The Prevalent New-User Design to Study Drug-Drug Interactions: The Example of Sulfonylureas and Warfarin Interaction on the Risk of Severe Hypoglycemia.

PURPOSE: The optimal design for pharmacoepidemiologic drug-drug interactions (DDIs) studies is unclear. Using the association between concomitant use of sulfonylureas and warfarin and the risk of severe hypoglycemia as a case study, a DDI with little or no clinical impact, we tested whether the prevalent new-user design can be applied in the area. METHODS: Among all patients initiating sulfonylureas in the UK's Clinical Practice Research Datalink (1998-2020), we identified those adding-on warfarin while on a sulfonylurea. For each co-exposed patient, we defined a prescription-based exposure set including other sulfonylurea users not adding-on warfarin (comparators). Within each exposure set, we matched each co-exposed patient to five comparators on time-conditional propensity scores (TCPS) and followed them using an as-treated approach. Cox proportional hazards models estimated hazard ratios (HRs) and 95% confidence intervals (CIs) of severe hypoglycemia associated with concomitant use of sulfonylureas and warfarin compared to use of sulfonylureas alone. Sensitivity analyses addressed the impact of different potential sources of bias. RESULTS: The study cohort included 17 890 patients co-exposed to sulfonylureas and warfarin and 88 749 matched comparators. After TCPS matching, patient characteristics were well-balanced between groups. Compared to use of sulfonylureas alone, concomitant use of sulfonylureas and warfarin was not associated with the risk of severe hypoglycemia (HR, 1.04; 95% CI, 0.92-1.17). Sensitivity analyses were consistent with the primary analysis (HRs ranging from 1.01 to 1.15, all not statistically significant). CONCLUSIONS: Our study suggests that the prevalent new-user design could be used for the assessment of clinical effects of DDIs.

Safety and efficacy of apixaban versus warfarin in peritoneal dialysis patients with non-valvular atrial fibrillation: protocol for a prospective, randomised, open-label, blinded endpoint trial (APIDP2).

INTRODUCTION: Several randomised controlled trials have demonstrated that novel oral anticoagulants are safer compared with vitamin K antagonists for the management of non-valvular atrial fibrillation (NVAF) to prevent thromboembolic events in the general population. There is a growing interest in the use of apixaban in patients with end-stage renal disease (ESRD) undergoing peritoneal dialysis (PD) but there is a lack of randomised data in this population. METHODS AND ANALYSIS: APIDP2 is a prospective parallel, randomised, open-label, blinded endpoint trial involving patients with ESRD undergoing chronic PD who have NVAF. A total of 178 participants will be recruited from 20 French PD centres. Eligible patients will be randomly assigned to receive either apixaban at a reduced dose of 2.5 mg two times per day (dose determined with the previous pharmacokinetic study APIDP1) or dose-adjusted to international normalised ratio (INR) target (2-3) coumadin therapy. Anticoagulation to prevent thromboembolic events will be initiated or changed according to the randomisation for a duration of 1 year. The primary outcome is a major or clinically relevant non-major bleeding from randomisation up to month 12, assessed according to the International Society on Thrombosis and Haemostasis Score. Secondary outcomes encompass an efficacy composite criterion combining stroke or transient ischaemic attack (TIA), cardiovascular death and thrombosis including myocardial infarction cumulated at 12 months. Bleeding events will be also classified according to Global Use of Strategies to Open Occluded Coronary Arteries (GUSTO) and Thrombolysis In Myocardial Infarction (TIMI) criteria and pharmacodynamics outcomes will evaluate the time within the INR target range of 2-3 in the warfarin arm over 1 year, and anti-Xa apixaban activity in case of bleeding events and at 1 month, 6 months and 12 months of follow-up in the apixaban arm. To demonstrate that apixaban is safer than warfarin at 1 year, assuming two interim analyses after 60 and 118 patients, a bilateral alpha risk of 5% and a power of 80%, 178 patients are needed in this randomised trial (effect size found from the Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation (ARISTOTLE) Study among patients with creatinine clearance 25-30 ml/min), that is, 89 patients per group. ETHICS AND DISSEMINATION: The study has been approved by the ethics committee Comité de Protection des Personnes Sud Est III - Lyon - FRANCE, CT number 2023-507544-37-00. Written informed consent is required for each participant. Findings will be presented at scientific meetings and published in peer-reviewed journals. TRIAL REGISTRATION: ClinicalTrials.gov, NCT06045858; European Clinical Trial System, CT number 2023-507544-37-00.

Direct Oral Anticoagulants in Antiphospholipid Syndrome-Associated Venous Thromboembolism: Real World Evidence.

