Anticoagulant Users Research Articles

Atrial fibrillation outcomes in patients from Asia and non-Asia countries: insights from GARFIELD-AF

BackgroundDifferences in the clinical outcomes and level of risk among Asian versus non-Asian patients with atrial fibrillation (AF) have been sparsely investigated.ObjectiveTo provide a contemporary prospective comparison of outcomes for newly diagnosed patients with AF, between Asian and non-Asian regions.MethodsSix Asian countries (China, Japan, India, Singapore, South Korea and Thailand) and 29 countries outside Asia participated in the Global Anticoagulant Registry in the FIELD-AF (GARFIELD-AF) study. Newly diagnosed patients with AF, enrolled between 2010 and 2016, were followed up for≥2 years. The outcome studies were all-cause, cardiovascular and non-cardiovascular mortality, non-haemorrhagic stroke/systemic embolism (SE), major bleeding. The association of geographical region with clinical outcomes (event rates per 100 person-years) were estimated using multivariable Cox models.Results13 841/52 057 (26.6%) GARFIELD-AF participants were enrolled in Asia. Average age and prevalence of cardiovascular comorbidities were lower than in non-Asian countries and patients at high risk of stroke (ie, CHA2DS2-VASc≥2 excl. sex) were less frequently anticoagulated (60.1% vs 73.2%). Non-vitamin K oral anticoagulant (NOAC) was similar in both regions (∼28%), though Asian patients were more frequently underdosed. Both Asian and non-Asian patients who received NOAC at enrolment experienced lower all-cause mortality and non-haemorrhagic stroke/SE compared with patients on other treatments or none.All-cause mortality, non-cardiovascular mortality and major bleeding were less frequent in patients from Asia versus non-Asia (HR (95% CI): 0.62 (0.39 to 0.99), 0.52 (0.28 to 0.97), 0.58 (0.36 to 0.96), respectively). Associations of moderate-to-severe chronic kidney disease and vascular disease with increased risk of all-cause mortality were stronger in Asian versus non-Asian patients (interaction p values: 0.0250 and 0.0076, respectively). There was notable heterogeneity in oral anticoagulant (OAC) usage within the Asian countries.ConclusionsPatients in Asian countries had a lower risk of all-cause mortality and major bleeding compared to the rest of the world. NOAC had evident benefits for reducing mortality and stroke across populations. Further studies on sociocultural impacts on OAC outcomes are needed.Trial registration numberClinicalTrials.govNCT01090362.

Effect of antiplatelet and anticoagulant medications on implant survival: a long-term retrospective cohort study

PurposeThis large-scale retrospective study aimed to examine the long-term effect of antiplatelet and anticoagulant medications intake on dental implant treatment outcome.Materials and methodsThis study retrospectively examined data from patients who underwent dental implant procedures at several university dental clinics within the BigMouth network between 2011 and 2022. Patients’ characteristics including age, gender, ethnicity, race, tobacco use, systemic medical conditions and intake of antiplatelets and anticoagulants were analyzed. Implant treatment outcome was the main outcome variable. Implant failure was defined as the removal of a dental implant for any reason. Time to failure (date of procedure to date of visit with failure) was recorded, while sites without a failure were censored at the last follow-up visit.ResultsA total of 50,333 dental implants in 20,842 patients over 12 years were analyzed and an implant failure rate of 1.4% at the implant level and 2.7% at the patient level were found. Asians, African-Americans, American Indians or Alaskan Natives, and White individuals were significantly more likely to receive antiplatelet medications than Hispanics or Latinos. Males and smokers exhibited significantly higher odds of being antiplatelet and anticoagulant users compared to females and non-smokers, respectively. When the implant survival rates between antiplatelet and anticoagulant users were compared to non-users, no significant differences were observed.ConclusionWithin the limitations of this study, it appears that the use of anticoagulant and antiplatelet medications does not affect the risk of implant failure. Both anticoagulant and antiplatelet users and non-users exhibit similar high implant survival rates.

Evidence that anticoagulant use decreases in-hospital deaths in patients with new-onset atrial fibrillation.

Current guidelines provide no clear recommendations for managing new-onset atrial fibrillation in critical illness, particularly with respect to anticoagulant use. This retrospective study aimed to evaluate the efficacy and safety of anticoagulants in such patients. Patients in the intensive care unit with new-onset atrial fibrillation were recruited during the period January 1, 2021, to June 30, 2022. Ischemic stroke and bleeding were considered primary outcomes, and in-hospital death was considered the secondary outcome. Hazard ratios for outcomes were determined using the Cox proportional hazard model. A total of 92 patients were included in the study of which 29 were anticoagulant users and 63 non-users. No significant differences were observed on the risk of ischemic stroke (HR, 3.46; 95% CI, 0.22-55.8, p=0.38) and bleeding (HR, 1.07; 95% CI, 0.52-2.23, p=0.85), but anticoagulant use was associated with a significantly decreased risk of in-hospital death (HR, 0.43; 95% CI, 0.19-0.97, p=0.04). Anticoagulant use in critically ill patients with new-onset atrial fibrillation did not increase the risk of bleeding and ischemic stroke but significantly reduced in-hospital deaths. These findings need confirmation in a randomized controlled trial.

