Efficacy and safety of direct oral factor Xa inhibitors compared with warfarin in patients with morbid obesity: a single-centre, retrospective analysis of chart data

Direct Oral Anticoagulants: Probability of Recurrent Venous Thromboembolism and Bleeding Risk in an Obese Population

BACKGROUND

Direct-acting oral anticoagulants (DOACs) have become the preferred drugs for managing venous thromboembolism (VTE). Despite their advantages over vitamin K antagonists such as warfarin, their use in obese patients remains controversial with many providers reluctant to switch patients managed on warfarin. Outcome research that opts to increase provider confidence when prescribing DOACs for patients with obesity will be invaluable.

OBJECTIVE

This investigation evaluated whether patients with a body mass index (BMI) 35 kg/m2 or greater who were prescribed a DOAC had a higher risk for a recurrent VTE or bleed event relative to warfarin.

METHODS

The study was conducted in West Virginia which has the highest rate of obesity in the United States.

RESULTS

Of the total study population (1633), 2.3% (37) had a recurrent thrombotic event, 5.5% (89) had a major bleed event, and 10.7% (174) had some type of bleeding event. No individual patient characteristic was associated with recurrent thrombosis-including BMI. Older age, antiplatelet use, and taking a medication with a theoretical risk of increasing the effect of DOACs were associated with any and major bleeding events. The use of warfarin was associated with major bleeding events more frequently versus a DOAC. Body mass index was not a predictor for recurrent VTE or any bleed or major bleed events.

CONCLUSIONS

These findings support the conclusion that DOACs are an appropriate and effective drug class for the management of VTE in patients with obesity.

Anticoagulation and compression therapy for proximal acute deep vein thrombosis

The treatment of proximal deep vein thrombosis (DVT) of the lower limbs includes an initial management phase, covering the first 1 to 3 weeks, a primary treatment phase, lasting a minimum of 3 months, and a secondary treatment phase for those patients requiring continuing anticoagulation beyond the first 3 to 6 months. During the initial phase most patients with DVT can be managed as outpatients. Exclusion criteria for home treatment include high risk of bleeding, limb threatening DVT or other conditions requiring hospitalisation. Anticoagulant drugs represent the mainstay of treatment and include parenteral drugs such as unfractionated heparin or low molecular weight heparin, and oral drugs such as the vitamin K antagonists and the direct oral anticoagulants (DOACs). DOACs are currently recommended as the first line of treatment for proximal DVT of the lower limbs, with no preference for one DOAC over another. Factors to consider when choosing the anticoagulant strategy include, among others, renal and liver function, underlying diseases such as cancer or the antiphospholipid syndrome, and patient preferences. Indefinite duration of anticoagulation beyond the first 3 to 6 months is recommended for patients with unprovoked DVT and patients with permanent, chronic risk factors. Two DOACs, namely apixaban and rivaroxaban, can be administered at low doses for the secondary prevention of DVT. Elastic compression stockings (ECS) have been used for decades in patients with proximal DVT with the aim of counteracting the venous hypertension generated by the vascular disorder and reducing leg edema and to prevent the post-thrombotic syndrome.

Factor Xa Inhibitors versus warfarin in patients with morbid obesity and atrial fibrillation

PURPOSE

Factor Xa Inhibitors have emerged as a first-line agent in the management of non-valvular atrial fibrillation (NVAF), but there is a need for additional data surrounding their use in the morbidly obese population. The purpose of this study was to evaluate whether Factor Xa Inhibitors are as safe and effective as warfarin for the treatment of NVAF in individuals with a BMI ≥ 40 kg/m2 and/or weight ≥ 120 kg.

METHODS

This was a multi-center retrospective cohort study comparing the use of Factor Xa Inhibitors (apixaban and rivaroxaban) to warfarin for the management of NVAF in adult patients with a BMI ≥ 40 kg/m2 and/or weight ≥ 120 kg. The primary outcomes were stroke or systemic embolism and major bleeding within 12 months.

RESULTS

A total of 3,156 patients were included in the final analysis; 1,396 in the warfarin group and 1760 in the Factor Xa Inhibitor group. The mean weight and BMI of the overall cohort was 134.1 kg and 44.7 kg/m2, respectively. There was no difference in stroke or systemic embolism (OR 1.21, 95% CI 0.78-1.85) or major bleeding (OR 0.99, 95% CI 0.65 - 1.53) with Factor Xa Inhibitors compared to warfarin after controlling for covariates.

CONCLUSION

This analysis of real-world data suggests no difference in bleeding or thrombotic outcomes for severely obese patients with NVAF taking Factor Xa Inhibitors compared to warfarin. Overall, our study adds further data to support the use of Factor Xa Inhibitors as an alternative to warfarin in severely obese patients with NVAF.

Efficacy and Safety of Direct Oral Anticoagulants versus Warfarin in Obese Patients (BMI ≥ 30 kg/m2) with Atrial Fibrillation or Venous Thromboembolism: An Updated Systematic Review and Meta-Analysis

Background: Real-world data show limited utilization of direct oral anticoagulants (DOACs) in obese patients (body mass index [BMI] ≥ 30 kg/m2) due to concerns regarding their efficacy and safety in this demographic. Aim: This review aimed to consolidate current evidence on the efficacy and safety of DOACs versus warfarin in obese patients with non-valvular atrial fibrillation (AF) or venous thromboembolism (VTE). The primary efficacy outcome assessed a composite of all-cause mortality, stroke, systemic embolism (SE), and myocardial infarction (MI). Methods: A systematic search was conducted in MEDLINE, SCOPUS, and Cochrane databases from inception to December 28, 2023. Data were synthesized using random-effects meta-analysis. Results: A total of 35 studies involving 434,320 participants were analyzed. DOAC use was associated with a significant reduction in the risk of the composite outcome (RR = 0.80, 95% CI [0.65, 0.98], I2 = 95%), hemorrhagic stroke (RR = 0.58, 95% CI [0.38, 0.88], I2 = 92%), major bleeding (RR = 0.76, 95% CI [0.63, 0.92], I2 = 94%), gastrointestinal bleeding (RR = 0.59, 95% CI [0.49, 0.72], I2 = 88%), and intracranial bleeding (RR = 0.45, 95% CI [0.34, 0.60], I2 = 44%) compared to warfarin. A non-significant benefit of DOACs was observed for all-cause mortality, MI, the composite of stroke or SE, ischemic stroke, SE, VTE, and minor bleeding compared to warfarin. Subgroup analysis indicated no significant effect modification based on the indication for anticoagulation or study design. Conclusions: DOACs demonstrated a favorable efficacy and safety profile in obese individuals compared to warfarin.

Safety and Efficacy of Direct Oral Anticoagulants vs Warfarin in Patients With Obesity and Venous Thromboembolism: A Retrospective Analysis

BACKGROUND

Current venous thromboembolism guidelines recommend using direct oral anticoagulants (DOACs) over warfarin regardless of obesity status; however, evidence remains limited for the safety and efficacy of DOAC use in patients with obesity. This retrospective analysis sought to demonstrate the safety and efficacy of DOACs compared with warfarin in a diverse population of patients with obesity in light of current prescribing practices.

METHODS

A retrospective cohort study was conducted at a large academic health system between July 2014 and September 2019. Adults with an admission diagnosis of deep vein thrombosis (DVT) or pulmonary embolism, with weight greater than 120 kg or a body mass index greater than 40, and who were discharged on an oral anticoagulant were included. Outcomes included occurrence of a thromboembolic event (DVT, pulmonary embolism, or ischemic stroke), bleeding event requiring hospitalization, and all-cause mortality within 12 months following index admission.

RESULTS

Out of 787 patients included, 520 were in the DOAC group and 267 were in the warfarin group. Within 12 months of index hospitalization, thromboembolic events occurred in 4.23% of patients in the DOAC group vs 7.12% of patients in the warfarin group (hazard ratio, 0.6 [95% CI, 0.32-1.1]; P = .082). Bleeding events requiring hospitalization occurred in 8.85% of DOAC patients vs 10.1% of warfarin patients (hazard ratio, 0.93 [95% CI, 0.57-1.5]; P = .82). A DVT occurred in 1.7% and 4.9% of patients in the DOAC and warfarin groups, respectively (hazard ratio, 0.35 [95% CI, 0.15-0.84]; P = .046).

CONCLUSION

No significant differences could be determined between DOACs and warfarin for cumulative thromboembolic or bleeding events, pulmonary embolism, ischemic stroke, or all-cause mortality. The risk of DVT was lower with apixaban and rivaroxaban. Regardless of patient weight or body mass index, physicians prescribed DOACs more commonly than warfarin.

Safety and efficacy of direct oral anticoagulants in comparison to warfarin in obese patients with atrial fibrillation: A systematic review and meta-analysis

Background and Aim

Obesity affects nearly 650 million adults worldwide, and the prevalence is steadily rising. This condition has significant adverse effects on cardiovascular health, increasing the risk of hypertension, coronary artery disease, heart failure, and atrial fibrillation (AF). While anticoagulation for obese patients with AF is a well-established therapy for the prevention of thromboembolism, the safety and efficacy of different anticoagulants in this specific population are not well explored. This meta-analysis aimed to compare direct oral anticoagulants (DOAC) to vitamin K antagonists in obese populations with AF.

Methods

The PRISMA guidelines were followed for this meta-analysis, registered in PROSPERO (CRD42023392711). PubMed, PubMed Central, Embase, Cochrane Library, and Scopus databases were searched for relevant articles from inception through January 2023. Two independent authors screened titles and abstracts, followed by a full-text review in Covidence. Data were extracted in Microsoft Excel and analyzed using RevMan v5.4 using odds ratio as an effect measure.

