Safety and efficacy of direct oral anticoagulants in comparison with warfarin across different BMI ranges: A systematic review and meta-analysis

Multivariate logistic regression analysis to explore the high-risk factors of deep vein embolism/pulmonary embolism after knee replacement in the elderly

ObjectiveThis study aims to identify and quantify the high-risk factors for deep vein thrombosis (DVT) and pulmonary embolism (PE) in elderly patients undergoing total knee replacement (TKA).Methods621 patients who underwent TKA were divided into DVT/PE positive group (N = 52) and a negative group (N = 569).ResultStatistically significant differences were observed in the following factors: Caprini score (χ2 = 11.385, p < .001), prevalence of chronic obstructive pulmonary disease (COPD) (χ2 = 4.502, p = .034), history of heart failure (χ2 = 4.326, p = .012), duration of surgery (t = 3.723, p = .002), and early postoperative activity (χ2 = 4.014, p = .045). The incidence of DVT/PE was significantly higher in the very high-risk group compared to the high-risk group (9.89% vs 4.84%, χ2 = 2.080, p = .032). Multivariate logistic regression analysis identified the Caprini score as an extremely high-risk factor (adjusted OR = 2.87, 95% CI: 1.53-5.39, p = .001), alongside COPD (OR = 1.94, 95% CI: 1.08-3.48, p = .026), history of heart failure (OR = 1.68, 95% CI: 1.01-2.78, p = .048), and surgical duration exceeding 2 hours (OR = 1.35, 95% CI: 1.08-1.68, p = .008) as independent risk factors. The model, developed using multi-factor regression variables, demonstrates strong predictive performance for the occurrence of DVT/PE, with an area under the receiver operating characteristic curve of 0.842 (95%CI: 0.791-0.894).ConclusionIn elderly patients undergoing TKA, even with standard anticoagulation prophylaxis, a high Caprini risk score, COPD, a history of heart failure, and prolonged operative time remain independent risk factors for DVT. Early postoperative mobilization has been shown to have a protective effect.

Effect of low-dose rivaroxaban on bleeding events in low-weight patients with nonvalvular atrial fibrillation: a retrospective propensity score-matched cohort study

Objective

To investigate the effect of low-dose rivaroxaban on bleeding events in low-weight patients with nonvalvular atrial fibrillation.

Methods

A retrospective study was conducted in patients with nonvalvular atrial fibrillation (weight ≤ 60 kg) who were admitted to the Department of Cardiology of Jiangxi Provincial People's Hospital from June 1, 2022, to December 12, 2022 and received anticoagulant therapy with rivaroxaban. The patients were divided into standard-dose group (15-20 mg) and low-dose group (10-15 mg). The patients were followed up for an average of 15 months by outpatient examination, telephone follow-up, or medical record inquiry of readmission patients. The bleeding events of the two groups were recorded during the follow-up period, and the two groups were balanced by propensity score weighting.

Results

A total of 198 patients with NVAF and body weight ≤60 kg receiving rivaroxaban anticoagulation therapy were enrolled, including 65 patients in the standard-dose group (15-20 mg) and 133 patients in the low-dose group (10-15 mg). In this study, only 24.1% (65/241) of the patients followed the standard dose of rivaroxaban. There was no significant difference in the incidence of bleeding events between the two groups after the balance of baseline characteristics (age) (P > 0.05). This was also consistent in patients weighing less than 50 kg.

Conclusions

In the real world, in lower-weight patients with nonvalvular atrial fibrillation, a reduced dose of rivaroxaban did not reduce the risk of bleeding, and this was consistent in patients weighing less than 50 kg.

Comparative Effectiveness and Safety of Direct Oral Anticoagulants Compared with Warfarin in Patients with Low Bodyweight who have Atrial Fibrillation: A Systematic Review and Meta-analysis

INTRODUCTION

oral anticoagulant (DOAC) agents are becoming the anticoagulation strategy of choice for most clinical risks for which they are indicated. However, residual uncertainty remains regarding their use in preventing stroke in patients with low bodyweight [< 60 kg or body mass index (BMI) < 18 kg/m2]. We have carried out pooled systematic analyses of published studies to determine the efficacy and safety of these agents compared with warfarin in stroke prevention in patients with low bodyweight.

METHODS

We carried out a comprehensive search of electronic databases from inception to June 2023 for eligible studies reporting on the efficacy and safety of direct oral anticoagulants versus warfarin in patients with atrial fibrillation who had low bodyweight. These include PubMed, EMBASE, the Cochrane Database of Systematic Reviews, the Science Citation Index, and the Database of Abstracts of Reviews of Effectiveness. Using the random effects model, derived pooled odd ratios (with their corresponding confidence intervals) of mortality outcomes in patient cohorts exposed to direct oral anticoagulants versus warfarin in patients with atrial fibrillation who had low bodyweight.

