Antiplatelet Users Research Articles

Impact of Vanessa's Law on the Reporting of Serious Adverse Events: A Retrospective Study Among Antiplatelet Users in a Tertiary-Care Cardiology Centre

BackgroundAntiplatelet drugs, such as clopidogrel, ticagrelor, prasugrel, and acetylsalicylic acid, may be associated with a risk of adverse events (AEs). Vanessa's Law was enacted to strengthen regulations to protect Canadians from drug-related side effects (with mandatory reporting of serious adverse events [SAEs]). ObjectiveTo determine whether Vanessa's Law has led to an increase in SAE reporting among antiplatelet users. MethodsThis descriptive retrospective study was conducted from January, 2018-December, 2021. Included are 260 adult antiplatelet users (cohorts: 2018 [n = 64]; 2019 [n = 79]; 2020 [n = 73]; 2021 [n = 44]) hospitalized at the Institut Universitaire de Cardiologie et de Pneumologie de Québec—Université Laval. The main diagnostic of hospitalization was coded using the International Classification of Diseases,10th revision, Canadian version, and data related to demographic characteristics, hospitalization length-of-stay, drugs administered, and AEs were extracted. ResultsThe 260 antiplatelet users were hospitalized mainly for diseases of the circulatory system (codes [I00-I99]; 2018, 75%; 2019, 71%; 2020, 71%; 2021, 77%) or diseases of the respiratory system (codes [J00-J99]; 2018, 6%; 2019, 8%; 2020, 4%; 2021, 7%). The median age was 70 years. The median duration of hospital stay was 3 days. Among the 1395 AEs recorded during the study, 12% were SAEs. None of the SAEs (or AEs) was reported to Health Canada, either before or after Vanessa’s Law implementation. ConclusionsThese results provide the first picture of reporting trends for SAEs among antiplatelet users in Canada. Investigation of the underreporting of SAEs is needed, as the implementation of a mandatory policy does not seem to have had a favourable impact. Clinical Trial Registration135263.

Impact of Direct Oral Anticoagulant Levels on Functional Independence Following Endovascular Thrombectomy in Patients With Atrial Fibrillation

Background In direct oral anticoagulant (DOAC) users with stroke due to large artery occlusion, endovascular thrombectomy is an effective treatment when intravenous thrombolytic therapy is unsuitable. The purpose of this study is to investigate the association between emergent DOAC levels and endovascular thrombectomy outcomes. Methods Participants with atrial fibrillation, who had a premorbid modified Rankin Scale score of ≤3 and had undergone endovascular thrombectomy for acute stroke, were enrolled. Drug levels upon hospital arrival were measured in the prestroke DOAC users. Head noncontrast computed tomography and computed tomographic angiography images were used to quantify thrombus permeability. The primary outcome was functional independence at 3 months (modified Rankin Scale 0–2 or a return to premorbid status for patients with a premorbid modified Rankin Scale of 3). Results The study included 250 patients (antithrombotic agent nonusers, 42.0%; oral anticoagulant users, 34.0%; and antiplatelet users, 24.0%). The primary outcomes did not differ among the 3 groups. Among oral anticoagulant users, 78.8% were DOAC users. Of the 59 DOAC users with available drug level measurements, 62.7% had low levels (<50 ng/mL). Low‐level patients were less likely to achieve functional independence than high‐level patients (adjusted odds ratio, 0.26 [0.08–0.87]). Compared with antithrombotic nonusers, oral anticoagulant users with therapeutic anticoagulation were more likely to achieve functional independence (adjusted odds ratio, 2.83 [1.18–6.78]), whereas those with inadequate anticoagulation did not. Symptomatic intracerebral hemorrhage occurred in 3 DOAC users in the low‐level group (8.1%), 1 DOAC user in the high‐level group (4.5%), and 4 antithrombotic nonusers (3.8%). Thrombus permeability was similar between antithrombotic nonusers and low‐ or high‐level DOAC users. Conclusion Among patients who underwent DOAC therapy and endovascular thrombectomy, those with low DOAC levels were less likely to achieve functional independence. Furthermore, oral anticoagulant users with therapeutic anticoagulation displayed better functional outcomes than antithrombotic nonusers.

Antithrombotic Treatment and Clinical Outcomes After Intracerebral Hemorrhage: A Retrospective Cohort Study from the Swedish Stroke Register.