Results

Two thousand two hundred fifty-nine studies were identified from the database search, and 18 were included in the analysis. There were statistically significant reductions in the odds of ischemic and hemorrhagic stroke in the DOAC group compared with the VKA group (OR 0.70, CI 0.66-0.75) and (OR 0.47, CI 0.35-0.62), respectively. In addition, the DOAC group exhibited lower odds of systemic embolism (OR 0.67, CI 0.54-0.83), major bleeding (OR 0.62, CI 0.54-0.72), and composite outcome (OR 0.72, CI 0.63-0.81).

Conclusion

Based on the findings from this meta-analysis, DOACs demonstrate superior safety and efficacy in obese patients with AF compared with VKAs. These results may have significant implications for guiding anticoagulation strategies in this patient population.

Retrospective, multicenter analysis of the safety and effectiveness of direct oral anticoagulants for the treatment of venous thromboembolism in obesity

BACKGROUND

Direct oral anticoagulants (DOACs) are the preferred treatment for venous thromboembolism (VTE). However, DOAC use in patients with a BMI greater than 40 kg/m2 has not been well studied despite the growing prevalence of obesity, and current literature is often underpowered.

METHODS

This multicenter, retrospective, observational study evaluated patients 18 years and older who received DOACs for acute VTE treatment. Patients receiving DOACs for recurrent VTE or for failure of another agent were excluded. The primary efficacy outcome was recurrent VTE and the primary safety outcome was major bleeding within 12 months (or one month after stopping anticoagulation therapy). A propensity score analysis was performed to balance patient characteristics and evaluate the primary endpoints by BMI group. Time-to-event outcomes were analyzed using weighted Kaplan-Meier curves.

RESULTS

There were 165 patients with a BMI of at least 40 kg/m2 and 320 patients with a BMI less than 40 kg/m2. The majority received apixaban (373, 77%). Recurrent VTE occurred in 5 (3.0%) and 13 (4.1%) of patients in the higher and lower BMI groups, respectively (adjusted OR: 0.66; 95% CI: 0.16-2.69). Major bleeding occurred in 5 (3.0%) and 15 (4.7%) of patients in the higher and lower BMI groups, respectively (adjusted OR: 1.19; 95% CI: 0.36-3.92).

CONCLUSION

There was no significant difference in VTE recurrence or major bleeding related to BMI among patients treated with DOACs. This study showed that DOACs may be a safe and effective VTE treatment option in patients with obesity.

Efficacy and safety of rivaroxaban versus apixaban for venous thromboembolism: A systematic review and meta-analysis of observational studies

BACKGROUND

Direct-acting oral anticoagulants (DOACs) including rivaroxaban and apixaban are preferred over vitamin K antagonists for the treatment of venous thromboembolism (VTE). We conducted a systematic review and a meta-analysis to compare the efficacy and safety of rivaroxaban versus apixaban in the treatment of VTE.

METHODS

We conducted an electronic search for studies that directly compared treatment with rivaroxaban and apixaban in adult patients with VTE. The relative risks (RRs) and 95% confidence intervals (CIs) were estimated and pooled using a fixed-effect model unless significant heterogeneity was present (I2 > 40%), then random-effects model was used. The primary efficacy and safety outcomes were recurrent VTE (rVTE) and major bleeding events, respectively.

RESULTS

Nine observational studies were included in our meta-analysis, assessing 24,156 patients for apixaban and 38,847 for rivaroxaban. Pooling of data for our primary efficacy outcome showed a trend towards lower risk of rVTE with apixaban compared to rivaroxaban (RR 0.77, 95% CI 0.57-1.04, I2 = 53%). Analysis of our primary safety outcome showed a significantly lower risk of major bleeding with apixaban compared to rivaroxaban (RR 0.68, 95% CI 0.61-0.76, I2 = 0%). Apixaban was associated with significantly decreased risk of net clinical harm, clinically relevant non major bleeding (CRNMB) and any bleeding, compared to rivaroxaban (RR 0.75, 95% CI 0.61-0.92, I2 = 50%; RR 0.58, 95% CI 0.50-0.67, I2 = 7%; RR 0.64, 95% CI 0.59-0.70, I2 = 0%, respectively).

CONCLUSIONS

Apixaban is associated with a significantly lower risk of major bleeding compared to rivaroxaban for treatment of VTE. Given the limitations of the existing evidence, further interventional studies comparing the two drugs are needed.

Comparing the Clinical Outcomes Observed with Rivaroxaban Versus Warfarin for the Management of Obese Patients with Non-valvular Atrial Fibrillation: a Systematic Review and Meta-analysis

BACKGROUND

Atrial fibrillation (AF) is an irregular heart rhythm which is becoming more and more common in this new era. Obesity is a risk factor for cardiovascular events, and obese patients are more at risk for stroke. The Framingham Heart Study demonstrated an increase in the developmental risk of AF by 4% for every unit (kg/m2) increase in body mass index (BMI). An anticoagulant is often required for the management of such patients. In this analysis, we aimed to systematically compare the clinical outcomes which were associated with rivaroxaban versus warfarin for the treatment of obese patients with non-valvular AF.

METHODS

PubMed, EMBASE, Web of Science, http://www.

CLINICALTRIALS

gov , Google Scholar, and Cochrane Central were the searched databases. Clinical outcomes including stroke, systemic embolism, and major bleeding were the endpoints. In this study, dichotomous data were analyzed by the RevMan software version 5.4. Risk ratio (RR) with 95% confidence interval (CI) was used for result interpretation.

RESULTS

Ten studies consisting of a total number of 168,081 obese participants were included whereby 81,332 participants were treated with rivaroxaban and 86,749 participants were treated with warfarin. The risks of ischemic (RR: 0.79, 95% CI: 0.74-0.84; P = 0.00001) and hemorrhagic stroke (RR: 0.61, 95% CI: 0.48-0.76; P = 0.0001) as well as systemic embolism (RR: 0.73, 95% CI: 0.62-0.87; P = 0.0004) were significantly lower with rivaroxaban compared to warfarin for the management of these obese patients with non-valvular AF. Rivaroxaban was also associated with a significantly lower risk of major bleeding (RR: 0.75, 95% CI: 0.65-0.87; P = 0.0001).

CONCLUSION

Based on this analysis, rivaroxaban seemed to be a better option in comparison to warfarin, due to its association with significantly lower risks of stroke and bleeding outcomes in obese patients with non-valvular AF. However, this hypothesis should further be confirmed in larger clinical trials.

The safety and efficacy of nonvitamin K antagonist oral anticoagulants in morbidly obese patients with atrial fibrillation: a meta-analysis

BACKGROUND AND AIM

Atrial fibrillation (AF) is the most frequently observed cardiac arrhythmia in clinical settings. Obesity can influence the efficacy of the treatment administered, which requires a larger dose and more time to accomplish therapeutic targets due to altered pathophysiology. Our study aimed to assess the overall efficacy and safety of nonvitamin K antagonist oral anticoagulants (NOACs) versus warfarin in AF patients with morbid obesity (BMI > 40 kg/m2 and/or weight > 120 kg) to prevent complications.

METHODS

We conducted a literature search on PubMed, Web of Science, the Cochrane Library, and Scopus till October 2022 for articles addressing the efficacy and safety of NOACs versus warfarin for the treatment of AF in morbidly obese patients. We performed the meta-analysis with RevMan software version 5.4 and Open Meta Analyst. The main outcomes assessed were stroke, major bleeding, and minor bleeding after anticoagulation, as did the history of comorbidities and risk factors in morbidly obese patients. Quality assessment was performed using Cochrane's ROB-2 tool and the Newcastle-Ottawa scale.

RESULTS

Regarding major bleeding events, pooled data showed that patients taking NOACs had a significantly lower risk than patients taking warfarin (OR = 0.54, 95% CI: [0.41-0.70]; p < 0.00001). However, for minor bleeding, there was a nonsignificant effect of NOACs on reducing the risk of bleeding (OR = 0.72, 95% CI = 0.47-1.09; p = 0.12), which became highly significant in favor of NOACs after sensitivity analysis (OR = 0.55, 95% CI = 0.49-0.61]; p < 0.00001). There was a significant difference in the incidence of stroke between the NOAC group and the warfarin group (OR = 0.69, 95% CI = 0.60-0.80]; p < 0.00001). According to the results of the single-arm study analysis, the overall effect of all the outcomes was associated with a high risk of disease development in patients receiving NOACs.

CONCLUSION

Our meta-analysis showed a favorable effect of NOACs vs warfarin in morbidly obese patients. Some outcomes were not significantly different, which calls for future research to better assess their safety and efficacy in this particular weight group.

TRIAL REGISTRATION

The study was registered with PROSPERO under registration number CRD42022362493 on October 2022.

Direct Oral Anticoagulants in Special Patient Populations

Anticoagulants are a cornerstone of treatment in atrial fibrillation. Nowadays, direct oral anticoagulants (DOACs) are extensively used for this condition in developed countries. However, DOAC treatment may be inappropriate in certain patient populations, such as: patients with chronic kidney disease in whom DOAC concentrations may be dangerously elevated; frail elderly patients with an increased risk of falls; patients with significant drug-drug interactions (DDI) affecting either DOAC concentration or effect; patients at the extremes of body mass in whom an "abnormal" volume of distribution may result in inappropriate drug concentrations; patients with recurrent stroke reflecting an unusually high thromboembolic tendency; and, lastly, patients who experience major hemorrhage on an anticoagulant and in whom continued anticoagulation is deemed necessary. Herein we provide a fictional case-based approach to review the recommendations for the use of DOACs in these special patient populations.