Differences in coronary microcirculation measurements during regadenoson vs. adenosine - induced hyperemia.

Little is known about the similarity of microcirculation assessment outcomes performed with regadenoson and adenosine. The aim of the current study was to compare coronary flow reserve (CFR) and index of microcirculatory resistance (IMR) assessment using adenosine and regadenoson, and to evaluate predictors regarding the size of differences. 44 patients were enrolled and diagnosed between 2021 and 2023. Fractional flow reserve (FFR), CFR and IMR were measured twice in the circumflex (Cx) (n = 8) or left anterior descending (LAD) (n = 36) artery: once with continuous infusion of adenosine (Adenocor 140 µg/kg/min) and 10 minutes later with regadenoson (Rapiscan 400 µg i.v.). Averaged results were quantified with adenosine and regadenoson for FFR (0.81 [0.75 ÷ 0.89] vs. 0.80 [0.73 ÷ 0.88]), CFR (3.84 [1.67 ÷ 4.08] vs. 3.97 [1.78 ÷ 4.32]) and IMR (20.01 [11 ÷ 24.5] vs. 20.25 [10.75 ÷ 23]), respectively. None of the differences were statistically significant. Among the significant (p < 0.05) predictors of greater ΔCFR, the following can be noted: prior percutaneous transluminal angioplasty/carotid artery stenting (β = 2.35), oral anticoagulant usage (β = 0.89), and prior stroke/transient ischaemic attack (TIA) (β = 1.09), with the latter being also confirmed for greater ΔIMR (β = 8.89). Moreover, patients with New York Heart Association (NYHA) class II/III, as compared to those with NYHA class I, were more likely to have greater ΔIMR (β = 11.89). Regadenoson may be a feasible alternative to adenosine in coronary microcirculation assessment, as it produces similar outcomes. Selected factors were found to be predictors of greater differences in IMR, CFR and FFR values according to the agent used for coronary hyperemia.

Anticoagulation Usage and Thrombolytic Therapy in Subjects with Atrial Fibrillation Associated Ischaemic Stroke.

Background. Atrial Fibrillation (AF) causes up to 20% of ischaemic strokes and 30% in some populations such as those over 80 years. Previous research in our population showed that widespread adoption of Direct Oral Anticoagulant (DOAC) prophylaxis had not been associated with a reduction in AF associated stroke prevalence but there was a considerable rate of breakthrough stroke in patients receiving anticoagulation and anticoagulation rate may be affected by increasing use of DOACs. Aims: We undertook a more detailed study using the Irish National Audit of Stroke (INAS) to determine the characteristics of anticoagulation practice in AF associated stroke, particularly breakthrough stroke, adherence to prescribing guidelines and effect on thrombolysis rate. Methods: Data from INASwere analysed for the period 2017-2022 inclusive as part of a cross-sectional, cohort study. Data on pre stroke, and discharge disability (modified Rankin Score (mRS)) were collected in addition to age, sex, length of stay and thrombolysis rate. An enhanced dataset with additional questions about adherence with prescription, reasons for non-concordance and International Normalized Ratio (INR) control for receiving Warfarin was collected for 2022 was also considered separately. Comparisons for continuous / quantitative data were made using Student’s t tests and for proportional data using Pearson’s Chi Square statistics and logistic regression analyses Results. Complete AF Data were available on 22485 of 26829 strokes admitted over this period. Of these strokes with AF data, 19260 (85.6%) were ischaemic, mean age was 71.8 and 57.1% male. AF was found in 5321 of these ischaemic strokes and this AF was identified pre-stroke in 2835 in 2835 (53.3%). 80.4% of patients with known AF had been prescribed anticoagulation. The population with previously unknown AF were significantly younger on average than those on anticoagulation (76.8 years vs. 79.1 years (p&lt;0.0001, t-test)), or those with AF and not anticoagulated; 78.8 years (p&lt;0.0001), they were also much more likely to have received thrombolysis (17.3 % vs. 4.0% (Chi Sq, p&lt;0.0001)). Of patients receiving DOACs, only 52 received thrombolysis (2.9%) compared with 37 (8.5%) of the VKA Group (Chi Sq 29.0 p&lt;0.0001). Or regression analysis, anticoagulation was not associated with differences in excellent outcome (mRS 0 or 1) achieved (OR 1.064, p=0.41) or with mortality. (OR 1.014, p=0.89). There were 4999 strokes in 2022, 4272 (85.4%) were ischaemic and 1270 (29.7%) of ischaemic strokes were AF associated. Of the 557 AF associated ischaemic strokes anticoagulated at presentation, 84.6% were prescribed DOACs. Forty-eight (9.5%) had their anticoagulation paused and 40 admitted to poor compliance (7.9%). Conclusion. Nearly half of people with AF identified had not previously had the arrhythmia detected pre-stroke. Those admitted with known AF were mainly appropriately treated with DOACs and constitute breakthrough strokes. Subjects receiving DOACs were much less likely to receive thrombolytic therapy even than those taking Warfarin. Data access: INAS data is publicly accessible. Data is available on application to National Office of Clinical Audit, Ireland.