A rapid shift has occurred from vitamin K antagonists toward direct oral anticoagulants, which have a lower risk of intracerebral hemorrhage (ICH). However, effects on clinical outcomes after ICH are understudied. We aimed to describe the prevalence of antithrombotic drugs and to study the prognosis among prestroke functionally independent Swedish patients with ICH. We identified all patients diagnosed with nontraumatic ICH in 2017 to 2021 from the Swedish Stroke Register (n=13 155) and assessed death and functional outcome at 3 months after ICH in prestroke functionally independent patients (n=10 014). Functional outcome was estimated among 3-month survivors on the basis of self-reported activities of daily living scores. Risks of outcomes were estimated using Poisson regression. In 13 155 patients, 14.5% used direct oral anticoagulant, 10.1% vitamin K antagonists, and 21.6% antiplatelets at ICH onset. Among 10 014 pre-stroke activities of daily living-independent patients, oral anticoagulants and antiplatelets were associated with increased mortality risk (adjusted risk ratio, 1.27 [95% CI, 1.13-1.43]; P<0.001; and adjusted risk ratio, 1.23 [95% CI, 1.13-1.34]; P<0.001 respectively). Mortality risk did not statistically differ between antiplatelets and oral anticoagulants nor between direct oral anticoagulant and vitamin K antagonists. Among 5126 patients with nonmissing functional outcome (69.1% of survivors), antiplatelets (adjusted risk ratio, 1.06 [95% CI, 0.99-1.13]; P=0.100) and oral anticoagulants (adjusted risk ratio, 1.01 [95% CI, 0.92-1.12]; P=0.768) were not statistically significantly associated with functional dependence. There was no statistically significant difference in mortality risk between direct oral anticoagulant and vitamin K antagonists in prestroke functionally independent patients (unadjusted for oral anticoagulant class indication). Furthermore, mortality risk in antiplatelet and oral anticoagulant users might differ less than previously suggested.

The relationship between changes of antithrombotic drug regimen after ischemic stroke and risks of clinical outcomes in patients with atrial fibrillation

Abstract Background Stroke prevention is central to the management of patients with atrial fibrillation (AF), but the impact of changes in antithrombotic regime following presentation with an ischaemic stroke on subsequent clinical events is unceratin. Methods From 2012 to 2018, 23,165 AF patients who experienced ischemic stroke and survived longer than 90 days after stroke were identified from Taiwan National Health Insurance Research Database. The relationships between post-stroke antithrombotic drug regimen and subsequent clinical outcomes were analyzed. Results Compared to NOACs (reference), there was a significant increase in ischaemic stroke in non-anticoagulated and antiplatelet users (both aHR approx 1.8), with no significant differences to warfarin. The same was evident for a higher mortality in non-anticoagulated and antiplatelet users (aHRs 3.441 and 1.483, respectively). Addition of antiplatelets to NOAC or warfarin resulted in non-significant differences in ischaemic stroke or mortality (Figure 1). Among 769 pateints who received NOACs before and continuously stayed on NOACs after stroke, the shifting to a different NOAC post-stroke was associated with a higher risk of ischaemic stroke (aHR 2.07) as well as the composite outcomes (aHRs between 1.359-1.849), with no difference in major bleeding, mortality or ICH (Figure 2). Conclusions Adding antiplatelet agents to NOACs for AF patients after ischemic stroke did not provide additional clinical benefits. For patients under NOACs who experienced ischemic stroke, the change to a different NOAC post-stroke was not associated with a better clinical outcome.

Effect of antiplatelet and anticoagulant medication use on injury severity and mortality in patients with traumatic brain injury treated in the intensive care unit

BackgroundAntiplatelet and anticoagulant medication are increasingly common and can increase the risks of morbidity and mortality in traumatic brain injury (TBI) patients. Our study aimed to quantify the association of antiplatelet or anticoagulant use in intensive care unit (ICU)–treated TBI patients with 1-year mortality and head CT findings.MethodWe conducted a retrospective, multicenter observational study using the Finnish Intensive Care Consortium database. We included adult TBI patients admitted to four university hospital ICUs during 2003–2013. The patients were followed up until the end of 2016. The national drug reimbursement database provided information on prescribed medication for our study. We used multivariable logistic regression models to assess the association between TBI severity, prescribed antiplatelet and anticoagulant medication, and their association with 1-year mortality.ResultsOf 3031 patients, 128 (4%) had antiplatelet and 342 (11%) anticoagulant medication before their TBI. Clopidogrel (2%) and warfarin (9%) were the most common antiplatelets and anticoagulants. Three patients had direct oral anticoagulant (DOAC) medication. The median age was higher among antiplatelet/anticoagulant users than in non-users (70 years vs. 52 years, p < 0.001), and their head CT findings were more severe (median Helsinki CT score 3 vs. 2, p < 0.05). In multivariable analysis, antiplatelets (OR 1.62, 95% CI 1.02–2.58) and anticoagulants (OR 1.43, 95% CI 1.06–1.94) were independently associated with higher odds of 1-year mortality. In a sensitivity analysis including only patients over 70, antiplatelets (OR 2.28, 95% CI 1.16–4.22) and anticoagulants (1.50, 95% CI 0.97–2.32) were associated with an increased risk of 1-year mortality.ConclusionsBoth antiplatelet and anticoagulant use before TBI were risk factors in our study for 1-year mortality. Antiplatelet and anticoagulation medication users had a higher radiological intracranial injury burden than non-users defined by the Helsinki CT score. Further investigation on the effect of DOACs on mortality should be done in ICU–treated TBI patients.