Use of direct oral anticoagulants for venous thromboembolism treatment at extremes of body weight, renal and liver function: an illustrated review

Direct oral anticoagulants (DOACs) have been a welcome addition to clinical practice due to the practical advantages they confer over traditional anticoagulants. In many countries, DOACs are now used as first-line treatment for the management of venous thromboembolism (VTE). Traditional anticoagulants allow for a degree of individualization, either through monitoring the international normalized ratio in the case of vitamin-K antagonists or through dose titration according to bodyweight in the case of low-molecular-weight heparin. However, the use of fixed doses and removal of the need for routine monitoring has created uncertainty in prescribing DOACs for patients at the extremes of bodyweight, renal function, and patients with liver impairment, who were not well represented in the DOAC licensing clinical trials. The discipline of pharmacokinetics is concerned with the movement of drugs through the body. Although the extremes of bodyweight and renal and liver function will influence the pharmacokinetics of DOACs, are these changes significant enough to affect clinical outcomes of bleeding and thrombosis? In other words, can the fixed-dosing strategy of DOACs accommodate these differences in physiology? In this review, we recap key pharmacokinetic principles for drug dosing; review venous thromboembolism trial and real-world data on patients prescribed DOACs at the extremes of bodyweight, renal function, and liver function; relate this to the pharmacokinetic properties of DOACs; and summarize the state of the field and current unknowns.

A Real-World Comparison of Apixaban and Rivaroxaban in Obese and Morbidly Obese Patients With Nonvalvular Atrial Fibrillation

Background: Contemporary guidelines for managing nonvalvular atrial fibrillation (NVAF) include apixaban and rivaroxaban as first-line anticoagulation treatment options. Minimal guidance is available regarding selecting anticoagulants for patients with class I-III obesity. Objective: This study aims to evaluate the comparative effectiveness and safety of apixaban and rivaroxaban in both obese and morbidly obese patients with NVAF. Methods: A retrospective cohort study was conducted at an outpatient cardiovascular clinic after Institutional Review Board approval. Patients were eligible if they were ≥18 years of age, had a BMI ≥30 kg/m2, and took apixaban or rivaroxaban for NVAF for ≥3 months. The primary endpoint was the composite rate of stroke, transient ischemic attack (TIA), myocardial infarction (MI), or presence of atrial thrombosis. Bleeding events were evaluated as the primary safety endpoint. Results: Combined, the cohorts consisted of 303 obese or morbidly obese patients. The primary composite endpoint occurred in 3.8% of patients taking apixaban and 1.7% of patients taking rivaroxaban (P = .28). Both clinically relevant, non-major and major bleeding occurred more often in the apixaban arm, but this difference was not statistically significant; however, bleeding risk may have been skewed due to differences in baseline characteristics. Conclusion and Relevance: For obese and morbidly obese patients prescribed either apixaban or rivaroxaban for NVAF, rates of stroke, TIA, MI, and atrial thrombosis did not differ. The preferred DOAC for patients with class I-III obesity remains elusive, but current data points to a patient-centered approach for anticoagulant selection.

Effectiveness and safety of non-vitamin K antagonist oral anticoagulant in the treatment of patients with morbid obesity or high body weight with venous thromboembolism: A meta-analysis

BACKGROUND

Venous thromboembolism (VTE) poses a significant health risk to patients with morbid obesity or high body weight. Non-vitamin K antagonist oral anticoagulants (NOACs) are emerging treatments, but their effectiveness and safety compared with vitamin K antagonists (VKAs) in this population are yet to be thoroughly studied.

METHODS

We conducted a systematic review and meta-analysis, adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Four electronic databases were searched for relevant studies comparing the efficacy and safety of NOACs and VKAs in treating patients with VTE with a body mass index > 40 kg/m2 or body weight > 120 kg. Eligible studies were scored for quality using the Newcastle-Ottawa Scale.

RESULTS

Thirteen studies were included. The meta-analysis results showed that compared to VKAs, NOACs significantly decreased the risk of VTE occurrence (odds ratio = 0.72, 95% CI: 0.57-0.91, I2 = 0%, P < .001) and were associated with a lower risk of bleeding (odds ratio = 0.74, 95% CI: 0.58-0.95, I2 = 0%, P < .05). Subgroup analysis showed that in the cancer patient subgroup, both risks of VTE occurrence and bleeding were lower in the NOAC group than in the VKA group. In patients without cancer, the risk of VTE was significantly lower in the NOAC group.

CONCLUSION

NOACs appear to be more effective and safer than VKAs in patients with morbid obesity or a high body weight with VTE. However, further large-scale randomized controlled trials are required to confirm these findings.

XGBoost-based machine learning test improves the accuracy of hemorrhage prediction among geriatric patients with long-term administration of rivaroxaban

BACKGROUND

Hemorrhage is a potential and serious adverse drug reaction, especially for geriatric patients with long-term administration of rivaroxaban. It is essential to establish an effective model for predicting bleeding events, which could improve the safety of rivaroxaban use in clinical practice.

METHODS

The hemorrhage information of 798 geriatric patients (over the age of 70 years) who needed long-term administration of rivaroxaban for anticoagulation therapy was constantly tracked and recorded through a well-established clinical follow-up system. Relying on the 27 collected clinical indicators of these patients, conventional logistic regression analysis, random forest and XGBoost-based machine learning approaches were applied to analyze the hemorrhagic risk factors and establish the corresponding prediction models. Furthermore, the performance of the models was tested and compared by the area under curve (AUC) of the receiver operating characteristic (ROC) curve.

RESULTS

A total of 112 patients (14.0%) had bleeding adverse events after treatment with rivaroxaban for more than 3 months. Among them, 96 patients had gastrointestinal and intracranial hemorrhage during treatment, which accounted for 83.18% of the total hemorrhagic events. The logistic regression, random forest and XGBoost models were established with AUCs of 0.679, 0.672 and 0.776, respectively. The XGBoost model showed the best predictive performance in terms of discrimination, accuracy and calibration among all the models.

CONCLUSION

An XGBoost-based model with good discrimination and accuracy was built to predict the hemorrhage risk of rivaroxaban, which will facilitate individualized treatment for geriatric patients.

The Effectiveness and Safety of Direct Oral Anticoagulants in Obese Patients With Atrial Fibrillation: A Network Meta-Analysis

Atrial fibrillation (AF) is a cardiac condition characterized by an irregular heart rhythm, which is increasingly prevalent in the modern era. All international guidelines strongly advise the administration of anticoagulants to individuals with AF who are at high risk of stroke. These guidelines recommend the use of direct oral anticoagulants (DOACs) over warfarin because warfarin is significantly associated with increased rates of major bleeding, numerous interactions with food and drugs, and the necessity for frequent monitoring. The aim of this study is to compare the effectiveness and safety of direct oral anticoagulants (DOACs) in obese patients with atrial fibrillation. Two authors independently conducted a comprehensive literature search using electronic databases including PubMed, CINAHL, and EMBASE from inception to June 1, 2023. The efficacy outcome assessed in this meta-analysis included the composite of stroke and systemic embolism. For safety analysis, major bleeding events were compared among the study groups. Eleven studies fulfilled all the inclusion criteria and were included in the present meta-analysis enrolling 144,502 patients. In this study, DOACs demonstrate superior efficacy in preventing stroke/systemic embolism compared to warfarin. Among the DOACs, apixaban emerged as the most effective, followed by rivaroxaban, warfarin, and dabigatran. In terms of safety, apixaban was also found to be the most favorable treatment option, followed by rivaroxaban, dabigatran, and warfarin. In summary, our study concludes that apixaban exhibited greater effectiveness and safety when compared to other DOACs and warfarin in obese patients with AF.

Novel Isosteviol-Based FXa Inhibitors: Molecular Modeling, In Silico Design and Docking Simulation

Direct oral anticoagulants are an important and relatively new class of synthetic anticoagulant drugs commonly used for the pharmacotherapy of thromboembolic disorders. However, they still have some limitations and serious side effects, which continuously encourage medicinal chemists to search for new active compounds acting as human-activated coagulation factor X (FXa) inhibitors. Isosteviol is a nontoxic hydrolysis product of naturally occurring stevioside and possesses a wide range of therapeutic properties, including anticoagulant activity. The present contribution describes the in silico design of novel oxime ether isosteviol derivatives as well as a molecular modeling approach based on QSAR analysis and a docking simulation for searching for novel isosteviol-based compounds as potential FXa inhibitors. The elaborated ANN model, encompassing topological and geometrical information, exhibited a significant correlation with FXa-inhibitory activity. Moreover, the docking simulation indicated six of the most promising isosteviol-like compounds for further investigation. Analysis showed that the most promising derivatives contain heterocyclic, aromatic, five-membered moieties, with substituents containing chlorine or fluorine atoms. It is anticipated that the findings reported in the present work may provide useful information for designing effective FXa inhibitors as anticoagulant agents.

