Efficacy and safety of rivaroxaban in patients with diabetes and nonvalvular atrial fibrillation: the Rivaroxaban Once-daily, Oral, Direct Factor Xa Inhibition Compared with Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation (ROCKET AF Trial)

Mejorar la prevención de la trombosis y las complicaciones cardiovasculares durante la pandemia de COVID-19

Las complicaciones cardiovasculares son frecuentes en el paciente con la enfermedad coronavírica de 2019 (COVID-19), y se asocian con una mayor mortalidad. Entre las complicaciones cardiovasculares, destacan el síndrome coronario agudo, el daño miocárdico agudo (elevación de troponinas con coronarias normales), arritmias (principalmente fibrilación auricular y arritmias ventriculares), insuficiencia cardiaca, pericarditis/derrame pericárdico y complicaciones tromboembólicas (tromboembolia arterial y venosa, trombosis microvascular, embolia pulmonar, ictus). Por lo tanto, uno de los objetivos del tratamiento del paciente con COVID-19, sobre todo en sus formas más graves, es la prevención de las complicaciones cardiovasculares y trombóticas, lo que sin duda tendría un impacto positivo en el pronóstico de estos pacientes.

Fuera de este contexto, los resultados provenientes tanto de ensayos clínicos como de estudios en la práctica clínica muestran que el rivaroxabán es eficaz y seguro en todo el espectro de la enfermedad cardiovascular (fibrilación auricular, enfermedad tromboembólica venosa y enfermedad cardiovascular ateroesclerótica), por lo que podría aportar un valor añadido en la prevención de las complicaciones trombóticas y cardiovasculares durante la pandemia de COVID-19.

Hematoma Risk After Needle Electromyography in Patients Using Newer Oral Anticoagulants

PURPOSE

To assess the safety of needle electromyography in patients on non-vitamin K oral anticoagulants (NOACs) compared with warfarin.

METHODS

A retrospective chart review was done in patients who underwent needle electromyography studies while they were using warfarin and NOACs. After the needle electromyography, all the patients were monitored for 2 hours and ultrasound of high-risk muscle groups was done. The complications were classified based on the International Society on Thrombosis and Hemostasis definitions.

RESULTS

Fifty-eight patients were included: 29 were using NOACs and the other 29 were on warfarin. The mean age was 59.33 ± 16 years. Hemorrhagic complications from needle electromyography were noted in 9 patients: 7 (77.7%) NOACs and 2 (22.3%) warfarin. Among them, 6 patients (66.6%) met the diagnostic criteria for Clinically Relevant Non-Major Bleeding criteria proposed by International Society on Thrombosis and Hemostasis and 3 patients (33.4%) had an asymptomatic hematoma on ultrasound evaluation. A total of 267 muscles were tested and only 9 (3.3%) muscles had hemorrhagic complications. One patient (rivaroxaban) had acute bleeding requiring pressure bandage, five patients (two apixaban, two rivaroxaban, and one warfarin) had clinical hematoma that required ice packs, and three patients (two rivaroxaban and one warfarin) had a hematoma on ultrasound of deep muscles.

CONCLUSIONS

Patients on NOACs had minimal risk of clinically relevant hemorrhagic complications, and the risk is not significantly different from those on warfarin.

Comparative effectiveness and safety of direct oral anticoagulants versus warfarin in UK patients with atrial fibrillation and type 2 diabetes: A retrospective cohort study

PURPOSE

To estimate the effectiveness and safety of direct oral anticoagulants (DOACs) compared with warfarin in AF patients with type 2 diabetes (T2DM).

METHODS

A retrospective cohort study was designed, using the UK Clinical Practice Research Datalink (August 2011-June 2018). Participants were 1-year naïve users of DOACs or warfarin, followed from the date of first prescription of an oral anticoagulant until the end of the study period, death, discontinuation of treatment, switching to another anticoagulant, or an outcome of interest, whichever came first. Cox regression analysis was performed to estimate the hazard ratio (HR) adjusted for potential confounders.

RESULTS

A total of 8555 patients were identified. No significant differences were found between DOACs and warfarin in the risk of stroke (adjusted HR 1.15; 95% CI 0.82-1.60), ischemic and unspecified stroke (adjusted HR 1.23; 95% CI 0.86-1.76) or haemorrhagic stroke (adjusted HR 0.75; 95% CI 0.30-1.85), and myocardial infarction (adjusted HR 1.39;95% CI 0.99-1.97). DOAC and warfarin users were comparable with respect to risk of major bleed (adjusted HR 0.83; 95% CI 0.68-1.03), intracranial bleeding (HR 0.66; 95% CI 0.34-1.30), gastrointestinal bleeding (HR 0.88; 95% CI 0.60-1.30), and bleeding on other clinically relevant sites (HR 0.89; 95% CI 0.60-1.31). In the subgroup analyses stratified by gender and diabetes severity, the risk for stroke and bleeding remained consistent.

CONCLUSION

DOACs are effective and safe alternatives to warfarin for the prevention of stroke in AF patients with T2DM.

Non-Vitamin K Antagonist Oral Anticoagulants in Secondary Stroke Prevention in Atrial Fibrillation Patients: An Updated Analysis by Adding Observational Studies

BACKGROUND

This meta-analysis aimed to evaluate the efficacy and safety of non-vitamin K antagonist oral anticoagulants (NOACs) versus vitamin K antagonists (VKAs) in secondary stroke prevention in atrial fibrillation (AF) patients.

METHODS

PubMed and Embase electronic databases were systematically searched from January 2009 to July 2019 for relevant randomized clinical trials and observational studies. A random-effects model was applied in the pooled analysis.

RESULTS

A total of 14 studies (4 randomized clinical trials and 10 observational studies) were included. Based on the randomized clinical trials, compared with VKA use, the use of NOACs was associated with decreased risk of stroke and systemic embolism, major bleeding, and intracranial bleeding. Based on the observational studies, compared with VKAs, the subgroup analysis showed that dabigatran and rivaroxaban were associated with a reduced risk of stroke or systemic embolism, whereas dabigatran and apixaban were associated with a decreased risk of major bleeding.

CONCLUSION

Based on current data, the use of NOACs is at least non-inferior to the use of VKAs in AF patients for secondary stroke prevention irrespective of NOAC type.

Does the presence of diabetes mellitus confer an increased risk of stroke in patients with atrial fibrillation on direct oral anticoagulants? A systematic review and meta-analysis

BACKGROUND AND AIMS

There is limited data on clinical outcomes in high risk groups such as patients with diabetes mellitus (DM) with atrial fibrillation (AF) on direct-acting oral anticoagulants (DOACs). Using a systematic review and meta-analysis of published studies, we aimed to determine the risk of stroke and other clinical outcomes in patients with AF on DOACs, with or without DM.