Use of common cardiovascular disease drugs and risk of dementia: A case-control study in Swedish national register data.

Cardiovascular drug use may help prevent dementia; however, current evidence is mixed. Using a case-control design, we investigated the association between duration and combination of multiple cardiovascular drug classes and incident dementia. From the Swedish national registers, we included 88,065 incident dementia cases aged ≥70 at diagnosis between 2011 and 2016 and 880,650 age- and sex-matched controls. Cardiovascular drug use was ascertained from the Prescribed Drug Register. Long-term users (≥ 5years) of antihypertensives, diuretics, lipid-lowering drugs (LLDs), and oral anticoagulants (OACs) had statistically significantly fewer dementia diagnoses (odds ratio [OR] 0.75-0.91) than non-users. Antiplatelets use was associated with more dementia diagnoses (OR 1.13-1.25). Use of antihypertensives in combination with diuretics, LLDs, and OACs for ≥5 years was associated with fewer dementia diagnoses (OR 0.66-0.84). Preventing dementia via cardiovascular drug pathways may be possible. It is however important to consider the potential long-term negative cognitive effect of antiplatelets. Use ≥5 years of common cardiovascular drugs was associated with lower dementia risk. Common cardiovascular drug combination use was associated with lower dementia risk. Anti-platelet use of any duration was associated with higher dementia risk.

Meta-Analysis Investigating Optimal Timing of Chemoprophylaxis for Venous Thromboembolism in Operatively Managed Blunt Spinal Injuries.

Blunt spinal injuries (BSIs) are associated with substantial morbidity and mortality. Management typically involves stabilization of the spinal column and may include chemoprophylaxis for venous thromboembolism (VTE) prevention. The optimal timing of chemoprophylaxis initiation in operatively managed BSI patients remains debated. Analyze available literature on optimal chemoprophylaxis timing for the prevention of VTE in patients postinjury undergoing operative repair. Systematic review and meta-analysis. A systematic review and meta-analysis were conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. PubMed and MEDLINE were searched for studies assessing chemoprophylaxis timing in adult BSI patients. Inclusion criteria focused on operatively managed BSIs and anticoagulant usage assessment. Three studies involving 4345 patients were included. Early chemoprophylaxis initiation was associated with significantly lower deep vein thrombosis (DVT) and overall VTE incidence compared with late initiation. No significant differences were found in pulmonary embolism (PE) incidence or mortality. Early anticoagulant administration after spinal fixation for BSI reduces DVT and overall VTE risk without impacting PE incidence or mortality. Further research is recommended to solidify these findings and address existing gaps in the literature. Early chemoprophylaxis initiation in operatively managed BSI patients reduces DVT and overall VTE risk without affecting PE incidence or mortality LEVEL OF EVIDENCE: 2.