DOAC compared with warfarin for VTE in patients with obesity: a retrospective cohort study conducted through the VENUS network

The effectiveness and safety of direct oral anticoagulants (DOAC) compared with warfarin remains uncertain in obese patients. We assessed the comparative effectiveness and safety of DOACs with warfarin for the treatment of VTE among obese patients. This multi-center retrospective cohort study included adults with a BMI ≥ 35 kg/m2 or weight ≥ 120 kg prescribed either DOAC (apixaban, dabigatran, edoxaban, rivaroxaban) or warfarin for a VTE diagnosis. The primary outcome was the 12-month rate of recurrent VTE. The secondary outcome was the 12-month rate of major bleeding. Among 5626 patients, 67% were prescribed warfarin and 33% were prescribed a DOAC. The 12-month VTE recurrence rate was 3.6% (67/1823) for patients treated with DOAC compared with 3.8% (143/3664) for patients treated with warfarin [odds ratio for recurrent VTE on warfarin versus DOAC (OR) (95% CI).07 (0.80, 1.45)]. The 12-month major bleeding rate was 0.5% (10/1868) for patients on DOAC versus 2.4% (89/3758) on warfarin [OR 4.25 (2.19, 8.22)]. Similar proportions of recurrent VTE occurred across BMI thresholds on DOAC and warfarin: for BMI ≥ 35 kg/m2 (N = 5412), 3.6% versus 3.8%, respectively [OR 1.08 (0.80, 1.46)]; for BMI ≥ 40 kg/m2 (N = 2321), 4.4% versus 3.5%, respectively [OR 0.80 (0.51, 1.26)]; and for BMI ≥ 50 kg/m2 (N = 560), 3.1% versus 3.7%, respectively [OR 1.18 (0.39, 3.56)]. Similar proportions of recurrent VTE occurred in patients with obesity treated for VTE with DOACs and warfarin. DOACs were associated with lower major bleeding compared to warfarin in patients with obesity and VTE.

Apixaban for treatment of venous thromboembolism in an obese patient with Glanzmann thrombasthenia

Background

Glanzmann thrombasthenia (GT) is a rare congenital platelet function disorder associated with a severe bleeding diathesis. Thrombotic manifestations remain a rare condition. We report here the first case of recurrent venous thromboembolism (VTE) successfully treated with apixaban in a patient with GT. Our patient's morbid obesity was an additional challenge.

Key Clinical Question

The Key Clinical Question was to determine if direct oral anticoagulants are suitable for patients with both obesity and GT.

Clinical Approach

In our patient, the first episode of VTE occurred after the use of a low dose of activated recombinant factor VII for a minor procedure, whereas the second was unprovoked. Administration of rivaroxaban very quickly led to the appearance of bleeding symptoms and subsequently led to poor compliance and extension of deep vein thrombosis. The patient was switched to apixaban, with very good efficacy and safety over the cumulative 18 months of use.

Conclusion

The last updated guidelines now recommend the use of rivaroxaban and apixaban for management of VTE in patients with obesity. Regarding patients with GT, there is still insufficient data on the use of direct oral anticoagulants. Management of thrombotic manifestations in these patients remains a rare and complex condition and could be improved by the creation of a specific international registry.

Pharmacist Practice Patterns Regarding Direct Oral Anticoagulants for Treatment of Venous Thromboembolism

Background: Direct oral anticoagulants (DOACs) are increasingly prescribed for the treatment of venous thromboembolism (VTE). However, little is known regarding pharmacists' practice patterns and preferences in clinical areas of contention, such as initiation dosing, obesity, and renal impairment. Objective: To determine pharmacist trends in practice regarding DOACs for the treatment of VTE overall and within areas of clinical controversy. Methods: An electronic survey was distributed to pharmacists in the United States through national and state pharmacy organizations. Responses were collected for 30 days. Results: One hundred fifty-three complete responses were submitted. The majority of pharmacists preferred apixaban (90.2%) for the oral treatment of venous thromboembolism. When initiating apixaban or rivaroxaban for a new VTE, 76% and 64% of pharmacists surveyed, respectively, state the duration of the initiation dose phases are reduced if the patient received parenteral anticoagulation. Fifty-eight percent of pharmacists used body mass index to evaluate the appropriateness of DOACs in obese patients whereas 42% used total body weight. Preference for rivaroxaban (31.4%) was higher in this population compared to the global population (10%). Apixaban was preferred for patients with renal impairment (92.2%). However, as creatinine clearance as calculated by the Cockcroft-Gault equation (CrCl) reduced to ≤15 milliliters/minute (mL/min), preference for warfarin increased (36%). Conclusion: This national survey of pharmacists demonstrated an overall preference for apixaban and significant variability in practice patterns regarding DOACs for patients with new VTE, patients with obesity, and patients with renal impairment. Further research is warranted to evaluate the efficacy and safety of DOAC initiation dosing phase modifications. Prospective evaluations of DOACs in obese and renal dysfunction populations would confirm the safety and efficacy of DOACs in these populations.

Factor Xa inhibitors versus vitamin K antagonist in morbidly obese patients with venous thromboembolism: a systematic review and meta-analysis

INTRODUCTION

Guidelines have endorsed non-vitamin K antagonist oral anticoagulants (NOACs), consisting of factor Xa inhibitors (xabans) and direct thrombin inhibitors, as the first line of treatment in venous thromboembolism (VTE) and atrial fibrillation. However, morbidly obese patients were under-represented in landmark trials of NOACs. Therefore, this study aimed to systematically review and perform a meta-analysis of studies on xabans versus vitamin K antagonist (VKA) in this high-risk population with VTE.

METHODS

PubMed, Embase, Medline, Cochrane library, and Google Scholar databases were searched to identify studies that compared xabans and VKA in treating morbidly obese patients with VTE. Morbid obesity was defined as body weight ≥ 120 kg or BMI ≥ 40 kg/m². Outcomes of interest included recurrent VTE, major bleeding, and clinically relevant non-major bleeding (CRNMB).

RESULTS

Eight studies comprising 30,895 patients were included. A total of 12,755 patients received xabans while 18,140 received VKAs. No significant difference in the odds of recurrent VTE (OR 0.75, 95% CI 0.55-1.01) and CRNMB (OR 0.69, 95% CI 0.44-1.09) was observed between the xabans group and the VKA group. However, the xabans group was associated with lower odds of major bleeding (OR 0.70, 95% CI 0.59-0.83).

CONCLUSION

Xabans have lower odds of major bleeding but similar odds of recurrent VTE when compared with VKAs in treating VTE in morbidly obese patients. Large registry analyses or future randomized controlled trials will be helpful in confirming these findings.

Direct Oral Anticoagulants in Obese Patients with Venous Thromboembolism: Results of an Expert Consensus Panel

In clinical practice, direct oral anticoagulants (DOACs) are increasingly used for venous thromboembolism treatment and prevention. A substantial proportion of patients with venous thromboembolism are also obese. International guidance published in 2016 stated that DOACs could be used in standard doses in patients with obesity up to a body mass index [BMI] of 40 kg/m², but should not be used in those with severe obesity (BMI > 40 kg/m²) owing to limited supporting data at the time. Although updated guidance in 2021 removed this limitation, some healthcare providers still avoid DOACs even in patients with lower levels of obesity. Furthermore, there are still evidence gaps regarding treatment of severe obesity, the role of peak and trough DOAC levels in these patients, use of DOACs after bariatric surgery, and appropriateness of DOAC dose reduction in the setting of secondary venous thromboembolism prevention. This document describes proceedings and outcomes of a multidisciplinary panel convened to review these and other key issues regarding DOAC use for treatment or prevention of venous thromboembolism in individuals with obesity.

Pharmacokinetics and Dosing Regimens of Direct Oral Anticoagulants in Morbidly Obese Patients: An Updated Literature Review

Data on the impact of morbid obesity (body mass index [BMI] ≥ 40 kg/m²) on the pharmacokinetics (PK), pharmacodynamics (PD) of direct oral anticoagulants (DOACs) are relatively limited, making it difficult to design optimal dosing regimens in morbidly obese patients.To review literature on PK/PD profile, efficacy, and safety of DOACs in venous thromboembolism (VTE) and nonvalvular atrial fibrillation (AF) patients with morbid obesity and make recommendations regarding optimal dosing regimens in these patient populations.A detailed literature search was conducted (from inception to June 22, 2022) for relevant articles involving PK/PD and clinical data on DOACs use in morbidly obese patients with VTE or AF, or healthy volunteers.A total of 28 studies were identified. DOAC-specific PK variations and clinical outcomes have been observed. Obesity may have a modest effect on PK/PD of dabigatran, apixaban, or rivaroxaban. Dabigatran was effective in AF patients with morbid obesity but might increase the risk of gastrointestinal bleeding. Standard dosing of apixaban or rivaroxaban is effective and safe for VTE and AF patients with morbid obesity. Trough edoxaban concentration and anti-Xa activity were similar in different BMI groups (18.5 to >40 kg/m²), and standard dosing of edoxaban may be effective and safe for AF patients.Current evidence suggests dabigatran should be used with caution in patients with AF as it might increase the risk of gastrointestinal bleeding; Standard dosing of apixaban or rivaroxaban can be used in VTE or AF patients; Standard dosing of edoxaban may be considered in AF patients.

Warfarin Time in Therapeutic INR Range and Direct Oral Anticoagulant Adherence for Venous Thromboembolism Across the Spectrum of Weight and Body Mass Index: Findings from Veterans Health Administration

The evidence of direct oral anticoagulants (DOACs) usage for venous thromboembolism (VTE) in patients at extremes of body weight or mass index is limited. In such situations, warfarin may be more frequently used. We investigated warfarin time in the therapeutic international normalized ratio range (TTR) and DOAC adherence based on the calculated proportion of days covered (PDC) by pill coverage from a DOAC prescription in patients with VTE across all body sizes. Using data from the Veterans Health Administration (VA), we identified first-time patients with VTE between 2013 and 2018 treated with warfarin or DOACs. We analyzed 28,245 patients with warfarin TTR (N  =  10,167) or DOAC PDC(N  =  18,078). For warfarin-treated patients after index VTE, mean TTR was lower over shorter treatment durations (TTR 30 vs TTR 180 [mean  ±  SD]: 43.8% ± 33.5% vs 58.8% ± 23.5%). Mean TTR over 180 days after VTE was lowest for patients <60 kg (TTR 180 [mean  ±  SD]: <60kg: 49.3% ± 24.2% vs ≥60 to <100 kg: 57.8% ± 23.4%; P < .0001). For DOAC-treated patients over 180 days after index VTE, mean PDC was lowest for patients <60 kg (PDC 180 [mean  ±  SD]: < 60kg: 76.9% ± 33.2% vs ≥ 60 to <100 kg: 83.6% ± 27.7%; P < .0001).Most DOAC-treated patients attained sufficient adherence across the body size spectrum while warfarin-treated patients <60kg were at risk for low TTR.