METHODS

Observational cohort studies reporting clinical outcomes in patients with AF on DOACs, with or without DM were identified from MEDLINE, Embase, Web of Science, the Cochrane Library, and search of bibliographies to April 2020. Summary measures of effect were relative risks with 95% confidence intervals (CIs).

RESULTS

Eight studies comprising of 4 observational cohorts (n = 76,260 participants) and 4 randomised controlled trials (RCTs) (n = 71,683 participants) were included. In RCTs, DOACs compared with warfarin reduced the risk of the composite outcome of stroke and systemic embolism, CVD death and intracranial bleeding in patients with DM: RRs (95% CIs) of 0.75 (0.62-0.90), 0.84 (0.72-0.97), and 0.57 (0.40-0.81) respectively. The corresponding estimates for patients without DM were 0.81 (0.68-0.96), 0.93 (0.80-1.08), and 0.47 (0.31-0.70) respectively. There was no evidence of interactions between DM status and effects of DOACs. The absolute reduction in clinical outcomes with DOACs compared to warfarin was greater in DM than without DM. Regardless of treatment strategy, interventional and observational evidence indicate that patients with DM had higher rates of stroke or systemic embolism, mortality and major bleeding compared to patients without DM.

CONCLUSIONS

Patients with AF and DM have increased risk of vascular events, which is reduced with the use of DOACs. The use of DOACs should be considered as an option in reducing the risk of stroke in these populations.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO 2020: CRD42020157196.

Patients with diabetes mellitus and atrial fibrillation treated with non-vitamin K antagonist oral anticoagulants: meta-analysis of eight outcomes in 58 634 patients across four randomized controlled trials

AIMS

Concomitant atrial fibrillation (AF) and diabetes mellitus (DM) increases the risk of stroke and systemic embolic events (SEE). This meta-analysis assessed the benefit/risk balance of non-vitamin K antagonist oral anticoagulants (NOACs) vs. warfarin, and explored whether there was effect modification by DM or heterogeneity in outcomes between NOACs in patients with and without DM.

METHODS AND RESULTS

We performed a meta-analysis of 58 634 patients from four Phase 3 trials of NOAC vs. warfarin in patients with AF, comparing the primary outcomes of efficacy and safety and six other secondary outcomes in patients stratified by the presence of DM. Interaction testing was used to assess for heterogeneity of treatment effects. A meta-regression was performed to evaluate the influence of baseline characteristics. NOACs reduced the risk of stroke/SEE in 18 134 patients with DM [hazard ratio (HR) 0.80; 95% confidence interval (CI) (0.69-0.93), I2 3.90] to a similar degree as in 40 500 patients without DM [HR 0.82; 95% CI (0.74-0.91), I2 16.33; P-int 0.81]. There was no effect modification of DM on the relative reduction with NOACs vs. warfarin in major bleeding (DM: 0.95, 95% CI 0.75-1.20, I2 43.83; no DM: 0.83, 95% CI 0.55-1.24; I2 87.90; P-int 0.37). Intracranial haemorrhage (HRs 0.51 and 0.47, P-int 0.70) and cardiovascular death (HRs 0.87 and 0.90, P-int 0.70) were significantly reduced by NOACs in the presence or absence of DM.

CONCLUSION

Non-vitamin K antagonist oral anticoagulants are more effective and safer than warfarin in AF patients with or without DM. Absent contraindications, NOACs should be the anticoagulation treatment choice in patients with diabetes.

Impact of Diabetes Mellitus on Stroke and Survival in Patients With Atrial Fibrillation

Although diabetes mellitus (DM) has been established as a risk factor for developing atrial fibrillation (AF) and is a known risk factor for stroke, it is unclear whether the presence or duration of DM is the primary adverse influence on the clinical course of AF. We retrospectively analyzed patients diagnosed with incident AF to examine the impact of DM on ischemic stroke and all-cause mortality. The diagnosis of DM was established by ICD-9 codes and review of medical records. To account for the significant differences in baseline characteristics of patients with and without diabetes, we matched 909 AF patients with DM with 909 AF patients without DM using propensity score matching based on 26 baseline variables. Cox regression analysis was used to identify independent factors associated with ischemic stroke and mortality. The mean age of the propensity matched cohort was 74 ± 11.5 years and 55.4% were male. Over a median follow-up period of 5.4 years (maximum 23.9 years), cumulative survival was significantly lower for patients with DM than those without DM; Log-rank p <0.001. In the propensity-matched comparison, the risk of mortality was significantly higher in the DM group compared with the non-DM group (hazard ratio 1.25; 95% confidence interval 1.12 to 1.69; p <0.001). Likewise, patients with DM had a higher risk of stroke (hazard ratio 1.32; 95% confidence interval 1.02 to 1.69; p = 0.03). Duration of DM was not associated with increased risk for stroke or mortality. In conclusion, the co-morbidity of DM represents an independent predictor of reduced survival and further highlights the excess risk of thromboembolism in patients with AF.

[Atrial Fibrillation and Diabetes Mellitus: the Control of Thromboembolic Risk]

Atrial fibrillation is one of the most common concomitant diseases in patients with diabetes mellitus (DM). Meta-analyses of multiple studies have shown that the risk of AF is higher for diabetic patients with impaired glucose homeostasis than for patients without DM. Patients with AF and DM were younger, more frequently had arterial hypertension, chronic kidney disease, heart failure, and ischemic heart disease, and stroke and were characterized with a more severe course of AF. The article discusses possible mechanisms of the mutually aggravating effects of DM and AF, scales for evaluating the risk of bleeding (CHADS2, CHA2DS2‑VASc, HAS-BLED), and the role of anticoagulants. A meta-analysis of 16 randomized clinical studies, including 9 874 patients, has demonstrated the efficacy of oral anticoagulants in prevention of stroke with an overall decrease in the relative risk by 62 % compared to placebo (95% confidence interval, from 48 to 72 ). For prevention of complications in patients with AF and DM, current antithrombotic therapies can be used, specifically the oral factor Xa inhibitor, rivaroxaban, which is the best studied in patients with AF and DM and represents a possible alternative to warfarin in such patients.

Efficacy and Safety of Direct Factor Xa Inhibitors Versus Warfarin in Prevention of Primary and Secondary Ischemic Strokes in Non-Valvular Atrial Fibrillation: A Literature Review

Ischemic stroke remains a major cause of mortality and morbidity in patients with atrial fibrillation. The use of appropriate anticoagulants reduces the risk of ischemic stroke in these patients. The current literature review is aimed to analyze the follow-up efficacy and safety of direct factor Xa inhibitors versus warfarin in the prevention of primary and secondary ischemic stroke, risk of major and minor bleedings, and food and drug interaction in patients with atrial fibrillation (AF). We selected PubMed as our database and we found 83,611 articles using the regular keyword 'atrial fibrillation'. We found 2,224 articles using the regular keywords 'direct factor Xa inhibitors' and 'atrial fibrillation'.