Persistence and Adherence to Cardiovascular Medicines in Australia.

Background The burden of cardiovascular disease is increasing, with many people treated for multiple cardiovascular conditions. We examined persistence and adherence to medicines for cardiovascular disease treatment or prevention in Australia. Methods and Results Using national dispensing claims for a 10% random sample of people, we identified adults (≥18 years) initiating antihypertensives, statins, oral anticoagulants, or antiplatelets in 2018. We measured persistence to therapy using a 60-day permissible gap,and adherence using the proportion of days covered up to 3 years from initiation, and from first to last dispensing. We reported outcomes by age, sex, and cardiovascular multimedicine use. We identified 83 687 people initiating antihypertensives (n=37 941), statins (n=34 582), oral anticoagulants (n=15 435), or antiplatelets (n=7726). Around one-fifth of people discontinued therapy within 90 days, with 50% discontinuing within the first year. Although many people achieved high adherence (proportion of days covered ≥80%) within the first year, these rates were higher when measured from first to last dispensing (40.5% and 53.2% for statins; 55.6% and 80.5% for antiplatelets, respectively). Persistence was low at 3 years (17.5% antiplatelets to 37.3% anticoagulants). Persistence and adherence increased with age, with minor differences by sex. Over one-third of people had cardiovascular multimedicine use (reaching 92% among antiplatelet users): they had higher persistence and adherence than people using medicines from only 1 cardiovascular group. Conclusions Persistence to cardiovascular medicines decreases substantially following initiation, but adherence remains high while people are using therapy. Cardiovascular multimedicine use is common, and people using multiple cardiovascular medicines have higher rates of persistence and adherence.

Antithrombotic Therapy Increases the Risk of Bleeding after Endoscopic Submucosal Dissection for Early Gastric Cancer: A Propensity Score-Matched Analysis.

Whether antithrombotic agent (ATA) usage increases the risk of gastric post-endoscopic submucosal dissection (ESD) bleeding remains controversial. The aim of this study was to elucidate the effects of usage, type, and cessation timing of ATA on post-ESD bleeding. A total of 4775 early gastric cancer patients undergoing ESD were analyzed; 1:3 propensity score matching between ATA and non-ATA groups resulted in 318 and 767 matched patients in each group, respectively. Outcomes were compared between the two groups using a generalized estimating equation method. After matching, post-ESD bleeding rates in ATA users and non-users were 9.1% and 4.2%, respectively (p = 0.001). In multivariable analysis, ATA usage was independently associated with an increased risk of post-ESD bleeding (adjusted odds ratio: 2.28, 95% confidence interval: 1.34-3.86). Both the continued or insufficient cessation groups and the sufficient cessation group had an increased incidence of post-ESD bleeding compared to their matched controls (12.5% versus 5.2%, p = 0.048; 8.1% versus 3.9%, p = 0.014). Post-ESD bleeding rates in antiplatelet agent users were significantly higher than those of their matched controls (8.3% versus 4.2%, p = 0.010). ATA usage increased the risk of post-ESD bleeding even after its sufficient cessation. Careful observation after ESD is required regardless of the cessation status of ATA.

Can Routine Blood Tests Be Used To Predict The Prognosis of COVID-19 Patients Using Antithrombotic Drugs

Background: COVID-19 may predispose to thromboembolism due to excessive inflammation, hypoxia, and immobilization. We investigated whether these antithrombotic drugs are useful or harmful to tackle COVID-19 and which laboratory parameters are more usable for this purpose. Materials and methods: In our study, patients diagnosed with COVID-19 while using antithrombotic drugs and COVID-19 patients who did not use antithrombotic drugs were compared. Demographic data, laboratory values, clinical results, duration of hospital stay, and mortality were noted and compared. Results: The study was conducted on 236 patients admitted to the emergency department. The mean value of creatine, LDH, PT, NLR, troponin, and ferritin were higher in the drug-using group. Home quarantine and hospitalization rate was 68.8% (n = 33) in antiplatelet users, and 46.2% (n = 6) in the anticoagulant group. Conclusion: The difference between the groups may have been caused by the number of chronic diseases and polypharmacy. The interaction of drugs used for the treatment of COVID-19 with antithrombotic agents is unknown. In addition, as the correlation between COVID-19 and thrombosis is not exactly known, adding antithrombotic drugs to the treatment of the disease is controversial. In our study, the biomarkers used to predict prognosis were worse in COVID-19 patients who continued antithrombotic therapy at the therapeutic dose. In the case of antithrombotic agents, the risks that may arise should always be considered. We recommend monitoring routine blood parameters, especially NLR, LDH, PT, APTT, troponin, and ferritin levels, for the prognosis monitoring of COVID-19 patients who will continue their current antithrombotic therapy