Safety and efficacy of apixaban, dabigatran and rivaroxaban in obese and morbidly obese patients with heart failure and atrial fibrillation: A real-world analysis

BACKGROUND

Atrial fibrillation and heart failure are combined risk factors for thromboembolic events. Obese and morbidly obese individuals have been underrepresented in clinical trials studying safety and efficacy of direct oral anticoagulants (DOACs).

OBJECTIVES

Study the comparative safety and efficacy of DOACs in obese and morbidly obese patients with atrial fibrillation or flutter, and concomitant congestive heart failure.

METHODS

In the present single-center retrospective observational study, patients with an ICD-9 code of atrial fibrillation or atrial flutter, and congestive heart failure on a DOAC (apixaban[n = 155], rivaroxaban[n = 335], dabigatran[n = 393]) were followed for a median 12.5 months (IQR: 22.1 months). Obesity was defined as a body mass index, BMI ≥ 30 and < 40 kg/m² [n = 614], and morbid obesity as BMI ≥ 40 kg/m² [n = 269]. Clinical endpoints were grouped into safety (composite of intracranial-hemorrhage, gastrointestinal-bleeds, hemorrhagic-stroke, and other bleeds), and efficacy (composite of ischemic-stroke and systemic-embolism) endpoints. Cox proportional hazard models were used to compare safety, efficacy, and all-cause mortality outcomes.

RESULTS

In obese patients, no statistical difference was observed in efficacy of DOACs. A statistical difference was observed in the safety of DOACs in obese patients. Apixaban was found to be safer than dabigatran [hazard ratio [HR] 0.37 (0.16-0.87), p = .02] and rivaroxaban [HR 0.29 (0.12-0.67), p = .004]. In morbidly obese patients, there was no overall statistical difference in the efficacy or safety of DOACs.

CONCLUSION

In obese patients with congestive heart failure and atrial fibrillation or atrial flutter on DOACs, apixaban has the most favorable safety profile compared to rivaroxaban and dabigatran.

Comparing the Efficacy and Safety of Apixaban Versus Warfarin in Morbidly Obese Patients

This study was conducted to evaluate the efficacy and safety of apixaban versus warfarin in morbidly obese patients. A total of 250 morbidly obese patients with a body mass index (BMI) higher than 40 kg/m² or a body weight higher than 120 kg who were on anticoagulation therapy with either apixaban or warfarin for over one month were included in the study. This retrospective cohort, multicenter study was executed using the medical records of 125 morbidly obese patients treated with apixaban, while patients on warfarin were selected using a systemic random sampling to match the sample size of the apixaban group. There was no significant difference between apixaban and warfarin in the development of thromboembolic events and major bleeding. However, incidences of minor bleeding significantly decreased in the apixaban group compared to patients treated with warfarin. This difference was overcome by controlling serum creatinine and nonsteroidal anti-inflammatory drugs (NSAIDs). In conclusion, apixaban efficacy and safety are nearly the same as that of warfarin in morbidly obese patients with a lower incidence of minor bleeding with apixaban. Controlling serum creatinine and NSAIDs use may improve warfarin safety and decrease its complications.

Anticoagulation and BMI: effect of high body weight on the safety and efficacy of direct oral anticoagulants

Obesity is an epidemic with rising prevalence, and obese patients are predisposed to comorbid conditions that increase risk for thromboembolic events. It is critical to identify safe and effective anticoagulation therapy for use in this population. Direct oral anticoagulants (DOACs) are a preferred option for anticoagulation in patients of normal weight due to many benefits and equivalent safety and efficacy to their vitamin K antagonist counterparts. However, the safety and efficacy of DOACs in obese patients is not well understood. This review describes recent studies on the pharmacokinetics, safety and efficacy, and clinical outcomes of the DOACs apixaban, rivaroxaban, edoxaban and dabigatran in obese patient populations. DOACs may be a beneficial alternative to vitamin K antagonist therapy in obese patient populations.

Evaluation of safety and efficacy outcomes of direct oral anticoagulants versus warfarin in normal and extreme body weights for the treatment of atrial fibrillation or venous thromboembolism

Despite evolving evidence, the use of direct oral anticoagulants (DOACs) in patients with extremes of body weight remains controversial. This study aimed to measure the impact of DOACs compared to warfarin on safety and efficacy outcomes in extreme body weight patients. This multi-center, health system, retrospective study examined the outcomes of patients with all body weights and extreme body weights prescribed a DOAC (rivaroxaban, apixaban, dabigatran, edoxaban) or warfarin for atrial fibrillation or venous thromboembolism over a 9-year period. The primary outcome was a composite of thromboembolism, symptomatic recurrent VTE, or severe bleeding; analyzed by pre-determined BMI cutoffs. A total of 19,697 patients were included in the study: 11,604 in the DOAC group and in the 8093 in the warfarin group. 295 patients were underweight and 9108 patients were pre-obese to obese class 3. After adjusting for potential confounders, warfarin patients had higher odds of experiencing the composite outcome compared to DOAC patients (OR 1.337, 95% CI 1.212-1.475). Additionally, obese patients were 24.6% more likely to experience the outcome compared to normal BMI patients. Adjusted modeling showed that warfarin patients experienced higher bleed rates compared to DOAC patients (OR 1.432, 95% CI 1.266-1.620). Obese patients were less likely to be diagnosed with a bleed (OR 0.749, 95% CI 0.658-0.854), and underweight patients were more likely to be diagnosed with a bleed (OR 1.522, 95% CI 1.095-2.115) compared to normal BMI patients. In conclusion, DOACs for atrial fibrillation or VTE in patients with extreme body weights appear safe and effective when compared to warfarin.

Clinical insights into management options for recurrent type 2 diabetes and cardiovascular risk after metabolic-bariatric surgery

AIMS

Long-term clinical trials evaluating the effects of metabolic-bariatric surgery (MBS) on type 2 diabetes (T2D) demonstrate that a significant proportion of patients either fail to achieve remission or experience T2D recurrence over time. Furthermore, patients with recurrent T2D might require reinstitution of pharmacotherapy to control comorbidities (hypertension, dyslipidemia). This paper reviews therapeutic options in patients with T2D relapse.

DATA SYNTHESIS

Although presently there is no recommended pharmacological strategy, the available data support GLP-1 analogues (GLP-1a) as the most suitable option to control hyperglycemia post-MBS. Beside their efficacy in lowering glycemia and body weight while preserving lean mass, GLP-1a exert cardiovascular/renal-protection and are also safe and well tolerated in surgical patients. In addition, the s.c. route of administration of these medications circumvents the problem of changes in oral drugs bioavailability following MBS. Of note, the available data refers to liraglutide and needs to be confirmed with weekly GLP-1a agents. Information regarding the impact of MBS on the pharmacokinetics of lipid lowering and anti-hypertensive drugs is scarce and inconclusive. The findings indicate that timing from intervention is particularly important because of adaptive intestinal mechanisms.

CONCLUSIONS

The recurrence of T2D following MBS is a clinically relevant issue. GLP-1a therapy represents the best option to improve glycemic and weight control with good tolerability. Long-term clinical trials will clarify the impact of these drugs on cardiovascular outcomes. A close monitoring of MBS patients is advised to guide drug dosage adjustments and ensure the control of cardiovascular risk factors.

Apixaban Use in Obese Patients: A Review of the Pharmacokinetic, Interventional, and Observational Study Data

Abstract

Relatively little is known about the influence of extreme body weight on the pharmacokinetics (PK), pharmacodynamics (PD), efficacy, and safety of drugs used in many disease states. While direct oral anticoagulants (DOACs) have an advantage over warfarin in that they do not require routine drug monitoring, some may regard this convenience as less compelling in obese patients. Some consensus guidelines discourage using DOACs in patients weighing > 120 kg or with a body mass index > 35–40 kg/m², given a sparsity of available data in this population and the concern that fixed dosing in obese patients might lead to decreased drug exposure and lower efficacy. Per the prescribing information, apixaban does not require dose adjustment in patients weighing above a certain threshold (e.g., ≥ 120 kg). Data from healthy volunteers and patients with nonvalvular atrial fibrillation (NVAF) or venous thromboembolism (VTE) have shown that increased body weight has a modest effect on apixaban’s PK. However, the paucity of exposure data in individuals > 120 kg and the lack of guideline consensus on DOAC use in obese patients continue to raise concerns about potential decreased drug exposure at extreme weight. This article is the first to comprehensively review the available PK data in obese individuals without NVAF or VTE, and PK, PD, efficacy, effectiveness, and safety data for apixaban in obese patients with either NVAF or VTE, including subgroup analyses across randomized controlled trials and observational (real-world) studies. These data suggest that obesity does not substantially influence the efficacy, effectiveness, or safety of apixaban in these patients.