Finally, we obtained 326 studies using MeSH keywords: atrial fibrillation, direct factor Xa inhibitors, and warfarin. Ultimately, 46 articles were selected after applying the inclusion/exclusion criteria. All studies were randomized controlled trials (RCT) or clinical trials. Analysis of all studies showed that direct factor Xa inhibitors are superior to warfarin in the prevention of ischemic stroke in patients with non-valvular AF, with a lower rate of major and minor bleeding events and lower foods and drug interaction. Unlike warfarin, direct factor Xa inhibitors do not need frequent blood monitoring and dose adjustment. We found that warfarin and other vitamin K inhibitors may promote the calcification of heart valves and coronary arteries. There is some evidence that direct factor Xa inhibitors may slightly reverse these calcifications in coronary arteries and heart valves.

Direct oral anticoagulants across the heart failure spectrum: the precision medicine era

Heart failure (HF) is characterized by a pro-thrombotic state, which might aggravate its morbidity and, consequently, mortality. Several and commonly observed comorbidities, such as coronary artery disease, atrial fibrillation (AF), renal dysfunction, and diabetes often complicate HF, increasing the thromboembolic risk. In the past decade, direct oral anticoagulants (DOACs) have been approved for the treatment and prevention of stroke and embolic events in patients with nonvalvular AF. Due to their lower bleeding risk, these drugs are frequently used instead of warfarin; however, some controversies exist on their use in HF patients with or without comorbidities. Indeed, the management of anticoagulation in HF patients with underlying conditions is poorly investigated since these patients are underrepresented or excluded from randomized controlled trials. The aim of this research is to review current evidence on the use of DOACs in HF patients, also discussing their specific use in different clinical scenarios. Graphical abstract.

Effectiveness, safety, and major adverse limb events in atrial fibrillation patients with concomitant diabetes mellitus treated with non-vitamin K antagonist oral anticoagulants

BACKGROUND

Evidence of adverse clinical outcomes for non-vitamin K antagonist oral anticoagulant (NOACs) and warfarin in patients with atrial fibrillation (AF) and diabetes mellitus are limited. We investigated the effectiveness, safety, and major adverse limb events for NOACs versus warfarin among diabetic AF patients.

METHODS

In this nationwide retrospective cohort study collected from Taiwan National Health Insurance Research Database, we identified a total of 20,967 and 5812 consecutive AF patients with diabetes taking NOACs and warfarin from June 1, 2012, to December 31, 2017, respectively. We used propensity-score stabilized weighting to balance covariates across study groups.

RESULTS

NOAC was associated with a lower risk of major adverse cardiovascular events (MACE) (adjusted hazard ratio (aHR):0.88; [95% confidential interval (CI) 0.78-0.99]; P = 0.0283), major adverse limb events (MALE) (aHR:0.72;[95% CI 0.57-0.92]; P = 0.0083), and major bleeding (aHR:0.67;[95% CI 0.59-0.76]; P < 0.0001) compared to warfarin. NOACs decreased MACE in patients of ≥ 75 but not in those aged < 75 years (P interaction = 0.01), and in patients with ischemic heart disease (IHD) compared to those without IHD (P interaction < 0.01). For major adverse limb events, the advantage of risk reduction for NOAC over warfarin persisted in high risk subgroups including age ≥ 75 years, chronic kidney disease, IHD, peripheral artery disease, or use of concomitant antiplatelet drugs.

CONCLUSION

Among diabetic AF patients, NOACs were associated with a lower risk of thromboembolism, major bleeding, and major adverse limb events than warfarin. Thromboprophylaxis with NOACs should be considered in the diabetic AF population with a high atherosclerotic burden.

Effectiveness and Safety of Oral Anticoagulants in Patients With Nonvalvular Atrial Fibrillation and Diabetes Mellitus

OBJECTIVE

To address gaps in the data comparing non-vitamin K antagonist oral anticoagulants (NOACs) and warfarin among patients with nonvalvular atrial fibrillation (NVAF) and diabetes.

PATIENTS AND METHODS

A retrospective study was conducted on patients with NVAF and diabetes newly initiating apixaban, dabigatran, rivaroxaban, or warfarin from January 1, 2013, through September 30, 2015, with Medicare data from the US Centers for Medicare & Medicaid Services and 4 other US commercial claims databases. One-to-one propensity score matching was completed between NOACs and warfarin and between NOACs in each database, and the results were pooled. Cox proportional hazards models were used to evaluate the risk of stroke/systemic embolism (SE) and major bleeding (MB).

RESULTS

A total of 154,324 patients were included in the 6 matched cohorts, with a mean follow-up time of 6 to 8 months. Compared with warfarin, apixaban (hazard ratio [HR], 0.67; 95% CI, 0.57-0.77) and rivaroxaban (HR, 0.79; 95% CI, 0.71-0.89) were associated with a lower risk of stroke/SE; dabigatran (HR, 0.84; 95% CI, 0.67-1.07) was associated with a similar risk of stroke/SE. Apixaban (HR, 0.60; 95% CI, 0.56-0.65) and dabigatran (HR, 0.78; 95% CI, 0.69-0.88) were associated with a lower risk of MB; rivaroxaban (HR, 1.02; 95% CI, 0.94-1.10) was associated with a similar risk of MB compared with warfarin. Compared with dabigatran and rivaroxaban, apixaban was associated with a lower risk of MB. Compared with rivaroxaban, dabigatran was associated with a lower risk of MB.

CONCLUSION

This study-the largest observational study to date of patients with NVAF and diabetes taking anticoagulants-found that NOACs were associated with variable rates of stroke/SE and MB compared with warfarin.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT03087487.

Glycemic status and risks of thromboembolism and major bleeding in patients with atrial fibrillation

Background

Studies specifically examining the association between glycated hemoglobin A1c (HbA1c) levels and ischemic stroke/systemic thromboembolism (IS/SE) risk in atrial fibrillation (AF) patients are limited. Here, we investigated the association between HbA1c levels and the risk of IS/SE, as well as major bleeding, among AF patients with or without oral anticoagulants (OACs). We also compared the effectiveness and safety of warfarin and direct oral anticoagulants (DOACs) in different HbA1c categories.

Methods

We utilized medical data from a multi-center healthcare provider in Taiwan, which included 34,036 AF patients with serum HbA1c data available within 3 months after AF being diagnosed. Patients were divided into seven study groups according to their HbA1c levels: < 5.4%, 5.4%–5.6%, 5.7%–5.9%, 6.0%–6.4%, 6.5%–6.9%, 7.0%–7.9%, and ≥ 8.0%. The risks of IS/SE and major bleeding were compared among the groups after adjusting for baseline stroke and bleeding risk factors.