The relationship between abnormal intracranial findings in brain computed tomography and antiplatelet or anticoagulant use in patients with nontraumatic headache: a prospective cohort study.

ObjectiveThis study aimed to investigate the relationship between abnormal intracranial findings on brain computed tomography and antiplatelet or anticoagulant use in patients with nontraumatic headache in the emergency department (ED).MethodsThis was a single-center prospective observational study of patients admitted to the tertiary ED with complaints of nontraumatic headache between May 1, 2016 and September 1, 2016. Anticoagulant or antiplatelet drug use by the patient was recorded. Brain computed tomography (CT) results were categorized into two groups, abnormal results (CT positive) and no pathologic results (CT negative), and compared. The CT positive group included any pathological signs in the brain and the negative group was considered a normal read. A logistic regression analysis was used for evaluating the association of antiplatelets and anticoagulants with abnormal CT findings.ResultsOf the 837 patients with nontraumatic headaches, 157 (18.8%) patients who underwent brain CT scanning were included. The mean age of the patients was 44.4±16.7 years. Eighty-eight (56.1%) of the patients were women. Of the 29 (18.4%) patients using antiplatelets or anticoagulants, 16 (55.2%) were in the CT positive group. There was a statistically significant difference between both groups in terms of drug use compared to the CT negative group (P<0.001). Factors affecting CT results were examined in logistic regression analysis and a statistically significant difference was found in the detection of positive results in antiplatelet or anticoagulant drug users (adjusted odds ratio, 2.478; 95% confidence interval, 1.006–6.102; P=0.048).ConclusionThe use of antiplatelets or anticoagulants in patients admitted to the ED with nontraumatic headache is associated with an increased risk of abnormal intracranial results in brain CT.

Restarting anticoagulant therapy after intracranial hemorrhage in patients with atrial fibrillation: A nationwide retrospective cohort study.

Resuming anticoagulation after an intracranial hemorrhage (ICH) poses a clinical conundrum. The absence of relevant guidelines has led to wide variations in the decision on resuming anticoagulation therapies after ICH. This study aimed to evaluate the risks of an anticoagulation therapy on severe thrombotic events (STE) and severe hemorrhage events (SHE) in Korea and compare the effects of novel direct oral anticoagulants (NOACs) and warfarin in patients with AF. This study was performed using the Korean national health insurance claims data obtained between 2002 and 2017 from individuals who had recently survived an ICH with comorbid AF. The endpoints of this study were STE and SHE. Anticoagulants, antiplatelet agents, and non-antithrombotic users were analyzed for survival with propensity score matching. Among the 4,964 participants analyzed, 878 (17.7%) and 2,070 (41.7%) used anticoagulant and antiplatelet agents, respectively. Anticoagulant (hazard ratio [HR] for STE: 0.385, P<0.0001; HR for SHE: 0.578, P<0.0001) or antiplatelet users (HR for STE: 0.545, P<0.0001; HR for SHE: 0.637, P<0.0001) had a lower risk of STE and SHE than non-antithrombotic users. Anticoagulation 6-8weeks post-ICH showed a tendency of the lowest risk of all-cause mortality (HR: 0.614, P=0.0552). However, there was no difference in the risk between the anticoagulant and antiplatelet users. Further, NOACs were associated with a lower risk of STEs than warfarin (HR, 0.263; P<0.0001). Our results showed that in patients with AF, resuming anticoagulants and antiplatelets after ICH improved the STEs and SHEs. Further, NOAC had additional benefits as compared to warfarin.

Comorbidities and Antithrombotic Treatment Pattern in Patients With Atrial Fibrillation.