BACKGROUND: The efficacy and safety of direct oral anticoagulants (DOACs) versus warfarin in patients with antiphospholipid syndrome-associated venous thromboembolism (APS-VTE) remain uncertain. We aimed to evaluate efficacy and safety of DOACs in patients with APS-VTE. METHODS: Using the Korean Health Insurance Review and Assessment Service database, we retrospectively identified all APS-VTE cases. We examined the VTE recurrence, arterial thrombosis, death and bleeding in patients who received DOACs compared with warfarin for therapeutic anticoagulation. RESULTS: Of all the VTE cases (n = 84,916) detected between 2014 and 2018, patients with APS-VTE (n = 410) accounted for 0.48%. Most patients with APS-VTE (73%) were aged < 60 years. The recurrent VTE occurred in 8 of 209 patients (3.8%) who received DOACs and in 7 of 201 (3.5%) who received warfarin (relative risk [RR], 1.099; 95% confidence interval [CI], 0.41-2.98; P = 1.000). The arterial thrombosis (ATE) occurred in 8 of 209 patients (3.8%) who received DOAC and in 20 of 201 (10%) who received warfarin (RR, 0.385; 95% CI, 0.17-0.85; P = 0.024). The composite outcomes of VTE recurrence, ATE, or mortality were significantly lower in patients (9.1%) on DOAC than in those (16.3%) on warfarin (RR, 0.537; 95% CI, 0.32-0.91; P = 0.028). The bleeding outcome occurred in 7 of 209 (3.4%) patients in the DOACs group and 7 of 201 (3.5%) patients in the warfarin group (RR, 0.96; 95% CI, 0.34-2.69; P = 0.840). CONCLUSION: In patients with APS-VTE, DOACs group showed comparable rates of recurrent VTE, bleeding, and deaths, but a significantly lower incidence of ATE and composite outcomes compared with the warfarin group in Korea.

Application Value and Safety Analysis of Warfarin, Rivaroxaban, and Dabigatran Ester in Elderly Patients With Atrial Fibrillation.

BACKGROUND: This study aimed to evaluate the application value and safety of Warfarin, Rivaroxaban, and Dabigatran in elderly patients with atrial fibrillation. METHODS: A total of 180 elderly patients with atrial fibrillation admitted to our hospital were retrospectively analyzed. According to their anticoagulant treatment regimen, patients were divided into three groups: Warfarin (57 cases), Rivaroxaban (61 cases), and Dabigatran (62 cases). General demographic information was collected, and coagulation function indicators-including fibrinogen (FIB), thrombin time (PT), activated partial thrombin time (APTT), and D-dimer (D-D)-as well as liver function indexes-including total bilirubin (TbiL), alkaline phosphatase (ALP), aspartate aminotransferase (AST), and alanine transferase (ALT)-were compared before and after 4 weeks of treatment. RESULTS: There were no significant differences in demographic characteristics such as gender, age, body mass index, or disease course among the three groups. The total effective rate in the Warfarin group (84.21%) was significantly lower than in the Rivaroxaban (98.36%) and Dabigatran (96.77%) groups (p < 0.05). However, there was no significant difference in the total effective rate between the Rivaroxaban and Dabigatran groups (p > 0.05). Additionally, no significant differences were found in the effects of the three drugs on coagulation function, liver function, or the incidence of bleeding (p = 0.052). CONCLUSION: Warfarin, Rivaroxaban, and Dabigatran can effectively prevent thrombosis in elderly patients with atrial fibrillation, with Rivaroxaban and Dabigatran showing superior effectiveness. All three drugs demonstrated similar low rates of bleeding events and had no significant impact on coagulation and liver function.

Prospective Monitoring of New Drugs in Older Adults with and without Frailty: Near-Real-Time Assessment of Effectiveness and Safety of Oral Anticoagulants in Medicare Data.