Results

Compared with the patients with HbA1c level < 5.4%, IS/SE risk significantly increased at HbA1c levels higher than 6.5% [adjusted hazard ratio (HR): 1.20, 95% confidence interval (CI): 1.00–1.43 for HbA1c level 6.5%–6.9%; 1.32, (95% CI 1.11–1.57) for HbA1c level 7.0%–7.9%; and 1.48 (95% CI 1.25–1.76) for HbA1c level ≥ 8.0%]. These results were generally consistent in AF patients without OACs (n = 24,931). However, among 9105 patients receiving OACs, IS/SE risk was not higher for patients having higher HbA1c levels. The risk of major bleeding was comparable across all HbA1c categories. Compared with warfarin, DOACs were associated with lower risks of IS/SE (adjusted HR: 0.61, 95% CI 0.49–0.75) and major bleeding (adjusted HR: 0.30, 95% CI 0.21–0.42) without interactions across different HbA1c categories (all P interactions > 0.05).

Conclusion

For AF patients, IS/SE risk significantly increased once HbA1c levels exceeded 6.5%, and OACs may attenuate these associations. Compared with warfarin, DOACs were more effective and safer across broad HbA1c categories. Therefore, in addition to prescribing DOACs when indicated, more aggressive glycemic control to achieve an HbA1c level < 6.5% may be considered for eligible AF patients and should be tested in further prospective studies.

[Risk of Coronary Events in Atrial Fibrillation]

It has been established that cardiovascular events due to coronary heart disease are highly prevalent in the population of patients with atrial fibrillation. In this review, pathophysiologic mechanisms explaining this association are detailed along with supporting epidemiological evidence. Various methods for the prediction and prevention of coronary events in atrial fibrillation are iscussed, including modification of shared risk factors, antithrombotic therapy and selection of the optimal direct oral anticoagulant in terms of favourable influence on ischemic cardiac outcomes.

Efficacy and safety of edoxaban in patients with diabetes mellitus in the ENGAGE AF-TIMI 48 trial

BACKGROUND

Diabetes mellitus is an independent risk factor for stroke and atrial fibrillation. Therefore, the risk/benefit profile of the oral factor Xa inhibitor edoxaban stratified by diabetes is of clinical interest.

METHODS

21,105 patients enrolled in ENGAGE AF-TIMI 48 were stratified into 2 pre-specified groups: without (N = 13,481) and with diabetes (N = 7,624).

RESULTS

On average, patients with diabetes were younger, and had a higher body mass index, CHA₂DS₂-VASc score and baseline endogenous Factor Xa activity. After multivariate adjustments, patients with diabetes had a similar rate of stroke and systemic embolism compared to those without diabetes (adjusted hazard ratio (HR_adj) 1.08; 95% confidence interval (CI) 0.94-1.24; p = 0.28). However, the risk of major bleeding was significantly higher in patients with diabetes (HR_adj 1.28; 95% CI 1.14-1.44; p < 0.001). The treatment effect of edoxaban (vs warfarin) was not modified by diabetes (all p-interactions > 0.05), a finding supported by the preserved edoxaban concentrations and inhibition of Factor Xa regardless of diabetes. The HRs of stroke and systemic embolism in patients receiving the higher-dose edoxaban regimen vs warfarin were 0.93 and 0.84 (p-interaction = 0.54) in those with and without diabetes respectively. The higher-dose edoxaban regimen reduced major bleeding (by 19-21%) and cardiovascular death (by 7-17%) regardless of diabetes (p-interactions = 0.81 and 0.33 respectively).

CONCLUSION

Patients with diabetes in ENGAGE AF-TIMI 48 had higher bleeding risk, but after adjustment similar stroke risk, compared to those without diabetes. The higher-dose edoxaban regimen had similar efficacy compared to warfarin, while reducing bleeding and cardiovascular mortality, irrespective of diabetes.

Association between hypocalcemia and rivaroxaban in coagulation disorders: a case report

We describe a patient with tertiary hyperparathyroidism with history of three episodes of deep vein thrombosis and on rivaroxaban. The patient underwent a subtotal parathyroidectomy, developing cervical hematoma with airway compression. Therefore, emergency surgical decompression was necessary. Later, on the ninth postoperative day, the serum ionized calcium levels were low. Medical team knowledge about preexisting diseases and their implication in the coagulation state are essential conditions to reduce morbidity and mortality of surgeries. However, no reports were found in literature about the association of hypocalcemia with the use of the new class of anticoagulants, which act as factor X inhibitors (Stuart-Prower factor), predisposing to increased bleeding in the immediate postoperative period.

LC-MS/MS method for simultaneous determination of rivaroxaban and metformin in rat plasma: application to pharmacokinetic interaction study

Aim: A reliable, sensitive and simple LC-MS/MS method has been established and validated for the quantitation of rivaroxaban (RIV) and metformin (MET) in rat plasma. Results: The procedure of method validation was conducted according to the guiding principles of EMA and US FDA. At the same time, the method was applied to pharmacokinetic interactions study between RIV and MET for the first time. When RIV and MET coadministered to rats, pharmacokinetic parameters of MET like AUC_(0-t), AUC_(0-∞) and C_max had statistically significant increased. t_max of RIV was prolonged without affecting t_1/2 obviously and C_max was inhibited significantly (p < 0.05) by comparison to the single group. Conclusion: The results indicated that drug-drug interactions occurred when the coadministration of RIV and MET.

Type 2 diabetes increases the long-term risk of heart failure and mortality in patients with atrial fibrillation

AIMS

Impact of type 2 diabetes mellitus (T2DM) on non-thromboembolic outcomes in atrial fibrillation (AF) is insufficiently explored. This prospective cohort study of AF patients aimed (i) to analyse the association between T2DM and heart failure (HF) events (including new-onset HF), and all-cause and cardiovascular mortality, (ii) to assess the impact of baseline T2DM treatment on outcomes, and (iii) to explore characteristics of new-onset HF phenotypes in relation to T2DM status.