Timing of Anticoagulation Resumption After Spontaneous Rectus Hematoma

Objective:Rectus sheath hematoma (RSH) is a rare condition characterized by acute abdominal pain and development of a mass on the abdominal wall. It is caused by bleeding resulting from the rupture of one of the inferior epigastric arteries or a tear in the rectus muscle. It is associated with trauma and anticoagulant usage. Although there have been no substantial advancements in the diagnosis and treatment of RSH in recent years, it is anticipated that the incidences of RSH will increase with the rising use of anticoagulants. Surgery is rarely performed, but patients are monitored in general surgery departments. Treatment requires maintaining a delicate balance between the risks of bleeding and thrombosis. This study aims to present nontraumatic RSH cases treated in our clinic, supported by a review of the literature. Methods: This retrospective multicenter study included patients over 18 years of age who were admitted with a diagnosis of nontraumatic RSH between 2020 and 2021 at the Department of General Surgery, Kahramanmaras Sutcu Imam University Faculty of Medicine, and the General Surgery Clinic of Kayseri City Hospital. Patients diagnosed with RSH were identified by reviewing clinical protocol records and digital databases. The demographic data of the patients, such as age and gender, physical examination findings at admission, medications used, comorbidities, complete blood count, international normalized ratio and other laboratory information, imaging methods used for diagnosis, and receipt and quantity of blood products, were recorded. Following diagnosis, patients were monitored for one month for bleeding (recurrent bleeding, gastrointestinal bleeding, and intracranial bleeding) and thrombotic complications (heart valve thrombosis, cerebrovascular events, and pulmonary embolism). Results: Of the 32 patients included in the study, 24 were men (75%) and eight were women (25%). Abdominal pain and palpable swelling were common complaints in all patients. Patient age ranged between 27 and 92 years with a mean age of 70.6 ± 12.9 years. Mean length of hospital stay was 12.6 ± 12.0 days, and 28% of the patients stayed in the intensive care unit for a mean duration of 2.8 ± 6.3 days. Correlation analysis revealed a weak positive correlation between the size of the hematoma on imaging and length of hospital stay and a weak negative correlation between Hb value at diagnosis and length of hospital stay (p = 0.017 and r = 0.426). Conclusion: Nontraumatic RSH is a potentially fatal condition that requires hospitalization and intensive care unit admission as well as substantial amounts of blood transfusion. There is a relationship between the imaging method used at admission and the length of hospital stay as well as the hemoglobin level of the patient.

Streamlining Atrial Fibrillation Care: Building a Comprehensive Program to Provide High-Quality, Individualized Care.

Atrial fibrillation is the most common sustained arrhythmia with a variable presentation ranging from asymptomatic incidental diagnosis by physical examination or electrocardiogram screening, to severely symptomatic requiring emergent treatment. The variation in care represents an opportunity to build a comprehensive center of excellence within a hospital system. We present our experience building the Swedish Comprehensive AFib Network and a dedicated AFib clinic at a large quaternary urban medical center. We focused on patient and referral engagement, standardized protocols to promote best practices, data collection to improve quality of care, and broad evaluation of a single but multidisciplinary disease process. We hope this can offer insight into how other programs can be started for atrial fibrillation or other disease-focused clinics. We report our experience in the first 2years, having evaluated over 700 new patients, and demonstrated an improvement in the rate of anticoagulation usage and a reduction in hospitalizations among patients included in our program.

Risk of thromboembolic and haemorrhagic events associated with anticoagulation among 11,355 patients with non-valvular atrial fibrillation and thrombocytopenia

Abstract Background Oral anticoagulation (OAC) is the mainstay for stroke prophylaxis in patients with non-valvular atrial fibrillation (NVAF). Management is challenging among patients with NVAF complicated with thrombocytopenia. Purpose We compared risk of thromboembolic and hemorrhagic events between vitamin-k antagonist (VKA) and direct oral anticoagulants (DOAC) users. Methods We retrospectively analyzed patients with thrombocytopenia and NVAF prescribed VKA (N=5,251, 46.2%) and DOAC (N=6,104, 53.8%) between January 2012 and July 2022 in 16 public hospitals in Hong Kong. Mild to moderate thrombocytopenia was defined as mean platelet count (PLT) 100-150 × 10^9/L and 50-100 × 10^9/L respectively, during the year of OAC initiation. Propensity-matched cohorts of VKA and DOAC were generated on the basis of age, sex, baseline co-morbidities (components of CHA2DS2VASC and HAS-BLED scores) and medications. Time to intracranial hemorrhage (ICH), gastrointestinal bleeding (GIB) and ischemic stroke (IS) was analyzed using competing risk regression, accounting for death as competing risk. Subgroup analysis was performed to detect heterogeneity of effect across mild and moderate thrombocytopenia. Secondary outcome included (i) comparisons between 4 DOAC agents with full dose; (ii) Full-dose DOAC vs. reduced-dose DOAC. Results Of the whole cohort (N=11,355, mean age 75.8±10.5, female 38.6%), 10.3% (n=1,174) and 89.7% (n=10,181) had moderate and mild thrombocytopenia, respectively. After propensity-score matching, VKA and DOAC (n=4,302 each cohort) users were well balanced at baseline characteristics, with a median follow-up of 4.0 (IQR: 1.6-7.3) years. Overall, utilization of DOAC was associated with reduced risk of ICH [Hazards Ratio (HR) 0.56 (95% CI 0.45-0.70)] and GIB [HR 0.60 (95% CI 0.48-0.75)], compared with VKA. No difference in risk of IS was observed [HR 1.00 (95%CI 0.83-1.20)]. Dosing reduction of DOAC made no difference in all outcomes. Subgroup analysis demonstrated the benefit in decreasing GIB might be more marked in moderate thrombocytopenia [(HR 0.24 (95%CI 0.09-0.61)], than in mild thrombocytopenia [HR 0.64 (95%CI 0.51-0.81)]. Conclusion In patients with NVAF and thrombocytopenia, DOAC has similar efficacy but better safety profile than VKA. In terms of GIB, the superiority appeared to be more pronounced in patients with more significant thrombocytopenia.