RESULTS

Nine studies (n = 159,514 patients) were included in our meta-analysis. DOAC analogs were associated with lower stroke recurrence compared with warfarin [odds ratio (OR) 0.66, 95% confidence interval (CI) 0.49-0.9]; however, there was no significant difference in the composite outcome (OR 0.81, 95% CI 0.59-1.09) and mortality (OR 0.82, 95% CI 0.48-1.41). Additionally, DOAC analogs showed a significant reduction in major bleeding events by 30% compared with warfarin (OR 0.70, 95% CI 0.62-0.80).

CONCLUSION

In this pooled meta-analytical synthesis of studies comprising both real-world and randomized controlled data, the use of DOAC analogs in patients with atrial fibrillation and low bodyweight (< 60 kg or BMI < 18 kg/m2) was associated with a significant reduction in risks of stroke and major bleeding compared with patient cohorts stabilized on warfarin-based therapy. There was uncertainty regarding the composite outcome and mortality point estimate between these two anticoagulation strategies. This finding helps to resolve the uncertainty associated with the use of DOACs in this cohort. Additionally, it suggests the need for confirmatory non-inferiority randomized controlled trials evaluating DOACs versus warfarin in this cohort of patients.

Real life results of direct-acting oral anticoagulants recommended-dose in obese vs normal-weight patients with venous thromboembolism

BACKGROUND

There is scarce evidence on the effectiveness and safety of recommended-dose direct acting oral anticoagulants (DOACs) in obese patients with venous thromboembolism (VTE).

MATERIAL AND METHODS

We used the data in the RIETE registry to compare the rates of VTE recurrences and major bleeding during long-term therapy with DOACs at recommended doses in patients with body mass index ≥30 kg/m2 (obese) vs. those with BMI 18.5-24.9 kg/m2 (normal weight). We performed regression models with competing risks for death.

RESULTS

From January 2013 through October 2022, 2885 obese patients and 2676 with normal weight in RIETE received rivaroxaban (n = 3020), apixaban (n = 1754), edoxaban (n = 636) or dabigatran (n = 151). Median age was 63 years and 52 % were female. At baseline, obese patients were more likely to have diabetes (18.6 % vs. 8.4 %), hypertension (51.9 % vs. 31.4 %) or pulmonary embolism (67.7 % vs. 61 %), and less likely to have renal insufficiency (5.3 % vs. 16 %) or anaemia (21.8 % vs. 28 %%). During anticoagulation (median, 147 vs. 101 days), the obese had a similar rate of VTE recurrences (1.71 vs. 2.14 events per 100 patients-years; hazard ratio (HR): 0.81; 95 % CI: 0.49-1.34) or major bleeding (1.45 vs. 1.76 per 100 patients-years; HR: 0.91; 95 % CI: 0.52-1.59) than those with normal weight. These findings persisted after multivariable analysis (recurrent VTE, HR: 0.80; 95 % CI: 0.48-1.32; major bleeding, HR: 1.11; 95 % CI: 0.60-2.07).

CONCLUSION

The use of DOACs at recommended doses in obese patients with VTE was associated with similar rates of VTE recurrences or major bleeding than in patients with normal weight.

Dilemmas Related to Direct-Acting Oral Anticoagulant Administration in Patients With Extreme Obesity

OBJECTIVE

The objective of the study was to discuss the controversies surrounding the use and dosing of direct-acting oral anticoagulants (DOACs) in obese patients recognizing the limitations of the existing evidence base that preclude strong recommendations.

DATA SOURCES

A literature search of MEDLINE was performed (2020 to end August 2022) subsequent to recent guidelines using the following search terms: direct acting anticoagulants, obesity, rivaroxaban, apixaban, edoxaban, dabigatran, dabigatran etexilate, and clinical practice guidelines.

STUDY SELECTION AND DATA ABSTRACTION

English-language studies and those conducted in adults were selected.

DATA SYNTHESIS

The available randomized studies evaluating DOACs had relatively small numbers of patients with more extreme forms of obesity (body mass index [BMI] > 40 kg/m²) and none of the larger studies had a specific focus on dosing DOACs in obese patients. Recent guidelines by the International Society on Thrombosis and Haemostasis (ISTH) have specific recommendations for dosing DOACs in obesity. There are pharmacokinetic/pharmacodynamic and observational studies published before and after the ISTH guidelines with a focus on DOAC dosing in obese patients that generally support the recommendations in the guidelines, but most involved small numbers of patients usually with BMIs <45 kg/m².

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

This review discusses DOAC dosing in obesity with important considerations for clinicians related to DOAC choice and dosing.

CONCLUSIONS

Dosing alterations of DOACs do not appear to be necessary when used for either prophylaxis or treatment in patients with BMIs up to approximately 45 to 50 kg/m², but research is needed for BMIs >50 kg/m².