ObjectiveNon-vitamin K antagonist oral anticoagulants (NOACs) are proven alternatives to warfarin for preventing stroke in patients with non-valvular atrial fibrillation. We aimed to examine the treatment patterns and patient factors associated with the use of antiplatelet agents, warfarin, and NOACs in clinical practice.MethodsWe conducted a retrospective cohort study using the Korean Health Insurance Review & Assessment Service database. Patients receiving antithrombotics were identified before and after the introduction of NOACs (from August 1, 2013 to December 30, 2014 and July 1, 2015 to November 30, 2016, respectively). Patients were included if they were aged ≥18 years, had an atrial fibrillation diagnosis, and had a CHA2DS2-VASc score ≥2. Treatment pattern was assessed by classifying patients into NOAC, warfarin, or antiplatelet users based on the first date of antithrombotic prescription. Clinical factors associated with the type of antithrombotics chosen were examined using logistic regression analyses.ResultsWe identified 129,465 and 196,243 patients before and after the introduction of NOACs, respectively. The proportion of antiplatelet users was 60.7 and 53.0% before and after the introduction of NOACs, respectively. The proportion of warfarin users was higher in patients with low HAS-BLED score, high CHA2DS2-VASc score, or stroke before the NOAC era. A similar trend was observed for NOAC and warfarin users after the introduction of NOAC. Compared with antiplatelets, warfarin and NOAC uses were significantly associated with CHA2DS2-VASc score and stroke, whereas presence of myocardial infarction (MI) and peripheral arterial disease were significantly associated with antiplatelets prescription. For comparisons between NOAC and warfarin, HAS-BLED and CHA2DS2-VASc scores showed significant associations with NOAC use, whereas comorbidities including MI were significantly associated with warfarin use.ConclusionsThe treatment pattern of antithrombotics did not change with the introduction of NOACs. However, comorbidities served as an important factor in choosing treatment regardless of NOAC entry.

Post-Intracranial Hemorrhage Antithrombotic Therapy in Patients With Atrial Fibrillation.

BackgroundTo investigate the effectiveness and safety of withholding or restarting antithrombotic agents, and different antithrombotic therapies among patients with atrial fibrillation post‐intracranial hemorrhage.Methods and ResultsThis is a nationwide retrospective cohort study involving patients with atrial fibrillation receiving antithrombotic therapies who subsequently developed intracranial hemorrhage between January 1, 2011 and December 31, 2017. The risk of ischemic stroke (IS), recurrent intracerebral hemorrhage (ICH), and all‐cause mortality were investigated between patients receiving no treatment versus patients reinitiating oral anticoagulants (OACs) or antiplatelet agents, and warfarin versus non‐vitamin K antagonist OACs. We applied inverse probability of treatment weighting to balance the baseline characteristics and Cox proportional hazards model to estimate the hazard ratios (HRs) of different outcomes of interest. Compared with no treatment, OACs reduced the risk of IS (HR, 0.61; 0.42–0.89), without increase in the risk of ICH (1.15, 0.66–2.02); antiplatelet agent users showed a similar risk of IS (1.13, 0.81–1.56) and increased risk of ICH (1.81, 1.07–3.04). Use of OACs or antiplatelet agents did not reduce the risk of all‐cause mortality (0.85, 0.72–1.01; and 0.88, 0.75–1.03, respectively). Compared with warfarin, non‐vitamin K antagonist OAC users showed a similar risk of IS (0.92, 0.50–1.70), non‐significantly reduced risk of ICH (0.53, 0.22–1.30), and significantly reduced all‐cause mortality (0.60, 0.43–0.84).ConclusionsOACs are recommended in patients with atrial fibrillation and intracranial hemorrhage because they reduced the risk of IS with no increase in the risk of subsequent ICH. Non‐vitamin K antagonist OACs are recommended over warfarin owing to their survival benefits.

Risk of delayed bleeding after hot snare polypectomy and endoscopic mucosal resection in the colorectum with continuation of anticoagulants.

Current guidelines recommend the temporary discontinuation of anticoagulants before colonoscopic polypectomy, but the effect of this practice on reducing the risk of delayed bleeding after hot snare polypectomy (HSP) and endoscopic mucosal resection (EMR) remains unclear. Our aim was to assess the impact of anticoagulants on the risk of colorectal delayed bleeding after HSP and EMR, and evaluate the necessity of drug withdrawal. We reviewed the clinical data of patients with colorectal polyps using antithrombotic drugs who underwent HSP and/or EMR between January 2016 and September 2020 at Nagaoka Red Cross Hospital. After excluding antiplatelet users, patients were classified into those who continued anticoagulants [continuation group: 50 patients (93 lesions)] and those who discontinued anticoagulants [discontinuation group: 87 patients (190 lesions)]. Delayed bleeding occurred in 12 lesions, and there was no significant difference in the incidence rates between the continuation and the discontinuation groups (3.2% vs. 4.7%; P=0.756). Logistic regression analysis showed that continued use of anticoagulants was not a significant risk factor for delayed bleeding compared to anticoagulant discontinuation (odds ratio, 0.670; 95% CI, 0.177-2.537; P=0.556). There was no significant difference in the incidence rate and risk of delayed bleeding, regardless of the length of the anticoagulant withdrawal period. Continued use of anticoagulants, compared to their discontinuation, did not increase the risk of colorectal delayed bleeding after HSP and EMR. Our results suggest that current guideline recommendations for anticoagulant withdrawal before colonoscopic polypectomy may be reconsidered. UMIN000040449.