Trial Registration ARISTOTLE: NCT00412984; AVERROES: NCT00496769; AMPLIFY: NCT00643201; AMPLIFY-EXT: NCT00633893; ADVANCE-1: NCT00371683; ADVANCE-2: NCT00452530; ADVANCE-3: NCT00423319

Video abstract

Effectiveness, safety, and healthcare costs associated with rivaroxaban versus warfarin among venous thromboembolism patients with obesity: a real-world study in the United States

Prior observational studies suggest rivaroxaban is safe and effective among patients with morbid obesity who suffered a venous thromboembolism (VTE) event, but existing data are more limited in the broader population of VTE patients with obesity. This study assessed VTE recurrence, major bleeding, healthcare resource utilization, and healthcare costs among VTE patients with obesity who received rivaroxaban versus warfarin. VTE patients with obesity who initiated rivaroxaban or warfarin after a first VTE (index date) were identified from the IQVIA PharMetrics® Plus database (01/02/2011–09/30/2019). The follow-up period spanned from the index date until health plan disenrollment, end of data availability, cancer diagnosis/treatment, end of the 12 month post-index period, or (for the analysis of major bleeding) anticoagulant discontinuation or switch. Patient characteristics were balanced using inverse probability of treatment weighting. The weighted rivaroxaban (N = 8666) and warfarin cohorts (N = 5946) were well balanced (mean age = 51 years, females = 52%). Over a 9.6 months mean observation period, rivaroxaban users had a significantly lower risk of VTE recurrence [7.0% vs. 8.2%, HR(95% CI) = 0.85(0.75;0.97)] and a similar risk of major bleeding [4.1% vs. 3.6%, HR(95% CI) = 1.11(0.89;1.37)] relative to warfarin users at 12 months. Relative to warfarin users, rivaroxaban users had significantly fewer all-cause outpatient visits [RR(95% CI) = 0.71(0.70;0.74)]. The higher pharmacy costs incurred by rivaroxaban recipients (cost difference = $1252) were offset by lower medical costs (cost difference = − $2515, all p < 0.05) compared with warfarin recipients. Our findings suggest that rivaroxaban is safe and effective versus warfarin, and associated with lower medical costs among VTE patients with obesity.

Management of Venous Thromboembolism in Morbid Obesity With Rivaroxaban or Warfarin

BACKGROUND

Rivaroxaban is a first-line option for the management of venous thromboembolism (VTE). However, limited data are available regarding its effectiveness in morbidly obese patients.

OBJECTIVE

To evaluate rates of thrombosis and bleeding in morbidly obese patients receiving rivaroxaban or warfarin for VTE.

METHODS

A multicenter, retrospective cohort study was conducted to compare rates of bleeding and thrombosis in patients receiving rivaroxaban versus warfarin for acute VTE. Patients were included if they were older than 18 years and had a body mass index (BMI) greater than 40 kg/m² or weight greater than 120 kg. The primary effectiveness outcome was hazard of VTE recurrence; the primary safety outcome was hazard of major bleeding. Patients were followed for up to 12 months.

RESULTS

A total of 1281 patients were identified for acute VTE and were included in this study with 487 patients receiving rivaroxaban and 785 receiving warfarin. The average cohort age was 57.6 ± 14.6 years, and the average weight was 136.4 ± 27.2 kg. After controlling for confounding factors, the use of rivaroxaban was not associated with an increased hazard of VTE events when compared with warfarin (hazard ratio [HR] = 0.69, 95% confidence interval [CI]: 0.42-1.08, P = 0.12) or major bleeding (HR = 1.29, 95% CI: 0.66-2.30, P = 0.52).

CONCLUSION AND RELEVANCE

No difference was observed in obese patients with weight >120 kg or BMI >40 kg/m² receiving rivaroxaban or warfarin for VTE treatment in hazard of VTE or major bleeding. Either agent may be considered an appropriate treatment option in this population.

Evaluation of Apixaban safety and effectiveness in morbidly obese patients with atrial fibrillation: a retrospective cohort study

Background

The benefit of apixaban to reduce stroke risk in morbidly obese patients with nonvalvular atrial fibrillation (AF) is still undetermined. The International Society of Thrombosis and Hemostasis recommends avoiding the use of direct oral anticoagulants (DOAC)s in morbidly obese patients (body mass index > 40 or weight > 120 kg) because of limited clinical data. This exploratory study aims to evaluate the effectiveness and safety of using apixaban in morbidly obese (body mass index (BMI) ≥ 40) patients with AF.

Methods

An exploratory retrospective cohort study was conducted at a single-center, including adult patients with non-valvular AF using apixaban between 01/01/2016 and 31/12/2019. Patients were excluded if they were known to have liver cirrhosis Child-Pugh C, mechanical valve, serum creatinine > 1.5 mg/dL, follow up < 3 months, or using apixaban with a dose of ≤5 or > 10 mg/day. Included patients were categorized into two groups based on their BMI (BMI<40 Vs. BMI ≥ 40). The primary outcome was all thrombotic events, while the secondary outcomes were major and minor bleeding after apixaban initiation. Propensity score (PS) matching was used (1:1 ratio) based on the patient’s age, gender, and HAS-BLED score.

Results

A total of 722 patients were eligible; 254 patients were included after propensity score matching based on the selected criteria. The prevalence of all thrombotic events was similar between the two groups in the first year of apixaban initiation (OR (95%CI): 0.58 (0.13, 2.5), p-value = 0.46). In addition, the odds of developing major and minor bleeding were not statistically significant between the two groups (OR (95%CI): 0.39 (0.07, 2.03), p-value = 0.26 and OR (95%CI): 1.27 (0.56, 2.84), p-value = 0.40), respectively).

Conclusion

This exploratory study showed similar effectiveness and safety of apixaban use in both morbid and non-morbid obese patients with non-valvular AF. However, a larger randomized controlled trial with a longer follow-up period needs to confirm our findings.

Comparing direct oral anticoagulants and vitamin K antagonist use in morbidly obese patients with venous thromboembolism: A single center retrospective cohort study

Introduction: Limited data exists on the safety and efficacy of direct‐acting oral anticoagulants (DOAC) use in morbidly obese patients with venous thromboembolism (VTE). Given the benefits of DOAC use over vitamin K antagonists (VKAs), in terms of monitoring requirements, and dietary and drug interactions, it is important to evaluate whether this is consistent in the higher risk for VTE recurrence morbidly obese group body mass index (BMI ≥ 40 kg/m²).

Materials and methods: This retrospective, single‐center cohort study included patients with a BMI of at least 40 kg/m² who were admitted to Emory University Hospital from 1^st January 2012 to 31^st May 2020 with acute VTE, and subsequently initiated on anticoagulation treatment with either DOAC or VKA (warfarin). Univariate and bivariate analyses were used to evaluate differences in demographics by treatment type and BMI. Multivariate Cox proportional hazard regression was used to assess the risk of VTE recurrence by type of treatment among morbidly obese patient subgroup.

Results: There were 247 (11.8%) morbidly obese (≥ 40 kg/m²) patients who were more likely than non‐obese patients to be younger, female, and of non‐white race. Thirty percent of the study population (n=74) had a BMI >50 kg/m². T ime‐to‐event analysis confirmed that the hazard of experiencing a recurrent thrombosis was not statistically significantly different among morbidly obese patients treated with a DOAC compared with VKA (hazard ratio [HR]: 0.28, confidence interval [CI] 0.07‐1.11, p = 0.07).

Conclusions: This study aligns with previous literature and confirms that morbidly obese patients receiving DOAC or VKA have similar risks of recurrent VTE.

Observed Apixaban Anti-Xa Levels in Obese Patients

BACKGROUND

Recent guidelines suggest that, for venous thromboembolism (VTE), standard doses of apixaban are appropriate in patients with body mass index (BMI) >40 kg/m2 or >120 kg. Atrial fibrillation (AF) is excluded from this recommendation.

OBJECTIVE

The goals of our study were to measure and describe anti-Xa levels of patients with a BMI ≥40 kg/m2 and/or a weight ≥120 kg with a clinical indication of AF or VTE who were treated with apixaban, and to determine whether BMI or weight are associated with anti-Xa levels in this population.

METHODS

We conducted an observational cohort study at a single health care system in Oregon, USA. Patients meeting enrollment criteria were recruited and had peak and trough apixaban anti-Xa levels drawn.

RESULTS

Of 55 patients enrolled, 5 (9%) had peak anti-Xa levels below the reference range and 3 (6%) had trough anti-Xa levels below the reference range. BMI did not significantly correlate with peak or trough anti-Xa levels (r = -0.10, p = 0.45 and r = -0.14, p = 0.31). Weight had a moderate, negative correlation with peak anti-Xa levels (r = -0.42, p = 0.002) and a weak, negative correlation with trough anti-Xa levels (r = -0.32, p = 0.02).

CONCLUSIONS AND RELEVANCE

This study provides evidence that anti-Xa levels among obese patients are not substantially different from patients with nomral BMI and weight. This supports recent ISTH guidance for standard dosing of apixaban for VTE patients with BMI >40 kg/m2 or weight >120 kg and provides additional evidence that the standard dosing may also be appropriate in patients with AF.

Effectiveness and Safety of Rivaroxaban versus Warfarin Among Nonvalvular Atrial Fibrillation Patients with Obesity and Polypharmacy

Background

Current evidence suggests that rivaroxaban may be well tolerated and effective in patients with nonvalvular atrial fibrillation (NVAF) and obesity; however, there is limited evidence on the impact of polypharmacy in this population. This study evaluated real-world clinical outcomes with rivaroxaban versus warfarin in patients with NVAF and obesity according to the number of concurrent medications.

Methods

This retrospective cohort study identified patients with one or more pharmacy claim for rivaroxaban or warfarin from two large claims databases. Patients were required to have an atrial fibrillation diagnosis, body mass index ≥ 30 kg/m² and the presence of polypharmacy (1–4, 5–9, or ≥ 10 concurrent medications). Outcomes of stroke, systemic embolism, and major bleeding were compared between the rivaroxaban and warfarin cohorts after propensity score matching (PSM).