BACKGROUND AND OBJECTIVE: Prospective sequential analyses after a new drug approval allow proactive surveillance of new drugs. In the current study, we demonstrate feasibility of frailty-specific sequential analyses for dabigatran, rivaroxaban, and apixaban versus warfarin. METHODS: We partitioned Medicare data from 2011 to 2020 into datasets based on calendar year following the date of drug approval. Each calendar year of data was added sequentially for analysis. We used a new-user, active comparative design by comparing the initiators of dabigatran versus warfarin, rivaroxaban versus warfarin, and apixaban versus warfarin. Patients aged ≥ 65 years with atrial fibrillation without contraindication to the anticoagulants were included. Claims-based frailty index ≥ 0.25 was used to define frailty. The initiators of each direct oral anticoagulant were propensity-score matched to the initiators of warfarin within each frailty status. The effectiveness outcome was ischemic stroke or systemic thromboembolism, and the safety outcome was major bleeding. For each calendar year, we estimated hazard ratios (HRs) and 95% confidence intervals (CIs) from Cox proportional hazards models using all data available up to that year. RESULTS: As an example of the results, in the 2020 dataset, compared with warfarin, apixaban was associated with a reduced risk of ischemic stroke or systemic thromboembolism (frail: HR 0.73, 95% CI 0.63-0.85; non-frail: HR 0.65, 95% CI 0.59-0.72) and major bleeding (frail: HR 0.63, 95% CI 0.57-0.69; non-frail: HR 0.59, 95% CI 0.56-0.63) in both frail and non-frail patients. We found evidence for apixaban's effectiveness and safety within 1-2 years after the drug approval in frail older patients. CONCLUSION: Our frailty-specific sequential analyses can be applied to future near-real-time monitoring of newly approved drugs.

Extended anticoagulation after venous thromboembolism.

INTRODUCTION: Venous thromboembolism (VTE) carries a high risk of recurrence, and this risk is strongly related to the nature of the index event. Thus, extended anticoagulation treatment is recommended for patients with a high recurrence risk and should be considered for patients with an intermediate risk. This study aimed to provide insight into the clinical practice of extended anticoagulation for VTE patients METHODS. This was a retrospective study of VTE patients covering the period from January 2020 through June 2021. We categorised patients by their estimated risk of recurrence as low (less-than 3% per year), intermediate (3-8% per year) or high (> 8% per year). The decision to stop or extend anticoagulation was made in a multidisciplinary VTE clinic. RESULTS: A total of 343 patients were included; 315 patients were eligible for analysis. The majority of patients (58.7%) had an intermediate recurrence risk. In total 80.3% received extended treatment. The use was highest (97.9%) among patients with a high recurrence risk, whereas 82.7% with an intermediate risk and 15.2% with a low risk received extended therapy. Non-vitamin K antagonist oral anticoagulants were preferred for extended therapy (82.2%), whereas 5.1% received warfarin and 12.6% low molecular weight heparin. CONCLUSIONS: In this real-world clinic, the majority of VTE patients switched to extended treatment after initial standard anticoagulation. The role of patient and physician preference as determinants driving this decision should be investigated further. FUNDING: This study received an unrestricted grant from Bayer, which had no involvement in the study design, data collection, analysis, or manuscript preparation. TRIAL REGISTRATION: Not relevant.

Comparison of oral anticoagulants for stroke prevention in atrial fibrillation using the UK clinical practice research Datalink Aurum: A reference trial (ARISTOTLE) emulation study.

BACKGROUND: Stroke prevention guidance for patients with atrial fibrillation (AF) uses evidence generated from randomised controlled trials (RCTs). However, applicability to patient groups excluded from trials remains unknown. Real-world patient data provide an opportunity to evaluate outcomes in a trial analogous population of direct oral anticoagulants (DOACs) users and in patients otherwise excluded from RCTs; however, there remains uncertainty on the validity of methods and suitability of the data. Successful reference trial emulation can support the generation of evidence around treatment effects in groups excluded or underrepresented in trials. We used linked United Kingdom primary care data to investigate whether we could emulate the pivotal ARISTOTLE trial (apixaban versus warfarin) and extend the analysis to investigate the impact of warfarin time in therapeutic range (TTR) on results. METHODS AND FINDINGS: Patients with AF in the UK Clinical Practice Research Datalink (CPRD Aurum) prescribed apixaban or warfarin from 1 January 2013 to 31 July 2019 were selected. ARISTOTLE eligibility criteria were applied to this population and matched to the RCT apixaban arm on baseline characteristics creating a trial-analogous apixaban cohort; this was propensity-score matched to warfarin users in the CPRD Aurum. ARISTOTLE outcomes were assessed using Cox proportional hazards regression stratified by prior warfarin exposure status during 2.5 years of patient follow-up and results benchmarked against the trial results before treatment effectiveness was further evaluated based on (warfarin) TTR. The dataset comprised 8,734 apixaban users and propensity-score matched 8,734 warfarin users. Results [hazard ratio (95% confidence interval)] confirmed apixaban noninferiority for stroke or systemic embolism (SE) [CPRD 0.98 (0.82,1.19) versus trial 0.79 (0.66,0.95)] and death from any cause [CPRD 1.03 (0.93,1.14) versus trial 0.89 (0.80,0.998)] but did not indicate apixaban superiority. Absolute event rates for stroke/SE were similar for apixaban in CPRD Aurum and ARISTOTLE (1.27%/year), whereas a lower event rate was observed for warfarin (CPRD Aurum 1.29%/year, ARISTOTLE 1.60%/year). Analysis by TTR suggested similar effectiveness of apixaban compared with poorly controlled warfarin (TTR < 0.75) for stroke/SE [0.91 (0.73, 1.14)], all-cause death [0.94 (0.84, 1.06)], and superiority for major bleeding [0.74 (0.63, 0.86)]. However, when compared with well-controlled warfarin (TTR ≥ 0.75), apixaban was associated with an increased hazard for all-cause death [1.20 (1.04, 1.37)], and there was no significant benefit for major bleeding [1.08 (0.90, 1.30)]. The main limitation of the study's methodology are the risk of residual confounding, channelling bias and attrition bias in the warfarin arm, and selection bias and misclassification in the analysis by TTR. CONCLUSIONS: Analysis of noninterventional data generated results demonstrating noninferiority of apixaban versus warfarin consistent with prespecified benchmarking criteria. Unlike in ARISTOTLE, superiority of apixaban versus warfarin was not seen, possible due to the lower proportion of Asian patients and higher proportion of patients with well-controlled warfarin compared to ARISTOTLE. This methodological template can be used to investigate treatment effects of oral anticoagulants in patient groups excluded from or underrepresented in trials and provides a framework that can be adapted to investigate treatment effects for other conditions.