Prehemorrhage antiplatelet use in aneurysmal subarachnoid hemorrhage and impact on clinical outcome.

BackgroundLiterature is inconclusive regarding the association between antiplatelet agents use and outcome after aneurysmal subarachnoid hemorrhage.AimsTo investigate the association between clinical outcome and prehemorrhage use in aneurysmal subarachnoid hemorrhage patients as well as the impact of thrombocyte transfusion on rebleed and clinical outcome.MethodsData were collected from prospective databases of two European tertiary reference centers for aneurysmal subarachnoid hemorrhage patients. Patients were divided into “antiplatelet-user” and “non-user” according to the use of acetylsalicylic acid prior to the hemorrhage. Primary outcome was poor clinical outcome at six months (Glasgow Outcome Scale score 1–3). Secondary outcomes were in-hospital mortality and impact of thrombocyte transfusion.ResultsOf the 1033 patients, 161 (15.6%) were antiplatelet users. The antiplatelet users were older with higher incidence of cardiovascular risk factors. Antiplatelet use was associated with poor outcome and in-hospital mortality. After correction for age, sex, World Federation of Neurosurgical Societies score, infarction and heart disorder, pre-hemorrhage acetylsalicylic acid use was only associated with poor clinical outcome at six months (adjusted OR 1.80, 95% CI 1.08–3.02). Thrombocyte transfusion was not associated with a reduction in rebleed or poor clinical outcome.ConclusionIn this multicenter study, the prehemorrhage acetylsalicylic acid use in aneurysmal subarachnoid hemorrhage patients was independently associated with poor clinical outcome at six months. Thrombocyte transfusion was not associated with the rebleed rate or poor clinical outcome at six months.

Antiplatelet therapy and future intracerebral hemorrhage in hemodialysis patients with cerebral microbleeds

The use of antiplatelet drugs is thought to increase the risk for intracerebral hemorrhage (ICH) in patients with cerebral microbleeds (CMBs). However, hemodialysis (HD) patients have a high prevalence of CMBs and diverse pathologies that require antiplatelet therapy. In this study, we investigated whether the use of antiplatelet drugs increases the risk for ICH in HD patients with CMBs. Brain magnetic resonance imaging (MRI), including T2*-weighted MRI, was performed in 179 HD patients with no history of cerebrovascular events. CMBs were detected and patients were followed prospectively with a median follow-up period of 5.2 [1.4–6.2] years. To investigate whether the influence of antiplatelet therapy on the development of ICH differs in cases with and without CMBs, the inverse probability of treatment weighting method was used, including an interaction term between the presence or absence of CMBs and use of antiplatelet drugs. As a result, CMBs were detected in 45 patients (25.1%), and antiplatelet drugs were used in 66 patients (36.9%). When the effect of antiplatelet therapy on the incidence of ICH was modified by the presence of CMBs at baseline (P for interaction <0.001), the use of antiplatelet drugs was a significant risk factor for ICH in HD patients without CMBs, but not in HD patients with CMBs. Furthermore, the burden of CMBs significantly increased the risk for ICH, but the increase in this risk was slower in antiplatelet drug users as compared to non-antiplatelet drug users (P for interaction = 0.02). The influence of antiplatelet drugs on the development of ICH differed depending on the presence or absence of CMBs. In fact, the use of antiplatelet drugs did not increase the risk for ICH in HD patients with CMBs.