METHODS AND RESULTS

Of 1803 AF patients (515/1288, with/without prior HF), 389 (22%) had T2DM at baseline. After 5 years of median follow-up, T2DM patients had an 85% greater risk of HF events [adjusted hazard ratio (aHR) 1.85; 95% confidence interval (CI) 1.51-2.28; P < 0.001], including a 45% increased risk for new-onset HF (1.45; 1.17-2.28; P = 0.015). T2DM conferred a 56% higher all-cause (1.56, 1.22-2.01; P = 0.003) and a 48% higher cardiovascular mortality (1.48; 1.34-1.93; P = 0.007). Fine-Gray analysis, with mortality as a competing risk, confirmed greater HF risk among T2DM patients. All risks were highest among insulin-treated patients. The prevalence of new-onset HF phenotypes was as follows: 67% preserved ejection fraction (HFpEF), 20% mid-range ejection fraction (HFmrEF) and 13% reduced ejection fraction (HFrEF). On time-dependent Cox regression, adjusted for baseline characteristics and an interim acute coronary event, T2DM increased aHRs for new-onset HFpEF (2.38; 1.30-4.58; P <0.001) and the combined HFmrEF/HFrEF (1.77; 1.11-3.62; P = 0.017).

CONCLUSIONS

Atrial fibrillation patients with T2DM have independently increased risk of new-onset/recurrent HF events, cardiovascular and all-cause mortality, particularly when insulin-treated. The prevailing phenotype of new-onset HF was HFpEF; T2DM conferred higher risk of both HFpEF and HFmrEF/HFrEF.

Type 2 Diabetes, Atrial Fibrillation, and Direct Oral Anticoagulation

Type 2 diabetes (T2D) is an independent risk factor of stroke and systemic embolism in patients with atrial fibrillation (AF), and T2D patients with AF-associated stroke seem to have worse clinical outcome and higher risk of unfavorable clinical course compared to individuals without this metabolic disorder. Long-term anticoagulation is indicated in majority of T2D patients with AF to prevent adverse AF-associated embolic events. Direct oral anticoagulants (DOACs), direct oral thrombin inhibitor dabigatran, and direct oral factor Xa inhibitors, rivaroxaban, apixaban, and edoxaban, have emerged as a preferred choice for long-term prevention of stroke in AF patients offering potent and predictable anticoagulation and a favorable pharmacology with low risk of interactions. This article reviews the current data regarding the use of DOACs in individuals with T2D and AF.

The continuous challenge of antithrombotic strategies in diabetes: focus on direct oral anticoagulants

Direct oral anticoagulants (DOACs) include dabigatran, which inhibits thrombin, and apixaban, edoxaban, and rivaroxaban, which inhibit factor Xa. They have been extensively studied in large trials involving patients affected by the most common cardiovascular diseases. As the presence of diabetes leads to peculiar changes in primary and secondary hemostasis, in this review we highlight the current evidence regarding DOAC use in diabetic patients included in the majority of recently conducted studies. Overall, in trials involving patients with atrial fibrillation, data seem to confirm at least a similar efficacy and safety of DOACs compared to warfarin in patients with or without diabetes. Furthermore, in diabetic patients, treatment with DOACs is associated with a significant relative reduction in vascular death compared to warfarin. In trials enrolling patients undergoing percutaneous coronary intervention, results concerning bleeding events are consistent in patients with or without diabetes. With regards to the COMPASS study, in patients with diabetes (n = 10,241), addition of rivaroxaban 2.5 mg to aspirin resulted in a significantly lower incidence of major adverse cardiovascular events (HR 0.74, 95% CI 0.61-0.90; interaction p = 0.68) with higher rates of major bleeding expected (HR 1.70, 95% CI 1.25-2.31). The 3287 patients with peripheral artery disease and diabetes receiving rivaroxaban plus aspirin had a twofold higher absolute reduction in the composite endpoint (cardiovascular death, myocardial infarction, and stroke) than patients without diabetes. Finally, we report the involvement of cytochromes or P-glycoprotein on the metabolism of the most commonly prescribed glucose-lowering drugs. No clinically relevant interactions are expected during the concomitant use of DOACs and anti-diabetic agents.

Geriatric Conditions and Prescription of Vitamin K Antagonists vs. Direct Oral Anticoagulants Among Older Patients With Atrial Fibrillation: SAGE-AF

Background: Geriatric conditions are common among patients with atrial fibrillation (AF) and relate to complications of oral anticoagulation (OAC).

Objective: To examine the prevalence of geriatric conditions among older patients with AF on OAC and relate type of OAC to geriatric conditions.

Methods: Participants had a diagnosis of AF, were aged ≥65 years, CHA₂DS₂VASC ≥ 2, and had no OAC contraindications. Participants completed a 6-component geriatric assessment that included validated measures of frailty (CHS Frailty Scale), cognitive function (MoCA), social support (MOS), depressive symptoms (PHQ9), vision, and hearing. Type of OAC prescribed was documented in medical records.

Results: 86% of participants were prescribed an OAC. These participants were on average aged 75.7 (SD: 7.1) years, 49% were women, two thirds were frail or pre-frail, and 44% received a DOAC. DOAC users were younger, had lower CHA₂DS₂VASC and HAS-BLED scores, and were less likely to be frail. In Massachusetts, pre-frailty was associated with a significantly lower odds of DOAC vs. VKA use (OR = 0.64, 95%CI 0.45, 0.91). Pre-frailty (OR = 0.33, 95%CI 0.18–0.59) and social isolation (OR = 0.38, 95%CI 0.14–0.99) were associated with lower odds of DOAC receipt in patients aged 75 years or older. Social isolation was associated with higher odds of DOAC use (OR = 2.13, 95%CI 1.05–4.29) in patients aged 65–74 years.

Conclusions: Geriatric conditions were common and related to type of OAC prescribed, differentially by age group. Research is needed to evaluate whether a geriatric examination can be used clinically to better inform OAC decision-making in older patients with AF.

Effectiveness and safety of rivaroxaban and warfarin for prevention of major adverse cardiovascular or limb events in patients with non-valvular atrial fibrillation and type 2 diabetes

AIMS

To assess the effectiveness and safety of rivaroxaban versus warfarin for the prevention of major adverse cardiovascular events (MACE) and major adverse limb events (MALE) in patients with type 2 diabetes (T2D) and non-valvular atrial fibrillation (NVAF).

MATERIALS AND METHODS

Using MarketScan data from January 2012 to December 2017, we identified oral anticoagulant-naïve patients with NVAF and comorbid T2D and ≥12 months of insurance coverage prior to rivaroxaban or warfarin initiation. Differences in baseline covariates between cohorts were adjusted for using inverse probability of treatment weights based on propensity scores (absolute standardized differences <0.1 achieved for all covariates after adjustment). Patients were followed until a MACE, MALE or major bleeding event, oral anticoagulant discontinuation/switch, insurance disenrolment or end of data availability. Hazard ratios (HRs) and 95% confidence intervals (CIs) comparing the cohorts were calculated using Cox regression.