Effect of Vascular Senescence on the Efficacy and Safety of Warfarin: Insights from Rat Models and a Prospective Cohort Study.

Warfarin, with its narrow therapeutic range, requires the understanding of various influencing factors for personalized medication. Vascular senescence, marked by vascular stiffening and endothelial dysfunction, has an unclear effect on the efficacy and safety of warfarin. Based on previous studies, we hypothesized that vascular senescence increases the risk of bleeding during warfarin therapy. This study aimed to explore these effects using animal models and clinical cohorts. We established rat models of vascular senescence and calcification using d-galactose, vitamin D, and nicotine. After validating the models, we examined changes in the international normalized ratio (INR) at fixed warfarin doses (0.20 and 0.35 mg/kg). We found that vascular senescence caused significantly elevated INR values and increased bleeding risk. In the prospective clinical cohort study (NCT06428110), hospitalized warfarin patients with standard dose adjustments were divided into vascular senescence and control groups based on ultrasound and computed tomography diagnosis. Using propensity score matching to exclude the influence of confounding factors, we found that the vascular senescence group had lower steady-state warfarin doses and larger dose adjustments, with a higher probability of INR exceeding the therapeutic range. The vascular senescence group tended to experience more bleeding or thromboembolic/ischemic events during 1 year of follow-up, while there was no statistical difference. In conclusion, vascular senescence leads to unstable INR values and increases higher bleeding risk during warfarin therapy, highlighting the importance of considering vascular senescence in future precision warfarin therapies. SIGNIFICANCE STATEMENT: Many factors influence warfarin efficacy; however, the effect of vascular senescence remains unclear. This study aimed to investigate the effects of vascular senescence on the efficacy and safety of warfarin. Through both rat models and clinical cohort studies, our findings indicated that vascular senescence may compromise the stability of warfarin, presenting challenges in maintaining its efficacy and safety.

Quality of Life of Patients Receiving Warfarin Therapy at a Tertiary Care Centre in Indonesia Using DASS (Duke Anticoagulation Satisfaction Scale).

Purpose: This study aimed to examine the quality of life of patients receiving warfarin therapy at Dr. Hasan Sadikin Central General Hospital, and its relationship with demographic factors. Patients and Methods: The procedures started with the submission of a study permit, followed by validation of the Duke Anticoagulation Satisfaction Scale (DASS) questionnaire. In addition, the validated questionnaire was completed by the participants, and significant variables were analyzed using the chi-square method for multivariate analysis. Results: The results showed that the questionnaire was valid and could be used for further analyses. Among the 88 selected participants, 52 and 36 had scoring categories <56.266 and 56.266 ≤ x ≤ 143.734, respectively, with no patients having a scoring category > 143.734. In addition, participants with low education and aged ≥ 52 years were 4.916 and 3.161 times more at risk of having quality of life score of 56.266 ≤ x ≤ 143.734, respectively. Based on the results, the average quality of life score of patients was 59.66. Participants with low educational levels and those aged ≥ 52 years were at a higher risk of having quality of life score of 56.266 ≤ x ≤ 143.734. Conclusion: In summary, a lower quality of life score was linked to increased comfort and satisfaction among patients receiving warfarin treatment. Additionally, these patients experienced fewer feelings of limitations and inconveniences related to their treatment plans.