Pre-hospital antiplatelet medication use on COVID-19 disease severity

ObjectiveTo evaluate the association between pre-hospitalization antiplatelet medication use and COVID-19 disease severity. DesignRetrospective cohort study. SettingInpatient units at The Mount Sinai Hospital. PatientsAdults age ≥18 admitted between March 1, 2020 and April 9, 2020 with confirmed COVID-19 infection with at least 28 days follow-up. MeasurementsWe captured baseline demographic, pre-hospitalization antiplatelet medication use, and clinical encounter data for all patients who met inclusion criteria. The primary endpoint was peak score on a 6-point modified ordinal scale (MOS), which is based on World Health Organization blueprint R&S groups, used to grade severity of illness through clinical outcomes of interest. Scores indicate the following: 1 – COVID-19 infection not requiring hospitalization, 2 – requiring hospitalization but not supplemental oxygen, 3 – hospitalization requiring supplemental oxygen, 4 – hospitalization requiring high-flow nasal cannula (HFNC) or non-invasive positive pressure ventilation (NIPPV), 5 – hospitalization requiring intubation or extracorporeal membrane oxygenation (ECMO), 6 – death. Multivariable adjusted partial proportional odds model (PPOM) was performed to examine the association between pre-hospitalization antiplatelet medication use and likelihood of each MOS score. Main ResultsOf 762 people admitted with COVID-19, 239 (31.4%) used antiplatelet medications pre-hospitalization while 523 (68.6%) did not. Antiplatelet users were older and had more co-morbidities at baseline. Before adjusting for covariates, patients who used antiplatelet medications pre-hospitalization were more likely than non-users to have peak MOS score 6 (death, OR 1.75, 95% CI 1.21–2.52), peak MOS score ≥5 (intubation/ECMO or death, OR 1.4, 95% CI 1.00–1.98) and peak MOS score ≥4 (HFNC, NIPPV, intubation/ECMO or death, OR 1.40, 95% CI 1.01–1.94). On multivariable adjusted PPOM analysis controlling for 13 covariates, there were no longer any significant differences in peak MOS scores between users and non-users. ConclusionsAfter adjusting for covariates, pre-hospital antiplatelet use was not associated with COVID-19 severity in hospitalized patients.

Safety and efficacy of antiplatelet use before intravenous thrombolysis for acute Ischemic stroke

AimTo study the effects of pretreatment with Antiplatelet (AP) before IV thrombolysis (IVT) on the rate of symptomatic intracranial hemorrhage (sICH) and functional outcome in patients with Acute Ischemic stroke (AIS). MethodIn this retrospective study, the medical records and cerebrovascular images of all the patients who received IVT for AIS in our center in a 9.6-year period were reviewed. Patients who took at least one dose of any APs in the last 24 h prior to IVT were identified. They were categorized according to the type of AP, single versus dual AP therapy (DAPT), and dose of AP. Rate of sICH and functional outcome at discharge were compared between the AP users and non-users. ResultsA total of 834 patients received IVT for AIS in our center during a 9.6- year period. Multivariate models were adjusted for age, NIHSS on admission, history of atrial fibrillation, history of hypertension, INR on admission, history of stroke and diabetes mellitus. In multivariate regression analyses and after adjusting for the variables mentioned above, the use of any AP was not associated with an increased rate of sICH (OR = 1.28 [0.70–2.34], p = 0.425). Furthermore, the use of DAPT did not significantly increase the rate of sICH in multivariate regression analyses. (OR = 0.663 [0.15–2.84], p = 0.580). The patients on any AP had a lower chance of having good functional outcome in univariate analysis (OR = 0.735 [0.552–0.979], p = 0.035). However, when adjusted for age, baseline NIHSS, history of diabetes, hypertension and prior stroke, AP use was not associated with a decreased chance of having a good functional outcome at discharge. (OR = 0.967 [0.690–1.357], p = 0.848). In addition, no significant difference was noted in the rate of good functional outcome between patients on DAPT and no AP users in multivariate regression analyses. (OR = 1.174 [0.612–2.253], p = 0.629). ConclusionOur study did not show any significant association between the risk of sICH and good functional outcome after IVT for AIS patients on AP therapy (dual or single) in comparison with AP naïve patients.

Abstract P609: Restarting Anticoagulant Therapy After Intracranial Hemorrhage With Atrial Fibrillation: A Nationwide Retrospective Cohort Study