RESULTS

We identified 10 700 rivaroxaban users (24.1% received a reduced dose) and 13 946 warfarin users. The median (25%, 75% range) age was 70 (62, 79) years, CHA2DS2-VASc score was 4 (3, 5) and duration of available follow-up was 1.4 (0.6, 2.7) years. Eleven percent of patients had peripheral artery disease, 5.1% had coronary artery disease, and 5.1% had a prior MALE, at baseline. Rivaroxaban was associated with a 25% (95% CI 4-41) reduced risk of MACE and a 63% (95% CI 35-79) reduced risk of MALE compared to warfarin. Major bleeding risk did not significantly differ between cohorts (HR 0.95).

CONCLUSIONS

Among patients with NVAF and T2D treated in routine practice, rivaroxaban was associated with lower risks of both MACE and MALE versus warfarin, with no significant difference in major bleeding.

Antithrombotic treatment gap among patients with atrial fibrillation and type 2 diabetes

BACKGROUND

We investigated the use of different antithrombotic therapies at baseline among patients with a history of atrial fibrillation (AF), type 2 diabetes, and established atherosclerotic cardiovascular disease (ASCVD) enrolled in the Trial Evaluating Cardiovascular Outcomes with Sitagliptin (TECOS).

METHODS

TECOS participants with a history of AF were stratified by CHA₂DS₂-VASc score and their antithrombotic use evaluated. Cox proportional hazards models were employed to explore possible associations between history of AF and prespecified clinical outcomes after adjusting for key baseline characteristics.

RESULTS

Of the 14,671 TECOS participants, 1167 (8%) had a history of AF, of whom 51.6% were using vitamin K antagonists (VKA); 31.2% used VKA alone, 16.9% used aspirin plus VKA, 1.8% used clopidogrel plus VKA, and 1.7% used aspirin and clopidogrel plus VKA. Aspirin was used by 56.8%: 30.9% used aspirin alone and 7.3% aspirin plus clopidogrel. Clopidogrel alone was used by 2.9%, and 7.3% were not using any antithrombotic medication. Participants with a history of AF had a higher risk of cardiovascular events, including hospitalization for heart failure and all-cause mortality, than those without AF. White, older men with prior myocardial infarction, heart failure, peripheral artery disease, or prior stroke were more likely to develop new-onset AF than others without these characteristics.

CONCLUSIONS

Almost half of high-risk AF patients with diabetes and established ASCVD in TECOS were not treated with anticoagulation therapy despite clear guideline recommendations for such therapy, highlighting the challenge and potential for clinical improvements in managing these patients in clinical practice.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00790205.

Rivaroxaban in atrial fibrillation cardioversion: an update

Currently, atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, with a prevalence of about 2–3% in the general population, representing a powerful risk factor for stroke and systemic thromboembolism and increased mortality and morbidity. Restoration of sinus rhythm is an important treatment option in AF and has a high success rate, but there is the need for an effective anticoagulation strategy to reduce the risk of embolic events. Anticoagulation with vitamin K antagonists is often associated with failure to achieving effective international normalized ratio. In this setting, recent data have led to extended approval for rivaroxaban in clinical practice, because it is effective and safe in patients with AF undergoing cardioversion, avoiding additional health costs and related time loss, while improving patient satisfaction. The present report provides an overview of the main randomized controlled trial and the main real-life studies, documenting the use of rivaroxaban in patients with non-valvular AF who underwent the cardioversion procedure. Considering that novel non-vitamin K antagonist oral anticoagulants in left atrial appendage thrombi resolution is still unknown in the real-world practice, the main findings on the use of rivaroxaban in this setting are also discussed.

Meta-analysis of Stroke and Bleeding Risk in Patients with Various Atrial Fibrillation Patterns Receiving Oral Anticoagulants

Oral anticoagulation therapy (OAT) is a mainstay for stroke prevention in atrial fibrillation (AF) patients. However, whether the risks of stroke/systemic embolic events (SEE) and bleeding events are affected by the type, duration, and frequency of AF in patients receiving OAT has been previously debated. We aimed to determine the risk of stroke/SEE and bleeding events associated with paroxysmal AF compared to persistent or permanent AF among patients who received OAT. Comprehensive literature searches of the Cochrane Library, PubMed/MEDLINE, and EMBASE databases were conducted from inception to July 2018. In total, 495 records were retrieved, of which 6 phase III randomized controlled trials (RCTs) focusing on the efficacy and safety of OAT in AF patients were ultimately evaluated and included. Among 70,447 AF patients, 15,028 (21.3%) patients had paroxysmal and 55,419 (78.7%) had persistent or permanent AF. Compared to persistent or permanent AF, the incidence of stroke/SEE was lower in paroxysmal AF patients (risk ratio [RR] 0.79, 95% confidence interval [CI] 0.71 to 0.88, P <0.00001, I² = 0%). Overall, all-cause mortality was also lower in paroxysmal AF than in persistent or permanent AF patients (RR 0.72, 95% CI 0.66 to 0.79, P <0.00001, I² =0%). Annualized major bleeding rates were similar across AF types (RR 1.06, 95% CI 0.96 to 1.17, P = 0.22, I ²= 35%). In conclusion, in patients with moderate-to-high risk of stroke receiving anticoagulation, those with paroxysmal AF have a lower risk of stroke, systemic embolism, and mortality but similar risk of major hemorrhage compared to persistent or permanent AF patients.

Direct Oral Anticoagulants in Patients Undergoing Spine Surgery

OBJECTIVE

Despite increasing use of direct oral anticoagulants (DOACs), guidelines for their perioperative use in spine surgery are still lacking. The main goal of our study was to analyze the occurrence of postoperative bleeding events and possible confounders in patients treated with DOACs who undergo spine surgery.

METHODS

Of 2777 patients undergoing spine surgery at our institution, 82 (2.9%) were treated with DOACs. The primary endpoint was postoperative bleeding events. Secondary outcome measures were postoperative thromboembolic events and anemia, hematologic findings, perioperative packed red blood cell substitution, operative time, hospital length of stay, morbidity, and mortality. Subanalysis of possible confounders affecting the rates of bleeding was also performed. Additionally, correlation of bleeding event rates and preoperative and postoperative discontinuation of DOACs was analyzed.

RESULTS

Overall postoperative bleeding events rate was 4.9% (n = 4). Preoperative DOAC discontinuation time of <24 hours increased significantly the rate of perioperative packed red blood cell substitution (P = 0.007). Treatment with concomitant blood thinners showed a trend toward higher incidence of bleeding events (P = 0.066), whereas pre-existing kidney failure increased significantly rates of postoperative anemia (P = 0.014). The rate of postoperative thromboembolic events was 4.9% (n = 4); all events occurred with DOAC resumption >72 hours postoperatively.

CONCLUSIONS

Short preoperative discontinuation time of DOACs, even <24 hours, may be justified, considering an increased risk of perioperative packed red blood cell substitution. Care should be taken with patients treated with concomitant blood thinners and patients with pre-existing kidney disease. Postoperative DOAC resumption >72 hours may increase risk of thromboembolic events.