Life-Threatening Spontaneous Hematoma in Unusual Sites in Patients with COVID-19 on Anticoagulant Therapy: A Case Series

Thromboembolic manifestations are a common phenomenon in patients affected by corona virus (SARS CoV-2). Recent studies have shown that patients with acute renal failure are also at a greater risk of venous and arterial thromboembolism, 15-30% in ICU, and 7% inpatient care. However, frequently unjudicial use of anticoagulants may develop severe life-threatening hematoma. In our hospital settings we had a dedicated COVID Unit with a Hemodialysis facility. Our Nephrology department had managed 381 patients being COVID positive along with renal impairment from March 2020 to January 2022. Among these patients, four patients developed spontaneous non traumatic hematoma in unusual sites. On admission all the patients received treatment according to our national guidelines for COVID-19. Cases: It is a retrospective analysis in a single-centered hospital. Four cases with confirmed COVID-19 with acute kidney injury and on anticoagulant therapy had developed sudden concealed bleeding. These patients had no previous history of anticoagulant therapy before admission. Case 1 developed hemorrhage in Right lower anterior paramedian deep parietal wall of abdomen, Case 2 had hematoma in retroperitoneal space and in lower third of Iliopsoas, Case 3 developed hemorrhage in left cerebral hemisphere, Case 4 had Intramuscular Hematoma in left rectus abdominis. Out of these four patients two of them required Hemodialysis and one of them went into shock. All patients included were male. The mean age was 57±19.64years. All the four patients were initially managed conservatively with keen monitoring and with proper volume resuscitation, blood transfusion and discontinuation of the anticoagulants. Three of the patients survived with conservative management and one patient died due to sudden massive cardiac arrest. The use of therapeutic anticoagulant can increase the risk of bleeding in atypical sites and may exhibit higher patient death with COVID-19 if not identified at early stage. So a risk-benefit ratio of usage of anticoagulants should be kept in mind and further clinical trials needed to justify its random use in COVID-19. J Bangladesh Coll Phys Surg 2024; 42: 393-400

Association between warfarin and direct oral anticoagulants users and risk of mortality: cohort studies in England and Hong Kong

Abstract Background The evidence of the association between warfarin and risk of mortality compared with direct oral anticoagulants (DOACs) has been mixed in current literature. Purpose To investigate the association between all-cause mortality and warfarin, compared with DOACs. Methods Population-based cohort studies were conducted using the data from the Hong Kong Clinical Data Analysis and Reporting System (CDARS) and United Kingdom Clinical Practice Research Datalink (CPRD) Aurum. People with atrial fibrillation aged ≥18 years who initiated warfarin or a DOAC during the study period (1st Jan 2014 - 31st Dec 2019) were identified. Follow-up started from the first date of oral anticoagulant prescription and ended at earliest of the date of death, the day before drug switching (between warfarin and DOACs), transferring out of the practice (CPRD Aurum only), last data collection date for the practice (CPRD Aurum only) or the end of study period. We estimated propensity score (PS) based on the list of potential confounders including demographics, co-morbidities, co-medications and polypharmacy. Cox proportional hazards regression model with PS-weighting was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). Results Among 227,190 new oral anticoagulant users, 54,367 (23.93%) died. The median follow-up was 2.96 and 2.45 years in CPRD and CDARS, respectively. Compared with DOAC use, a lower hazard of all-cause mortality was found in warfarin use (PS-weighted hazard ratio [HR]=0.94, 95% confidence interval [CI]=0.89-0.99) in CPRD; while a higher hazard was observed in warfarin users (PS-weighted HR=1.31, 95% CI=1.24-1.39) in CDARS, versus DOAC users. Consistent results were seen in both databases when stratified warfarin users by Time in Therapeutic Range (TTR). We observed a lower hazard of all-cause mortality in warfarin users with TTR≥65% (PS-weighted HR=0.90, 95% CI=0.85-0.94 in CPRD; 0.87, 0.79-0.96 in CDARS) and increased hazard in warfarin users with TTR&amp;lt;65% (PS-weighted HR=1.37, 95% CI=1.25-1.49 in CPRD; 1.57, 1.48-1.66 in CDARS), versus DOAC users. Conclusions The hazard of all-cause mortality associated with warfarin compared with DOACs were found to be conflicting across databases. However, both databases consistently showed that an increased hazard of all-cause mortality was only found in warfarin users with TTR&amp;lt;65% but not in those with TTR≥65%, suggesting that the differences in hazard of all-cause mortality associated with warfarin compared with DOAC, in part may depend on anticoagulation control in warfarin users. We recommend that warfarin users with poor INR control warrant closer clinical attention and could be considered for a switch to DOACs.