Results

A total of 95,875 patients were identified with one or more claim for either rivaroxaban or warfarin. After PSM, patient characteristics were balanced between cohorts (n = 21,547 in each cohort). The overall composite risk of stroke and systemic embolism was significantly lower in the rivaroxaban cohort compared with the warfarin cohort (hazard ratio [HR] 0.77, 95% confidence interval [CI] 0.70–0.84; p < 0.001). The risks of ischemic stroke, hemorrhagic stroke, and systemic embolism separately were also significantly reduced with rivaroxaban. Major bleeding risk was similar between cohorts (HR 0.93, 95% CI 0.81–1.06; p = 0.2842), and results were consistent across the three polypharmacy groups.

Conclusions

In this real-world study of NVAF patients with obesity, rivaroxaban was associated with lower risks of stroke and systemic embolism and similar risk of major bleeding versus warfarin across polypharmacy categories.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40256-021-00520-7.

Comparative Effectiveness and Safety of DOAC Versus Warfarin among Obese Patients with Atrial Fibrillation

Background

Obese patients are underrepresented in clinical trials assessing the comparative effectiveness and safety of use of direct oral anticoagulants vs use in atrial fibrillation (AF) patients.

Methods

Using data from Quebec provincial administrative databases, for the years2010-2017, we created a retrospective cohort of patients with inpatient or outpatient coding for AF and obesity who were newly prescribed an oral anticoagulant. The primary safety outcome was a composite of intracranial, gastrointestinal, and major bleeding from other sites, and the primary effectiveness outcome was a composite of ischemic stroke, systemic embolism, acute myocardial infarction, and death in the first year after oral anticoagulant initiation. Treatment groups were compared using inverse-probability-of-treatment-weighting Cox proportional-hazards models.

Results

A total of 2263 patients were included, of whom 1253, 403, and 539 filled a warfarin, standard-dose rivaroxaban, and standard-dose apixaban prescription, respectively. Standard-dose rivaroxaban was associated with a similar composite safety (hazard ratio [HR] 0.91; 95% confidence interval [CI] 0.44-1.91) and composite effectiveness risk (HR 1.42; 95% CI 0.99-2.04) compared to warfarin, whereas standard-dose apixaban was associated with a lower composite safety (HR 0.40; 95% CI 0.16-0.98) and similar composite effectiveness risk (HR 0.96; 95% CI 0.67-1.39).

Conclusion

Use of direct oral anticoagulants in obese AF patients was associated with a similar effectiveness and safety profile to that of warfarin use.

Inter- and intra-individual concentrations of direct oral anticoagulants: The KIDOAC study

BACKGROUND

Direct oral anticoagulants (DOACs) do not require concentration monitoring. However, whether DOAC concentrations are stable and their variation between and within patients is not well studied.

METHODS

Patients on vitamin K antagonists (VKA) who switched to rivaroxaban, apixaban, or dabigatran were included between 2018 and 2020. Blood was drawn at DOAC trough and peak concentrations at week 0, 2, and 8. Plasma drug concentrations were determined by anti-factor Xa concentrations (rivaroxaban, apixaban) or diluted thrombin time (dabigatran). Inter- and intra-individual variability was assessed by calculating the coefficient of variation (CV). Linear regression models were employed to evaluate associations between DOAC trough concentrations and previous VKA dosage, creatinine clearance, and body mass index (BMI).

RESULTS

One hundred fifty-two patients were included, of whom 96 (63%) were male and with a mean age of 73.9 ± 8.4 years. For the inter-individual variability, the CV ranged between 48% and 81% for trough values and between 25% and 69% for peak values among patients using the recommended DOAC dose. Intra-individual variability was substantially lower, as here the CV ranged between 18% and 33% for trough values and between 15% and 29% for peak values among patients using the recommended DOAC dose. Previous VKA dosage and creatinine clearance were inversely associated with DOAC trough concentrations. No association was found between BMI and DOAC trough concentrations.

CONCLUSION

Inter-individual variability of DOAC concentrations was higher than intra-individual variability. Lower previous VKA dosage and creatinine clearance were associated with higher DOAC trough concentrations. These findings support further study into an optimal target range, in which the risks of both bleeding and thrombosis are minimal.

Multi-center retrospective study evaluating the efficacy and safety of apixaban versus warfarin for treatment of venous thromboembolism in patients with severe obesity

STUDY OBJECTIVE

Direct oral anticoagulants are the standard of care for venous thromboembolism (VTE) treatment. These agents are recommended regardless of patient weight and body mass index (BMI). However, there remains limited evidence supporting the use of apixaban in patients with severe obesity with a BMI ≥40 kg/m² or weight ≥120 kg. The purpose of this study was to evaluate the efficacy and safety of apixaban for VTE in patients with a BMI ≥40 kg/m² or weight ≥120 kg.

DESIGN

This multi-center, retrospective study compared the use of apixaban versus warfarin in patients with severe obesity for the treatment of VTE between January 1, 2012, and December 31, 2019. Patients were identified by diagnosis codes for acute VTE and a weight ≥120 kg or BMI ≥40 kg/m² . The primary efficacy outcome was time to recurrence of VTE within 12 months, and the primary safety outcome was time to major bleeding within 12 months. Secondary outcomes included incidence of recurrent VTE, major bleeding, clinically relevant non-major bleeding (CRNMB), all-cause mortality, number of total hospital encounters, and switch in anticoagulant.

MAIN RESULTS

A total of 1099 patients were included in the study. Of these, 314 patients received apixaban and 785 received warfarin. The mean weight and BMI were 137 kg and 46 kg/m² , respectively. Time to recurrent VTE was significantly longer in those treated with apixaban compared to warfarin (p = 0.018). After controlling for confounding factors, apixaban use was associated with a reduced risk of recurrent VTE compared to warfarin (hazard ratio [HR] = 0.54, 95% confidence interval [CI]: 0.29-0.97, p = 0.04). There were no significant differences in major bleeding, CRNMB, or all-cause mortality between groups.

CONCLUSION

In patients with a BMI ≥40 kg/m² or weight ≥120 kg, apixaban appears to be effective and safe for the treatment of VTE.

Real life behaviour of direct oral anticoagulants in patients with nonvalvular atrial fibrillation and morbid obesity

Atrial fibrillation (AF) is the most prevalent arrhythmia worldwide and the main cause of anticoagulation, being direct oral anticoagulants (DOAC) increasingly used in this context. On the other hand, obesity is a known risk thromboembolic factor. In the clinical trials that led to the approval of DOAC for ischemic stroke prevention, patients with morbid obesity were underrepresented. The International Society of Thrombosis and Haemostasis suggests not using these drugs in morbid obese patients. Thus, the primary objectives of this study were to analyse the rates of mortality, thrombotic and haemorrhagic events in patients with morbid obesity. As secondary objectives, factors statistically associated with these events were analysed. Methods: multicentre retrospective study that included patients diagnosed with AF on treatment with DOAC from January 2013 to December 2016. The subgroup of patients with morbid obesity (BMI > 40 and / or weight > 120 kg) was analysed. Mean follow-up was 1.7 years. Results: Amongst 2,492 patients included in the study, 135 patients had morbid obesity (mean age was 71 ± 11 years). The mean scores of the CHA2DS2-VASc and HAS-BLED risk scales were 3.7 ± 1.6 and 2.2 ± 0.9, respectively. Neither differences were found regarding mortality (5.2 vs 6/100 patient-years, p = 0.662), ischemic stroke (0.8 vs 1.9/100 patient-years, p = 0.261) and major bleeding rates (3 vs 3.1/100 patient-years, p = 0.983) between morbidly obese population and general population. Nor was there an association found between the degree of obesity and any of the events studied. Conclusion: DOAC are safe and effective in morbidly obese patients.

Oral Anticoagulant Use in Morbid Obesity and Post Bariatric Surgery: A Review

Bariatric surgery has emerged as a therapy for obesity and the associated comorbidities. Obesity has been shown to be a risk factor for atrial fibrillation as well as venous thromboembolism, both of which are conditions that warrant anticoagulation. There is significant underrepresentation of the morbidly obese population in prospective trials that evaluated direct oral anticoagulants and vitamin K antagonists in atrial fibrillation and venous thromboembolism. We aim to review all the available data that assessed these oral anticoagulants in the morbidly obese population (body mass index >40 kg/m² and weight >120 kg) and in the post-bariatric surgery population. Our findings suggest that direct oral anticoagulants may be safe and effective for anticoagulation in morbidly obese patients for both atrial fibrillation and venous thromboembolism. However, warfarin is the preferred agent in the post-bariatric surgery population, given the limited number of studies on direct oral anticoagulants in this population. Further adequately powered randomized control trials are needed to confirm the safety and efficacy of these oral anticoagulants in the morbidly obese and post-bariatric surgery population.

Healthcare Resource Utilization and Costs of Rivaroxaban Versus Warfarin Among Nonvalvular Atrial Fibrillation Patients with Obesity and Diabetes

INTRODUCTION

Nonvalvular atrial fibrillation (NVAF) is associated with a substantial economic burden, particularly in patients with comorbid conditions. This study compared healthcare resource utilization (HRU) and costs of rivaroxaban and warfarin in patients with NVAF, obesity, and diabetes.

METHODS

A de-identified healthcare claims database was used to identify adult patients newly initiating rivaroxaban or warfarin and having at least one medical claim with a diagnosis of AF, obesity determined by validated algorithm, and at least one claim with a diagnosis of diabetes or for antidiabetic medication from December 2011 to March 2020. Propensity score matching was used to balance the treatment cohorts on the basis of demographics and baseline characteristics. All-cause and NVAF-related HRU rates and costs were compared between treatments using rate ratios, and mean cost differences were calculated on a per patient per year (PPPY) basis.