Interventions for Preventing Thromboembolic Events in Patients With Atrial Fibrillation: A Systematic Review

BACKGROUND

The comparative safety and effectiveness of treatments to prevent thromboembolic complications in atrial fibrillation (AF) remain uncertain.

PURPOSE

To compare the effectiveness of medical and procedural therapies in preventing thromboembolic events and bleeding complications in adults with nonvalvular AF.

DATA SOURCES

English-language studies in several databases from 1 January 2000 to 14 February 2018.

STUDY SELECTION

Two reviewers independently screened citations to identify comparative studies of treatments to prevent stroke in adults with nonvalvular AF who reported thromboembolic or bleeding complications.

DATA EXTRACTION

Two reviewers independently abstracted data, assessed study quality and applicability, and rated strength of evidence.

DATA SYNTHESIS

Data from 220 articles were included. Dabigatran and apixaban were superior and rivaroxaban and edoxaban were similar to warfarin in preventing stroke or systemic embolism. Apixaban and edoxaban were superior and rivaroxaban and dabigatran were similar to warfarin in reducing the risk for major bleeding. Treatment effects with dabigatran were similar in patients with renal dysfunction (interaction P > 0.05), and patients younger than 75 years had lower bleeding rates with dabigatran (interaction P < 0.001). The benefit of treatment with apixaban was consistent in many subgroups, including those with renal impairment, diabetes, and prior stroke (interaction P > 0.05 for all). The greatest bleeding risk reduction was observed in patients with a glomerular filtration rate less than 50 mL/min/1.73 m2 (P = 0.003). Similar treatment effects were observed for rivaroxaban and edoxaban in patients with prior stroke, diabetes, or heart failure (interaction P > 0.05 for all).

LIMITATION

Heterogeneous study populations, interventions, and outcomes.

CONCLUSION

The available direct-acting oral anticoagulants (DOACs) are at least as effective and safe as warfarin for patients with nonvalvular AF. The DOACs had similar benefits across several patient subgroups and seemed safe and efficacious for a wide range of patients with nonvalvular AF.

PRIMARY FUNDING SOURCE

Patient-Centered Outcomes Research Institute. (PROSPERO: CRD42017069999).

Comparative Effectiveness and Safety of Rivaroxaban in Adults With Nonvalvular Atrial Fibrillation

BACKGROUND

All evidence regarding benefits and harms of rivaroxaban for stroke prevention has not been appraised yet.

STUDY QUESTION

What are the comparative effectiveness and safety of rivaroxaban in adults with nonvalvular atrial fibrillation?

DATA SOURCES

Randomized controlled trials (RCTs), meta-analyses, and observational studies were identified in several databases in October 2018.

STUDY DESIGN

Rapid review with evidence appraisal using the Grading of Recommendations Assessment, Development and Evaluation working group approach.

RESULTS

Two direct RCTs (23,021 patients) suggest that rivaroxaban is noninferior to warfarin in the prevention of stroke and systemic embolism (pooled relative risk [RR] 0.73, 95% confidence interval [CI], 0.43-1.24), reduces risk of hemorrhagic stroke (RR 0.59, 95% CI, 0.38-0.92), fatal bleeding (RR 0.49, 95% CI, 0.31-0.76), and cardiac arrest (RR 0.45, 95% CI, 0.25-0.82, 2 RCTs), but increases risk of major gastrointestinal bleeding (RR 1.46, 95% CI, 1.19-1.78). In observational studies, rivaroxaban is associated with lower risk of ischemic stroke (RR 0.87, 95% CI, 0.77-0.99, 222,750 patients), acute myocardial infarction (RR 0.61, 95% CI, 0.48-0.78, 73,739 patients), and intracranial hemorrhage (RR 0.64, 95% CI, 0.45-0.92, 197,506 patients) but higher risk of gastrointestinal bleeding (RR 1.30, 95% CI, 1.19-1.42, 188,968 patients) and higher risk of mortality when compared with warfarin in European studies (RR 1.19, 103,270 patients in the UK; RR 2.02, 22,358 patients in Denmark) but lower risk of mortality in Taiwan (RR 0.58, 40,000 patients). Network meta-analyses and observational studies suggest that rivaroxaban is associated with higher risk of bleeding when compared with apixaban (RR 2.14, 72,586 patients), dabigatran (RR 1.24, 67,102 patients), and edoxaban (RR 1.32, 71,683 patients).

CONCLUSIONS

Research on the long-term comparative effectiveness, safety, and effects on quality of life between rivaroxaban and other novel oral anticoagulants is urgently needed.

Direct oral anticoagulants for stroke prevention in atrial fibrillation: treatment outcomes and dosing in special populations

BACKGROUND

To review data from the pivotal phase III trials evaluating the efficacy and safety of direct oral anticoagulants (DOACs) versus warfarin for stroke prevention in patients with nonvalvular atrial fibrillation (NVAF), and to summarize the major findings with regards to patient subgroups that are at an increased risk for stroke or bleeding.

METHODS

A PubMed literature search (January 2009 to January 2017) was performed using the terms 'dabigatran', 'rivaroxaban', 'apixaban', 'edoxaban', 'atrial fibrillation', 'RE-LY', 'ROCKET AF', 'ARISTOTLE', and 'ENGAGE AF-TIMI 48'. All primary publications and secondary analyses in special populations at increased risk of stroke or bleeding from the pivotal phase III clinical trials were evaluated.

RESULTS

Available secondary analyses indicate no treatment interactions with regards to stroke or systemic embolic event (SEE) prevention for any of the DOACs in the patient subgroups, including patients with advanced age, impaired renal function, diabetes, prior stroke, concomitant antiplatelet therapy, heart failure, prior stroke, history of hypertension, myocardial infarction (MI), coronary artery disease, and peripheral artery disease (PAD). Although higher bleeding incidence was reported with dabigatran and rivaroxaban in patients aged 75 years and over with apixaban in patients with diabetes, and with rivaroxaban in patients with previous MI or PAD, no changes in dosing are recommended.

CONCLUSIONS

Overall, results of secondary analyses indicate that the recommended dosing strategy for each of the DOACs produces a consistent anticoagulant effect across a diverse patient population, including those at increased risk of stroke or bleeding.

Should we still be utilizing warfarin in the type 2 diabetic patient?

