bleeding. These benefits were consistent across all prespecified subgroups, with no significant group differences in mortality. These findings suggest that clopidogrel monotherapy is both more effective and safer than low-dose aspirin in patients who have completed 6 to 18 months of DAPT after coronary stenting.

Although the study was conducted exclusively in East Asian patients, the consistency of its results with those of the CAPRIE trial suggests that extrapolation to North American and European populations is reasonable.

Given that clopidogrel is generic and relatively inexpensive, it may be time to consider it as the default drug for secondary prevention in many patients with atherosclerotic vascular disease. Koo B-K et al. Aspirin versus clopidogrel for chronic maintenance monotherapy after percutaneous coronary intervention HOST-EXAM : An investigator-initiated, prospective, randomised, open-label, multicentre trial.

Lancet May 16; [e-pub]. Lancet May 16 A large Korean study suggests that clopidogrel alone is preferred after the initial period of dual antiplatelet therapy.