Antibiotic prescribing patterns and risk of antibiotic-resistant infections and Clostridium difficile in Warfarin and Direct Oral Anticoagulant users: matched population-based cohort study

BackgroundWarfarin and Direct Oral Anticoagulant (DOAC) users may have more frequent antibiotic prescriptions than non-users. The aim of this study was to estimate rates of common and resistant infections, and antibiotic prescribing amongst warfarin and DOAC users versus non-users.MethodsThis matched retrospective cohort study used data from patients registered with General practices in England contributing to the Clinical Practice Research Datalink GOLD. We included 61,750 adults who initiated warfarin or a DOAC between 1st January 2011 and 31st December 2019, matched 1:1 to non-users. We estimated Incident Rate Ratios (IRR) and 95% Confidence Intervals for three common infections and all-cause antibiotic prescribing. We estimated hazard ratios (HRs) and 95% CIs for the risk of methicillin resistance Staphylococcus aureus (MRSA), other antibiotic-resistant organisms, or Clostridium difficile. We assessed the extent to which any of the effect of warfarin and DOAC use on antibiotic resistant infections or Clostridium difficile was mediated by antibiotic prescribing patterns.Results37,143 warfarin users and 24,607 DOAC users were matched 1:1 to non-users. Warfarin and DOAC users had greater relative consultation rates for respiratory, urinary, and skin infections. All-cause antibiotic prescribing was greater in warfarin and DOAC users (warfarin; adjusted IRR 1.47, 95% CI 1.45–1.50, DOAC; adjusted IRR 1.66, 95% CI 1.63–1.69). Largest effect sizes were observed for flucloxacillin (adjusted IRR 2.11, 95% CI 2.01–2.20), and erythromycin (adjusted IRR 2.32, 95% CI 2.00–2.70). Warfarin users had significantly higher risk of MRSA (adjusted HR 1.68, 95% CI 1.38–2.05) and hospital admission with antibiotic resistant infections (adjusted HR 1.91, 95% CI 1.11–3.30). DOAC users had significantly higher risk of MRSA (adjusted HR 1.57, 95% CI 1.20–2.06), hospital admission with antibiotic resistant infections (adjusted HR 2.13, 95% CI 1.61–2.82), and Clostridium difficile (adjusted HR 1.45, 95% CI 1.10–1.92). We found little evidence to suggest that the increased risks of studied outcomes were mediated by rates of antibiotic prescription.ConclusionWarfarin and DOAC use was associated with greater rates of infection consultations, all-cause antibiotic prescribing, antibiotic resistant infections, and Clostridium difficile, but there was little evidence that antibiotic prescribing rates mediated risk of resistant infections or Clostridium difficile.

Exploring bleeding in oral anticoagulant users: assessing incidence by indications and risk factors in the entire nationwide cohort.

Oral anticoagulants (OACs) are essential for the prevention and treatment of thromboembolic disorders, but bleeding, a major complication, can have a fatal impact on the patient's treatment. We aimed to estimate the nationwide, real-world incidence rate of bleeding in patients taking OACs and confirm the incidence by indications and risk factors. This cross-sectional study identified OAC users from April 1 to December 31, in both 2019 and 2020, using the HIRA-NPS database. The primary outcome variables were the incidence rate of major bleeding events during OAC treatment and within 30 days of treatment discontinuation. We estimated the adjusted incidence rate ratio (aIRR) in subpopulations. Among 18,822 OAC users, the incidence rate of major bleeding was 27.9 (95% CI: 24.6-31.5) per 1,000 person-years. The incidence rate of major bleeding was higher in patients with a bleeding history, with an aIRR of 11.51; those at high bleeding risk (HAS-BLED score ≥3), with an aIRR of 1.51; those with high CCI scores ≥3, with an aIRR of 1.88; and those with liver disease, with an aIRR of 1.41. For indications, compared to patients with nonvalvular atrial fibrillation (NVAF), the aIRR of major bleeding was significantly higher at an aIRR of 2.35 in patients undergoing VTE treatment. Patients with ischemic stroke showed a higher incidence of major bleeding with an aIRR of 2.13 than NVAF patients. The aIRR of major bleeding in the oral anticoagulant group, compared to the matched control group, was 2.25 (95% CI: 1.93-2.63). These findings may be useful for implementing strategies to improve the evaluation and management of anticoagulation-related bleeding.