Incidence and Impact on Quality of Life of Heavy Menstrual Bleeding in Women on Oral Anticoagulant Therapy.

INTRODUCTION: Heavy menstrual bleeding affects up to two thirds of women on oral anticoagulation. The rates of heavy menstrual bleeding, its impact on quality of life and associated risk factors in women attending anticoagulation clinics in South Africa are largely unknown. MATERIALS AND METHODS: A prospective cohort study was performed over an eight-month period in women on Warfarin (n = 30) and Rivaroxaban (n = 27) for a median [interquartile range] duration of 15.5 [78.0] months attending an anticoagulation clinic in Johannesburg, South Africa. Heavy menstrual bleeding was assessed over one menstrual cycle using the validated pictorial blood loss assessment charts (PBAC) and the menstrual bleeding questionnaire (MBQ). RESULTS: In this population of predominantly African ethnicity, with a median age of 39 [8] years, 39 (68.4%) women experienced heavy menstrual bleeding, defined as a PBAC score of >100. Median cycle length on anticoagulation and MBQ scores were significantly higher among women with a PBAC score of >100 (p > 0.05). Univariate analysis identified Rivaroxaban as a risk factor for heavy menstrual bleeding (OR 5.03, 95% CI 1.40-18.12). Heavy menstrual bleeding required treatment in 29 (74.4%) women which included management of iron deficiency, anti-fibrinolytics, modification of anticoagulation and hormonal contraception. CONCLUSION: Heavy menstrual bleeding was associated with a considerable negative impact on quality of life. This was most significant for women on Rivaroxaban as compared to Warfarin. It is essential to monitor and appropriately treat heavy menstrual bleeding in at risk women on anticoagulant treatment.

Vitamin-K antagonist versus dual antiplatelet therapy in management of isolated and non-obstructive atherosclerotic coronary artery ectasia.

BACKGROUND: Treatment of isolated and non-obstructive atherosclerotic coronary artery ectasia (CAE) is still controversial. AIM: To assess the efficacy and safety of vitamin-K antagonist (VKA) versus dual antiplatelet (DAPT) therapy in management of patients with isolated and non-obstructive atherosclerotic CAE. METHODS: We prospectively enrolled 79 patients diagnosed on elective coronary angiography to have either isolated CAE or non-obstructive atherosclerotic CAE. Patients were assigned in 1:1 pattern to receive either VKA (warfarin) or DAPT (aspirin plus clopidogrel). Patients were followed-up for nine-months. The primary endpoint was the cumulative events rate including acute coronary event, target vessel intervention, or cardiac death. Analysis of cumulative events at different time intervals, its individual components, and bleeding were considered secondary endpoints. RESULTS: Cumulative events rate was 33%, with mortality rate of 2.5%. Both treatment groups showed comparable cumulative events during the nine-months follow-up duration. Nevertheless, Kaplan-Meier analysis beyond the first 3-months of follow-up showed significantly higher event-free survival among the VKA-group. Recurrent events (≥2) were significantly higher among the DAPT-group. Both groups showed no major bleeding events. Multivariable cox-regression analysis showed that presence of significant coronary tortuosity, use of DAPT in reference to VKA, and lower percent time in therapeutic range (%TTR) among those receiving VKA were significant independent predictors of clinical adverse events beyond the first 3-months of follow-up. CONCLUSION: Cumulative adverse events were comparable among both treatment groups for isolated non-obstructive CAE. However, adverse events were significantly more frequent in the DAPT-group beyond the first three months.

Peri-operative Anticoagulation Strategies, Bleeding and Thrombotic Complications in Pediatric Patients Undergoing Intervention for Congenital Portosystemic Shunts.

BACKGROUND: Congenital portosystemic shunts (CPSS) are rare congenital abnormalities causing abnormal blood flow between the portal vein and systemic circulation. This study reports on the peri-operative anticoagulation management of CPSS patients post closure, focusing on the incidence of thrombotic and bleeding complications. METHODS: This is a single-center retrospective analysis of CPSS patients who underwent surgery or endovascular intervention between 2005 and 2021. The protocol included unfractionated heparin (UFH) during and immediately after surgery, followed by either warfarin or low molecular weight heparin (LMWH) postoperatively. Outcomes assessed included postoperative thrombotic and bleeding complications. RESULTS: A total of 44 patients were included. Postoperatively, 89% received treatment-dose UFH, transitioning to warfarin or LMWH at discharge. Thrombotic complications occurred in 16% of patients, predominantly in the superior mesenteric vein. Surgical interventions and continuous infusion of tissue plasminogen activator (tPA) were used for clot resolution. Bleeding complications were observed in 64% of patients, primarily managed with transfusions and temporary UFH interruption. No deaths related to thrombotic, or bleeding events were reported. CONCLUSIONS: Our findings underscore the delicate balance required in anticoagulation management for CPSS patients, revealing an occurrence of both thrombotic and bleeding complications postoperatively. LEVELS OF EVIDENCE: Level II, retrospective study.