Background: Atrial fibrillation (AF) should be treated with anticoagulants to prevent stroke and systemic embolism. Resuming anticoagulation after intracerebral hemorrhage (ICH) poses a clinical conundrum. The absence of evidence-based guidelines to address this issue has led to wide variations in restarting anticoagulation after ICH. This study aimed to evaluate the risks and benefits of anticoagulation therapy on all-cause mortality, severe thromboembolism, and severe hemorrhage and compare the effect of novel direct oral anticoagulants (NOACs) with warfarin on post-ICH mortality in patients with AF. Methods: This retrospective cohort study was performed using health insurance claim data obtained between 2002 and 2017 from individuals with newly developed ICH with comorbid AF. We excluded participants aged &lt; 40 years and those with traumatic ICH, subdural hemorrhage, or subarachnoid hemorrhage. The primary endpoint was all-cause mortality, and the secondary endpoints were severe thrombotic and hemorrhagic events. Anticoagulants, antiplatelet agents, and non-users were analyzed for survival with propensity score matching. Results: Among 6735 participants, 1743 (25.9%) and 1690 (25.1%) used anticoagulants and antiplatelet agents, respectively. Anticoagulant (HR, 0.321; 95% CI, 0.264-0.390; P &lt; 0.0001) or antiplatelet users (HR, 0.393; 95% CI, 0.330-0.468; P &lt; 0.0001) had a lower risk of all-cause mortality than non-users. However, there was no difference between the two drug users (HR, 1.183; 95% CI, 0.94-1.487; P = 0.152; reference: anticoagulant). The risk of acute thrombotic events, although not hemorrhagic events, was significantly lower in anticoagulant users than in antiplatelet users. In addition, anticoagulation between 6 to 8 weeks post-ICH showed a tendency of the lowest risk of death. Further, NOACs were associated with a lower risk of all-cause mortality than warfarin. Conclusions: Our results showed that in patients with AF, resuming anticoagulants between 6 and 8 weeks after ICH improved all-cause mortality, severe thromboembolism, and severe hemorrhage. Further, compared with warfarin, NOAC had additional benefits.

Effect of antiplatelet agent number, types, and pre-endoscopic management on post-polypectomy bleeding: validation of endoscopy guidelines.

It remains unclear whether type of antiplatelet (AP) therapy, AP combination therapy, and AP continuing or switching strategy affect the risk of post-polypectomy bleeding (PPB). In this study, we sought to elucidate this risk. We analyzed 1050 patients who underwent colonoscopic polypectomy: 525 AP users and 525 controls matched for age, sex, comorbidities, concomitant non-steroidal anti-inflammatory drugs use, and polyp characteristics who did not receive antithrombotics. PPB risk was evaluated by AP number, type, and continuing or switching strategies during the peri-endoscopic period. In multivariate analysis, bleeding risk increased significantly as the number of AP agents used increased (monotherapy, adjusted odds ratio [aOR], 3.7; dual antiplatelet therapy (DAPT), 4.6; triple antiplatelet therapy (TAPT), 11.1) compared with controls. With monotherapy, significantly increased PPB risk was found for aspirin (aOR 4.3), thienopyridine (aOR 6.3), and cilostazol (aOR 5.9), but not for eicosapentaenoic acid or other APs (beraprost, limaprost, sarpogrelate, dilazep, or dipyridamole). With DAPT, significantly increased PPB risk was found for combination aspirin plus cilostazol, but not aspirin plus other APs. Bleeding rates for continuing monotherapy were 4.3% for aspirin and 0% for thienopyridine, cilostazol, and other APs, respectively. Analysis of this large polypectomy dataset showed that the use of low-dose aspirin, thienopyridine, or cilostazol and a combination of these is associated with increased PPB risk. Although PPB risk was high with DAPT or TAPT, PPB rate in any antiplatelet monotherapy even with a continuing strategy was low at < 5%.

Risk of rebleeding, vascular events and death after gastrointestinal bleeding in anticoagulant and/or antiplatelet users.

Patients with gastrointestinal bleeding during anticoagulant and/or antiplatelet therapy represent a clinical challenge. To determine the risk/rates of rebleeding, vascular events and death in patients treated with antiplatelet or anticoagulant agents who developed major gastrointestinal bleeding METHODS: This was an observational cohort study of patients who developed gastrointestinal bleeding while on antiplatelet and/or anticoagulant therapy. Drug use information was collected prospectively during bleeding events. Cox proportional hazards models were used to evaluate rebleeding, vascular events and death. Among 871 patients (mean age 78.9±8.6years), 38.9% used an anticoagulant, 52.5% used an antiplatelet and 8.6% used both; 93.1% interrupted treatment after gastrointestinal bleeding and 80.5% restarted therapy within 7.6±36.4days; 38.7% had upper gastrointestinal bleeds, 46.7% lower gastrointestinal bleeds and 14.6% gastrointestinal bleeds of unknown origin. Median follow-up was 24.9months (IQR: 7.0-38.0). Resumption of both therapies was associated with a higher risk of rebleeding, lower risk of ischaemic events or death and a similar risk for upper and lower gastrointestinal events. Resumption of therapy≤7days after bleeding showed a similar pattern with no differences in death. Rebleeding rates were higher in anticoagulant vs antiplatelet patients (138.0 vs 99.0 events per 1000 patient-years), and the bleeding location was identical in 61.8% of cases. Resumption of anticoagulant or antiplatelet therapy after a gastrointestinal bleeding event was associated with a lower risk of vascular events and death and a higher rebleeding risk. The benefits of early reinstitution of anticoagulant/antiplatelet therapy outweigh the gastrointestinal-related risks.