O02 SIMULTANEOUS BLOOD PRESSURE AND ATRIAL FIBRILLATION SCREENING IN MAY MEASUREMENT MONTH 2022

Background and objective: May Measurement Month (MMM) is a global campaign aiming to raise awareness of raised blood pressure (BP). In 2022, concurrent screening for BP and atrial fibrillation (AF) was conducted in ten countries, given that hypertension and AF are both major treatable risk factors for stroke. Here, we evaluate AF prevalence and treatment by BP status among opportunistic samples of adults. Methods: In MMM, adults (≥18 years) undergo opportunistic BP screening. In ten participating countries, concurrent AF screening was carried out using OMRON Complete or M7 devices, in addition to three standardized, sitting BP measurements. ‘Known’ AF was defined as having had a previous diagnosis of either AF or irregular heartbeat, or taking oral anticoagulants. To risk-stratify those with AF, we calculated the CHA2DS2-VASc score. Hypertension was defined as a BP ≥140 and/or ≥90 mmHg (average of the second and third readings) and/or taking BP-lowering medication. Results: 80,751 adults (mean age 50.1 years; 58.2% female) underwent BP and AF screening. AF was detected in 1,526 (1.9%), of whom 1,014 (66.4%) had ‘known’ AF. Of those with ‘known’ AF, 214 (21.1%) were taking anticoagulants and 644 (63.5%) were taking neither anticoagulants nor aspirin. AF was detected more commonly among those aged ≥60 than &lt;60 (3.2% vs 1.2%: p&lt;0.001). Hypertension was detected more commonly among those with than without AF (63.6% vs 45.2%; age-sex-adjusted p&lt;0.001). There was a graded association in anticoagulant and aspirin treatment rates according to CHA2DS2-VASc score in participants with ‘known’ AF (Table). Amongst participants with ‘known’ AF, anticoagulant usage was reported by 35.7% of those with a class 1 indication for anticoagulation according to CHA2DS2-VASc score. Conclusions Opportunistic AF screening in the MMM 2022 campaign detected AF in 3.2% of participants aged ≥60, and hypertension was more common in those with AF. Over one third of detected cases were not ‘known’ cases. Only 35.7% of ‘known’ cases with a class 1 indication for anticoagulants were treated.

254. QUANTIFYING PERIOPERATIVE RISKS FOR ANTIREFLUX AND HIATUS HERNIA SURGERY: A MULTICENTER COHORT STUDY OF 4301 PATIENTS

Abstract Background Predicting perioperative risks for fundoplication and hiatus hernia repair will inform treatment decision-making, hospital resource allocation, and benchmarking. However, available risk calculators do not account for hernia anatomy or technical aspects of surgery in estimating perioperative risk. Using a comprehensive Australian cohort, we quantified the incidence and determined the independent predictors of intraoperative and postoperative complications associated with antireflux and hiatus hernia surgeries. Additionally, we performed an in-depth analysis to understand the complication profiles associated with each independent risk factor. Methods Retrospective analysis of all elective antireflux and hiatus hernia surgeries in 36 Australian hospitals over 10 years. Hierarchical multivariate logistic regression analyses were performed to determine the independent predictors of intraoperative and postoperative complications accounting for patient, surgical, anatomical, and perioperative factors. Results A total of 4301 surgeries were analyzed. Of these, 1569 (36.5%) were large/giant hernias and 292 (6.8%) were revisional procedures. The incidence rates of intra- and postoperative complications were 12.6% and 13.3%, respectively. The Charlson Comorbidity Index, hernia size, revisional surgery, and baseline anticoagulant usage independently predicted both intraoperative and postoperative complications. These risk factors were associated with their own complication profiles. Finally, using risk matrices, we visualized the cumulative impact of these four risk factors have on the development of intraoperative, overall postoperative, and major postoperative complications. Conclusions This study has improved our understanding of perioperative morbidity associated with antireflux and hiatus hernia surgery. Our findings group patients along a spectrum of perioperative risks that informs care at an individual and institutional level.

Dicloxacillin is an inducer of intestinal P-glycoprotein but neither dicloxacillin nor flucloxacillin increases the risk of stroke/systemic embolism in direct oral anticoagulant users.