Reprint of: Efficacy and safety of apixaban compared to warfarin for nonvalvular atrial fibrillation in end-stage renal disease on hemodialysis.

BACKGROUND: This study compared the efficacy and safety of apixaban and warfarin in patients with nonvalvular atrial fibrillation (NVAF) and end-stage renal disease (ESRD) on hemodialysis (HD). Apixaban decreased incidence of stroke and bleeding compared with warfarin in major clinical trials that excluded patients with severe renal dysfunction. Apixaban is no longer contraindicated in patients with ESRD on HD with NVAF based on pharmacokinetic studies. Limited clinical data exist for patients with ESRD on HD on apixaban. METHODS: A retrospective chart review was performed on patients with a diagnosis of NVAF and ESRD on HD who were prescribed apixaban or warfarin for stroke prevention in the years 2018 through 2019. Patients' charts were reviewed for up to a 2-year period. Patients on renal replacement therapy other than HD, those using anticoagulation for reasons other than NVAF, patients with Child-Pugh Class C cirrhosis, and those with severe mitral valve stenosis were excluded. The primary outcome was emergency department visits or hospital admissions for ischemic stroke or transient ischemic attack. Secondary outcomes included major or minor bleeding and adverse effects. RESULTS: A total of 181 patients were screened; 110 patients met eligibility criteria and were included in the analysis. Four patients (7.5%) in the apixaban group and 6 patients (10.5%) in the warfarin group met the primary outcome of hospitalization or emergency department visit for stroke (P = 0.742). Symptomatic bleeding occurred in 39.6% of patients in the apixaban group and 36.8% in the warfarin group (P = 0.918). A trend in major bleeding occurred more often in the warfarin group, 52.4% versus 49.2% (P = 0.758). CONCLUSIONS: There were no statistically significant differences in efficacy and safety outcomes between apixaban and warfarin in patients with NVAF and ESRD on HD in the intention-to-treat analysis of our study. Larger trials are needed to further analyze this patient population.

Effect of different anticoagulants and antiplatelets on intraoral bleeding time during professional oral hygiene session.

OBJECTIVE: Patients with thromboembolic problems, prosthetic valves, or coagulation issues are commonly prescribed anticoagulants and antiplatelets. Anticoagulant and antiplatelet medication might constitute a challenge for dentists and dental hygienists since possible prolonged bleeding might interfere with dental procedures. The aim of the present study was to examine the bleeding durations associated with various anticoagulants and antiplatelets during professional dental hygiene sessions, utilizing a modified Ivy test adapted for the oral context. MATERIALS AND METHODS: Ninety-three consecutive patients undergoing professional oral hygiene were recruited. Debridement during oral hygiene was performed using ultrasonic mechanical instrumentation, and bleeding sites were assessed and treated with gentle pressure using sterile gauzes. The time for bleeding cessation was recorded. Patients were categorized into six groups based on their drug intake, Control: no anticoagulants or antiplatelets DTI: direct thrombin inhibitors (dabigatran) AntiXa: directa factor Xa inhibitors (endoxaban, apixaban, rivaroxaban) VKA: vitamin K antagonists (warfarin, acenocoumarol) SAPT: single anti-platelet therapy (acetylsalicylic acid or clopidogrel) DAPT: dual anti-platelet therapy (acetylsalicylic acid and clopidogrel). Bleeding time was measured in seconds and mean values were assessed among the different groups. Differences between groups were investigated with Kruskal-Wallis test followed by Dunn's post-hoc correction for multiple comparisons or two-way ANOVA followed by Dunnett post-hoc; RESULTS: Control patients presented the lowest bleeding time 50 s, followed by AntiXa (98), SAPT (105), DTI (120), DAPT (190) and VKA (203). A statistically significant difference was present among control and DTI (p = 0.004), VKA (p < 0.001), DAPT (p < 0.001). CONCLUSIONS: Based on the present outcomes, an increased risk of prolonged bleeding emerged in patients taking VKA and DAPT. CLINICAL SIGNIFICANCE: bleeding did not interfere with the oral hygiene session The optimal period for dental treatment of these patients should be 2-3 h before the next dose, without the need to temporarily suspend the medication.