RESULTS

A total of 9999 matched pairs of patients with NVAF, obesity, and diabetes were identified in the rivaroxaban and warfarin cohorts. Rate ratios of all-cause HRU were significantly reduced with rivaroxaban versus warfarin in all healthcare settings evaluated, except emergency room visits. The greatest impact was on physician office visits followed by hospital outpatient and inpatient visits. NVAF-related HRU was significantly lower for rivaroxaban versus warfarin in all care settings. Consistent with these findings, the length of hospital stay was significantly reduced by approximately 4 days among all patients for both all-cause and NVAF-related hospitalizations in the rivaroxaban cohort compared with the warfarin cohort. Rivaroxaban was associated with reductions in all-cause total healthcare costs by more than $5000 PPPY and NVAF-related medical costs by approximately $1100 PPPY.

CONCLUSION

In comparison with warfarin, rivaroxaban reduced HRU and costs, particularly hospital inpatient and outpatient visits and physician office visits, in patients with NVAF and comorbidities of obesity and diabetes.

Apixaban and rivaroxaban use for atrial fibrillation in patients with obesity and BMI ≥50 kg/m2

BACKGROUND

Apixaban and rivaroxaban are increasingly used for thromboembolism prophylaxis in patients with non-valvular atrial fibrillation (NVAF) and commonly in patients with obesity and body mass index (BMI) ≥50 kg/m² despite the limited data.

OBJECTIVES

This study aimed to establish the effectiveness and safety of apixaban and rivaroxaban in patients with NVAF and BMI ≥50 kg/m² .

METHODS

A single health-system, retrospective cohort study evaluated the effectiveness and safety of apixaban and rivaroxaban initiated in adult patients (≥18 years of age) with BMI ≥50 kg/m² and NVAF. Outcomes of ischemic stroke, systemic embolic events, and bleeding were compared to a cohort of patients with BMI 18 to 30 kg/m² .

RESULTS

After 1619 patient-years worth of follow-up in 595 patients, the primary endpoint of incidence of ischemic stroke was numerically similar in both groups, 1.3 per 100 patient-years in the BMI ≥50 kg/m²  group, compared to 2.0 per 100 patient-years in the BMI <30 kg/m²  group (RR 0.65, 95% CI 0.38-1.82, p = 0.544). Incidence of major bleeding and clinically relevant non-major bleeding was also numerically similar between the two groups.

CONCLUSIONS

This study demonstrated that apixaban and rivaroxaban in patients with a BMI ≥50 kg/m² for treatment of NVAF may be safe and effective at preventing thromboembolic events and had no increased risk of bleeding. Although, findings should be interpreted with caution and confirmed with additional studies. This study contributes to the growing body of evidence that direct oral anticoagulants (DOACs) may be effective and safe to use for the treatment of NVAF in patients with BMI ≥50 kg/m² .

Clinical outcomes of dabigatran use in patients with non-valvular atrial fibrillation and weight >120 kg

BACKGROUND

Patients with obesity were underrepresented in studies evaluating the safety and effectiveness of direct oral anticoagulants (DOAC) in patients with non-valvular atrial fibrillation (NVAF). This study compared clinical outcomes in patients with NVAF and weighing >120 kg and ≤120 kg who were receiving dabigatran.

MATERIALS AND METHODS

This retrospective, matched, longitudinal cohort study included patients from three integrated healthcare delivery systems. Patients ≥18 years of age with NVAF were included if between September 1, 2016 and June 30, 2019 they received dabigatran. Patients >120 kg and ≤120 kg were matched up to 1:6 on age, sex, and CHA₂DS₂-VASc score. Data were extracted from administrative databases. The primary outcome was a composite of ischemic stroke, clinically-relevant bleeding, systemic embolism, and all-cause mortality. Multivariable regression analyses were performed.

RESULTS

777 and 3522 patients >120 kg and ≤120 kg, respectively, were matched. The >120 kg group tended to be younger with a higher burden of chronic disease. There was no difference between groups in the composite outcome (adjusted hazard ratio [AHR] 1.10, 95% confidence interval 0.89-1.37) or individual components of the composite. A subanalysis of clinically-relevant bleeding identified that patients >120 kg were at a greater risk of gastrointestinal bleeding (AHR 1.44, 95% CI 1.01-2.05).

CONCLUSIONS

In patients with NVAF and >120 kg, dabigatran use was associated with a small increased risk of gastrointestinal bleeding but no differences in stroke, mortality or clinically-relevant bleeding. These findings suggest that dabigatran use is reasonable in patients with NVAF and weight >120 kg.

Anticoagulation Treatment and Outcomes of Venous Thromboembolism by Weight and Body Mass Index: Insights From the Veterans Health Administration

BACKGROUND

Consensus statements have recommended against the use of direct oral anticoagulants (DOACs) in venous thromboembolism (VTE) for patients ≥120 kg and ≥40 kg/m². We sought to determine use and outcomes of DOACs for VTE across weight and body mass index (BMI).

METHODS

We performed a retrospective cohort study of patients with first-time VTE 2013 to 2018 that were treated with DOAC or warfarin in the Veterans Health Administration. The Veterans Health Administration has implemented system-wide guidance for patient selection and shared decision-making for use of DOACs in VTE at extremes of weight. We stratified patients by weight and BMI and assessed (1) association of weight and BMI category to outcomes in those prescribed DOAC; and (2) association of DOAC, as compared to warfarin, to outcomes by weight and BMI categories. Outcomes of interest included major bleeding, clinically relevant nonmajor bleeding, and recurrent VTE.

RESULTS

The analysis cohort included 51 871 patients prescribed DOAC or warfarin within 30 days of index VTE diagnosis (age 64.5±13.1 years; 6.0% female; median weight 93.4 kg [25th-75th: 80.5-108.6 kg]). For patients ≥120 kg (N=6934 patients), 38.4% were treated with DOAC, as compared to 45.4% of those ≥60 to <100 kg (N=30 645; P<0.0001). DOAC prescription was not associated with major bleeds, clinically relevant nonmajor bleeds, or recurrent VTE for those in higher weight and BMI categories as compared to those in average weight and BMI categories. DOAC prescription, as compared to warfarin, was not associated with increased recurrent VTE in any weight or BMI category.

CONCLUSIONS

Patients ≥120 kg and ≥40 kg/m² with VTE are frequently prescribed DOAC by the Veterans Health Administration, without an increase in bleeding or recurrent VTE. These findings suggest DOACs can be safe and effective in this population and may argue for broader adoption of pharmacy policies that promote careful patient selection and shared decision making.

Effectiveness and safety of rivaroxaban versus warfarin among nonvalvular atrial fibrillation patients with obesity and diabetes

AIMS

To compare clinical outcomes of rivaroxaban and warfarin in patients with nonvalvular atrial fibrillation (NVAF) and concurrent obesity and diabetes.

METHODS

Patients aged ≥18 years were identified from a healthcare claims database with the following criteria: newly initiating rivaroxaban or warfarin, ≥1 medical claim with a diagnosis of AF, obesity determined by validated machine learning algorithm, and ≥1 claim with a diagnosis of diabetes or for antidiabetic medication. Treatment cohorts were matched using propensity scores and were compared for stroke/systemic embolism (SE) and major bleeding using Cox proportional hazards models.

RESULTS

A total of 9999 matched pairs of NVAF patients with obesity and diabetes who initiated treatment with rivaroxaban or warfarin were included. The composite risk of stroke/SE was significantly lower in the rivaroxaban cohort compared with the warfarin cohort (HR 0.82; 95% CI 0.74-0.90). Risks of ischemic and hemorrhagic strokes were also significantly reduced with rivaroxaban versus warfarin, but not SE. Major bleeding risk was similar between treatment cohorts (HR 0.92; 95% CI 0.78-1.09).

CONCLUSIONS

In NVAF patients with comorbidities of obesity and diabetes, rivaroxaban was associated with lower risks of stroke/SE and similar risk of major bleeding versus warfarin.

Effectiveness of Direct Oral Anticoagulants in Obese Adults With Atrial Fibrillation: A Systematic Review of Systematic Reviews and Meta-Analysis

Background: Atrial Fibrillation (AF) is the most common sustained cardiac arrhythmia. Obesity is an independent risk factor for AF. Anticoagulants have been strongly recommended by all international guidelines to prevent stroke. However, altered pathophysiology in obese adults may influence anticoagulant pharmacology. Direct oral anticoagulants (DOACs) in the context of obesity and AF have been examined in recent systematic reviews. Despite the similarities in included studies, their results and conclusions do not agree.

Methods and Results: The protocol for this review was registered with PROSPERO (CRD42020181510). Seven key electronic databases were searched using search terms such as “atrial fibrillation,” “obese,^*” “overweight,” “novel oral anticoagulant,” “direct oral anticoagulant,” “DOAC,” “NOAC,” “apixaban,” dabigatran,” “rivaroxaban,” and “edoxaban” to locate published and unpublished studies. Only systematic reviews with meta-analyses that examined the effect of DOACs in overweight or obese adults with AF, published in the English language, were included. A total of 9,547 articles were initially retrieved. After removing the duplicates, title and abstract review and full-text review, five articles were included in the systematic review. From these only RCTs were included in the meta-analyses. There was disagreement within the published systematic reviews on DOACs in obesity. The results from our meta-analysis did not show any significant difference between all body mass index (BMI) groups for all outcomes at both 12 months and for the entire trial duration. Non-significant differences were seen among the different types of DOACs.

Conclusion: There was no difference between the BMI classes in any of the outcomes assessed. This may be due to the limited number of people in the trial that were in the obese class, especially obese class III. There is a need for large prospective trials to confirm which DOACs are safe and efficacious in the obese class III adults and at which dose.