We aimed to assess if dicloxacillin/flucloxacillin reduces the therapeutic efficacy of direct oral anticoagulants (DOACs) and the underlying molecular mechanism. In a randomized, crossover study, we assessed whether dicloxacillin reduces oral absorption of drugs through P-glycoprotein (P-gp) during 10 and 28 days of treatment. To study the impact of dicloxacillin/flucloxacillin on intestinal and hepatic expression of P-gp in vitro, we usd LS174T cells and 3D spheroids of primary human hepatocytes. Finally, we used nationwide Danish health registries and the UK's Clinical Practice Research Datalink to estimate hazard ratios (HRs) for the risk of stroke and systemic embolism following dicloxacillin/flucloxacillin exposure among DOAC users, using phenoxymethylpenicillin and amoxicillin as active comparators. Dicloxacillin reduced the area under the curve of dabigatran to a geometric mean ratio 10days of 0.67 (95% confidence interval [CI]: 0.42-1.1) and geometric mean ratio 28 days of 0.72 (95% CI: 0.39-1.4), suggesting reduced oral absorption via increased P-gp expression. In vitro, dicloxacillin raised P-gp expression in both intestinal and liver cells, while flucloxacillin only affected liver cells. In the pharmacoepidemiologic study, dicloxacillin and flucloxacillin were not associated with increased risk of stroke/systemic embolism (dicloxacillin vs. phenoxymethylpenicillin HR: 0.93, 95% CI: 0.72-1.2; flucloxacillin vs. amoxicillin HR: 0.89, 95% CI: 0.51-1.5). Dicloxacillin increases expression of intestinal P-gp, leading to reduced oral absorption of dabigatran. However, concomitant use of dicloxacillin/flucloxacillin was not associated with stroke and systemic embolism among DOAC users, suggesting no clinical impact from the drug-drug interaction between dicloxacillin/flucloxacillin and DOACs.

Comparison of Oral Anticoagulant Users with Non-users Admission Laboratory Parameters, Length of Hospital Stay and Outcomes in COVID-19 Infection

Comparison of Oral Anticoagulant Users with Non-users Admission Laboratory Parameters, Length of Hospital Stay and Outcomes in COVID-19 Infection

Analysis of anticoagulant use in patients with recurrent spontaneous abortion across nine Chinese cities (2016–2021)

Objective: In this study, we aimed to identify trends in anticoagulant usage among patients with recurrent spontaneous abortion (RSA), assess the appropriateness of these prescriptions, and provide recommendations for future clinical practice. Methods: We retrospectively analyzed outpatient prescription data for patients with RSA from nine Chinese cities—Beijing, Chengdu, Guangzhou, Harbin, Hangzhou, Shanghai, Shenyang, Tianjin, and Zhengzhou—over the period 2016 to 2021. Results: A total of 10,293 outpatient prescriptions were reviewed. The number of prescriptions increased annually until peaking in 2019, after which a gradual decline was observed. From 2019 to 2021, enoxaparin was the most frequently prescribed anticoagulant. Among the eight anticoagulants analyzed, enoxaparin had the highest total prescription volume and defined daily doses (DDDs), followed by dalteparin, nadroparin, and fondaparinux. The proportion of fondaparinux prescriptions rose annually, and while its defined daily cost (DDC) was consistently the highest, there was a downward trend in value. The economic benefits of most anticoagulants were aligned with their social benefits. Although the percentage of prescriptions with inappropriate indications decreased each year, it remained high at 69%. Conclusion: Enoxaparin emerged as the predominant anticoagulant for RSA treatment in the nine cities studied. Fondaparinux usage increased in clinical practice, with a decreasing trend in DDC values. The alignment of economic and societal benefits indicates good cost-effectiveness. However, there remains a need to further improve the appropriateness of prescription indications.

The Causes of Platelet Aggregation in Version 6.4 Trima Accel Automated Blood Collection System and the Comparison of Two Intervention Measures

To explore the causes of platelet aggregation in version 6.4 Trima Accel automated blood collection system and the effect of 2 intervention measures. The data on platelet aggregation (n=61) and non-aggregation (n=323) of 61 donors in 2020 were collected and the causes of aggregation were analyzed. Then the 72 donors with platelet aggregation in 2021 were randomized into intervention group A (increasing the anticoagulant-to-blood ratio) and intervention group B (wrapping the donor's arm with an electric blanket to keep warm and improve the blood flow speed). The collection time, average blood flow speed, number of machine alarms, anticoagulant usage, deaggregation and citrate reaction of the two groups were compared. Platelet aggregation was negatively correlated with the average blood flow speed (r =-0.394) and positively correlated with the collection time (r =0.458). The equations for predicting aggregation and non-aggregation were constructed based on Bayesian and Fisher discriminant analysis, and the predicted accuracy was 77.1%. The comparison of the effects of two intervention measures showed that the average blood flow speed in group B was higher than that in group A; the collection time, number of machine alarms, anticoagulant usage and proportion of citrate reaction in blood donors in group B were all lower than those in Group A, all these differences were significant (P < 0.05). In the entire cohort in 2021, 90.28% of the products were immediately deaggregated after collection, and 9.72% of the products were deaggregated within 4 hours. There was no statistically significant difference in deaggregation between the two intervention groups (P >0.05). During apheresis platelet collection, the predictive equations for aggregation and non-aggregation can be used to predict the occurrence probability of aggregation, and the intervention can be made in advance. Both intervention measures are effective in reducing platelet aggregation, however, measure B has the advantages of improving the speed of blood collection, shortening the collection time, reducing the alarm frequency and the anticoagulant usage, and reducing the incidence of citrate reaction in blood donors.