Prognosis of Patients With Ischemic Stroke With Prior Anticoagulant Therapy: Direct Oral Anticoagulants Versus Warfarin.

BACKGROUND: Direct oral anticoagulants (DOACs) have been the drug of choice for preventing ischemic stroke in patients with atrial fibrillation since 2014. In previous studies, the stroke risk while taking warfarin was 2 per 100 patient-years and 1.5% per year while taking DOACs. We hypothesized that even if ischemic stroke occurred during anticoagulation therapy with DOACs, the prognosis was likely to be better than that with warfarin. METHODS AND RESULTS: Data from 2002 to 2019, sourced from a nationwide claims database, were used to identify atrial fibrillation patients using International Classification of Diseases codes. Patients who experienced an ischemic stroke during anticoagulation were categorized by the drugs used (warfarin, dabigatran, apixaban, rivaroxaban, and edoxaban). The primary outcome was mortality within 3 months and 1 year after the ischemic stroke. Among the 9578 patients with ischemic stroke during anticoagulation, 3343 received warfarin, and 6235 received DOACs (965 dabigatran, 2320 apixaban, 1702 rivaroxaban, 1248 edoxaban). The DOACs group demonstrated lower risks of 3-month (adjusted hazard ratio [HR], 0.550, [95% CI, 0.473-0.639]; P<0.0001) and 1-year mortality (adjusted HR, 0.596 [95% CI, 0.536-0.663]; P<0.0001) than the warfarin group. Apixaban and edoxaban within the DOAC group exhibited particularly reduced 1-year mortality risk compared with other DOACs (P<0.0001). CONCLUSIONS: Our study confirmed that DOACs have a better prognosis than warfarin after ischemic stroke. The apixaban and edoxaban groups had a lower risk of death after ischemic stroke than the other DOAC groups.

Risk of Major Bleeding, Stroke/Systemic Embolism, and Death Associated With Different Oral Anticoagulants in Patients With Atrial Fibrillation and Severe Chronic Kidney Disease.

BACKGROUND: Patients with atrial fibrillation and severe chronic kidney disease have higher risks of bleeding, thromboembolism, and mortality. However, optimal anticoagulant choice in these high-risk patients remains unclear. METHODS AND RESULTS: Using deidentified electronic health records from the Optum Labs Data Warehouse, adults with atrial fibrillation and severe chronic kidney disease (estimated glomerular filtration rate <30 mL/min per 1.73 m2) initiating warfarin, apixaban, or rivaroxaban between 2011 and 2021 were included. Using inverse probability of treatment weighting, adjusted risks of major bleeding, stroke/systemic embolism, and death were compared among agents. A total of 6794 patients were included (mean age, 78.5 years; mean estimated glomerular filtration rate, 24.7 mL/min per 1.73 m2; 51% women). Apixaban versus warfarin was associated with a lower risk of major bleeding (incidence rate, 1.5 versus 2.9 per 100 person-years; subdistribution hazard ratio [sub-HR], 0.53 [95% CI, 0.39-0.70]), and similar risks for stroke/systemic embolism (incidence rate, 1.9 versus 2.4 per 100 person-years; sub-HR, 0.80 [95% CI, 0.59-1.09]) and death (incidence rate, 4.6 versus 4.5 per 100 person-years; HR, 1.03 [95% CI, 0.82-1.29]). Rivaroxaban versus warfarin was associated with a higher risk of major bleeding (incidence rate, 4.9 versus 2.9 per 100 person-years; sub-HR, 1.65 [95% CI, 1.10-2.48]), with no difference in risks for stroke/systemic embolism and death. Apixaban versus rivaroxaban was associated with a lower risk of major bleeding (sub-HR, 0.53 [95% CI, 0.36-0.78]). CONCLUSIONS: These real-world findings are consistent with potential safety advantages of apixaban over warfarin and rivaroxaban for patients with atrial fibrillation and severe chronic kidney disease. Further randomized trials comparing individual oral anticoagulants are warranted.

Early anti-coagulation therapy in new-onset atrial fibrillation after coronary artery bypass grafting: a randomized trial pilot study.

BACKGROUND: New-onset postoperative atrial fibrillation (POAF) is a common complication after coronary artery bypass grafting (CABG) surgery, increasing the risk of embolism and stroke. There is a lack of information on the use of anticoagulants in this context. The choice between Warfarin and Direct oral anticoagulants (DOACs) also is not well-established. This randomized study aimed to compare the feasibility and safety of Warfarin and Rivaroxaban in preventing thrombotic events in POAF patients after isolated CABG. METHODS: A total of 66 patients were randomized parallelly with 1:1 allocation to receive either Rivaroxaban (n = 34) or Warfarin (n = 32). Major bleeding events within 30 days after discharge were the primary outcome. Secondary outcomes included minor bleeding events and thrombotic episodes. Clinical characteristics, medication regimens, and left atrial diameter were assessed. Statistical analyses were performed using appropriate tests. RESULTS: No thrombotic episodes were observed in either treatment arm. No major bleeding events occurred in either group. Four minor bleeding events were reported, with no significant difference between the treatment groups (P = 0.6). Patients with atrial fibrillation had significantly larger left atrial diameters compared to those with normal sinus rhythm (40.5 vs. 37.8 mm, P = 0.01). CONCLUSIONS: This pilot study suggests that Warfarin and Rivaroxaban are both safe and effective for preventing thrombotic episodes in POAF patients after isolated CABG. No significant differences in major bleeding events were observed between the two anticoagulants. These findings may support the preference for DOACs like Rivaroxaban due to their convenience and easier maintenance. TRIAL REGISTRATION: Number IRCT20200304046696N1, Date 18/03/2020 https//irct.behdasht.gov.ir/ .

A pilot study of safety and efficacy comparison of low molecular heparin calcium sequential oral anticoagulants in the treatment of cirrhotic portal vein thrombosis.

BACKGROUND: The objective of this study is to compare and assess the efficacy and safety of low-molecular-weight heparin calcium (LMWH-Ca), followed by either warfarin or rivaroxaban, as treatment options for portal vein thrombosis (PVT) in patients with cirrhosis. METHODS: In this pilot study, cirrhotic (with liver function score of Child-Pugh A) patients diagnosed with PVT who were not on anticoagulant therapy received 2 weeks of subcutaneous injections of LMWH-Ca. They were then randomized to either warfarin (a full course of oral warfarin for 6 months) or rivaroxaban (a full course of oral rivaroxaban for 2 months), with 30 cases in each group. After a treatment period of up to 6 months, a comparative analysis was performed to assess the efficacy and safety of both groups. Volumetric changes in PVT were monitored dynamically using enhanced computed tomography scans before treatment at week 2 and month 6. RESULTS: There were no statistically significant differences in the clinical characteristics of the patients between the two groups. Rivaroxaban treatment reduced PVT median volume from 1.83 cm3 at week 2 to 0.0 cm3 at month 6 and prevented the worsening of PVT after 6 months of treatment with LMWH-Ca (P < 0.001). On the other hand, warfarin treatment increased PVT median volume from 1.95 cm3 at week 2 to 3.78 cm3 at month 6 (P = 0.002). None of the 30 patients in the rivaroxaban group had clinically significant gastrointestinal bleeding, while 2 of the 30 patients (7%) in the warfarin group had gastrointestinal bleeding (P = 0.317). CONCLUSION: Rivaroxaban followed by LMWH-Ca is an effective anticoagulant treatment strategy for PVT in cirrhosis.

The comparative efficacy and safety of factor Xa inhibitors and warfarin for primary thromboprophylaxis in multiple myeloma patients undergoing immunomodulatory therapy.

There are limited data on the optimal choice of anticoagulation in multiple myeloma (MM) patients receiving immunomodulatory drugs (IMiDs). We conducted a propensity score-matched cohort study using the TriNetX database to compare the efficacy and safety of factor Xa inhibitors and warfarin in this patient population. Compared to warfarin, factor Xa inhibitors had a similar risk of deep vein thrombosis (hazard ratio [HR]: 1.11 [95% CI: 0.50-2.46]) or pulmonary embolism (HR: 1.08 [95% CI: 0.59-2.00]). There were no differences in the risk of gastrointestinal or intracranial bleeding. Factor Xa inhibitor-treated patients had lower all-cause mortality (HR: 0.56 [95% CI: 0.36-0.86]) compared with warfarin. These data suggest that factor Xa inhibitors had similar safety and efficacy compared with warfarin for MM patients on IMiDs.

'X' marks the spot! Utilising factor Xa inhibitors to optimise thromboprophylaxis in multiple myeloma.

Venous thromboembolism (VTE) remains a significant cause of morbidity and mortality among multiple myeloma patients. Chang and colleagues' findings indicate that factor Xa inhibitors are as effective as warfarin in preventing VTE without raising the risk of gastrointestinal or intracranial bleeding complications. Commentary on: Chang et al. The comparative efficacy and safety of factor Xa inhibitors and warfarin for primary thromboprophylaxis in multiple myeloma patients undergoing immunomodulatory therapy. Br J Haematol 2024;205:473-477.