The frequency of non-valvular atrial fibrillation is increased by 40% in type 2 diabetic individuals and the thromboembolic risk associated with atrial fibrillation is increased by 79% compared with the non-diabetic individual with atrial fibrillation. Warfarin, the traditional anticoagulant used to prevent thromboembolism, is non-specific and affects several proteins outside the coagulation system. Decreasing the levels of matrix Gla protein entails an increase in coronary and renal artery calcification, which has the potential to increase cardiovascular events and accelerate decline in renal function. The direct-acting oral anticoagulants are specific, directly inhibiting either thrombin or factor Xa, and have been shown to be safer and more efficacious in studies of the type 2 diabetic patient.

Safety and effectiveness of rivaroxaban and warfarin in moderate-to-advanced CKD: real world data

BACKGROUND

In recent years, novel anticoagulant drugs have been introduced in the clinical armamentarium and have progressively gained momentum. Although their use is increasing among CKD patients, some skepticism about their risk-benefit ratio still persists. We sought to investigate the safety and effectiveness of rivaroxaban in a cohort of moderate-to-advanced CKD patients.

METHODS

This observational, retrospective, longitudinal study involved 347 consecutive CKD stage 3b-4 (according to NKF-KDOQI guidelines) patients enrolled from 8 cardiac outpatient clinics between March 2015 and October 2017. All patients received anticoagulation (100 warfarin vs. 247 rivaroxaban) as part of their non-valvular atrial fibrillation management at the attending physician's discretion. Clinical effectiveness (defined as the occurrence of ischemic stroke, venous thromboembolism, or transient ischemic attack) and safety (intracranial hemorrhage, gastrointestinal or other bleeding) were assessed separately.

RESULTS

Over a mean follow-up period of 16 ± 0.3 months, 25 stroke episodes (15 hemorrhagic, and 10 ischemic) occurred in 24 warfarin treated patients vs. none in the rivaroxaban arm. There were 5 vs. 0 episodes of deep venous thrombosis and 8 vs. 2 major episodes of bleeding in the warfarin and rivaroxaban groups, respectively. In contrast, the proportion of minor episodes of bleeding was similar between groups.

CONCLUSION

Rivaroxaban seems a safe and effective therapeutic option in CKD stage 3b-4 patients. However, future randomized controlled trials are needed to definitively establish the role of rivaroxaban in CKD patients.

Use of non-vitamin K oral anticoagulants in people with atrial fibrillation and diabetes mellitus

AIMS

To examine the efficacy and safety of non-vitamin K oral anticoagulants in people with both atrial fibrillation and diabetes mellitus.

METHODS

We reviewed efficacy and safety data from the warfarin-controlled phase III non-vitamin K oral anticoagulants trials (ARISTOTLE, RE-LY, ROCKET-AF, ENGAGE AF-TIMI 48) and their post hoc analyses with regard to diabetes status. We also reviewed the updated literature regarding this population.

RESULTS

At baseline 20-40% of the participants in the phase III non-vitamin K oral anticoagulants trials had diabetes mellitus at baseline. This population, in comparison with those without diabetes, was more likely to have other comorbidities, such as hypertension and coronary artery disease; thus, their cardiovascular risk was higher. Participants with diabetes had higher rates of stroke and systemic embolism than participants without diabetes. This risk was decreased using non-vitamin K oral anticoagulants, with no significant interaction by diabetic status or the specific drug used. Overall, compared with warfarin, non-vitamin K oral anticoagulants were safe and reduced the incidence of major bleeding in people with atrial fibrillation and diabetes, although the results varied with the different non-vitamin K oral anticoagulants.

CONCLUSIONS

The efficacy and safety of non-vitamin K oral anticoagulants compared with warfarin generally extend to participants with diabetes mellitus, although dedicated randomized trials or real-world data are lacking.

Direct oral anticoagulants versus warfarin for preventing stroke and systemic embolic events among atrial fibrillation patients with chronic kidney disease

BACKGROUND

Chronic kidney disease (CKD) is an independent risk factor for atrial fibrillation (AF), which is more prevalent among CKD patients than the general population. AF causes stroke or systemic embolism, leading to increased mortality. The conventional antithrombotic prophylaxis agent warfarin is often prescribed for the prevention of stroke, but risk of bleeding necessitates regular therapeutic monitoring. Recently developed direct oral anticoagulants (DOAC) are expected to be useful as alternatives to warfarin.

OBJECTIVES

To assess the efficacy and safety of DOAC including apixaban, dabigatran, edoxaban, and rivaroxaban versus warfarin among AF patients with CKD.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Specialised Register (up to 1 August 2017) through contact with the Information Specialist using search terms relevant to this review. Studies in the Specialised Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal, and ClinicalTrials.gov.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) which directly compared the efficacy and safety of direct oral anticoagulants (direct thrombin inhibitors or factor Xa inhibitors) with dose-adjusted warfarin for preventing stroke and systemic embolic events in non-valvular AF patients with CKD, defined as creatinine clearance (CrCl) or eGFR between 15 and 60 mL/min (CKD stage G3 and G4).

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies, assessed quality, and extracted data. We calculated the risk ratio (RR) and 95% confidence intervals (95% CI) for the association between anticoagulant therapy and all strokes and systemic embolic events as the primary efficacy outcome and major bleeding events as the primary safety outcome. Confidence in the evidence was assessing using GRADE.

MAIN RESULTS

Our review included 12,545 AF participants with CKD from five studies. All participants were randomised to either DOAC (apixaban, dabigatran, edoxaban, and rivaroxaban) or dose-adjusted warfarin. Four studies used a central, interactive, automated response system for allocation concealment while the other did not specify concealment methods. Four studies were blinded while the other was partially open-label. However, given that all studies involved blinded evaluation of outcome events, we considered the risk of bias to be low. We were unable to create funnel plots due to the small number of studies, thwarting assessment of publication bias. Study duration ranged from 1.8 to 2.8 years. The large majority of participants included in this study were CKD stage G3 (12,155), and a small number were stage G4 (390). Of 12,545 participants from five studies, a total of 321 cases (2.56%) of the primary efficacy outcome occurred per year. Further, of 12,521 participants from five studies, a total of 617 cases (4.93%) of the primary safety outcome occurred per year. DOAC appeared to probably reduce the incidence of stroke and systemic embolism events (5 studies, 12,545 participants: RR 0.81, 95% CI 0.65 to 1.00; moderate certainty evidence) and to slightly reduce the incidence of major bleeding events (5 studies, 12,521 participants: RR 0.79, 95% CI 0.59 to 1.04; low certainty evidence) in comparison with warfarin.

AUTHORS' CONCLUSIONS

Our findings indicate that DOAC are as likely as warfarin to prevent all strokes and systemic embolic events without increasing risk of major bleeding events among AF patients with kidney impairment. These findings should encourage physicians to prescribe DOAC in AF patients with CKD without fear of bleeding. The major limitation is that the results of this study chiefly reflect CKD stage G3. Application of the results to CKD stage G4 patients requires additional investigation. Furthermore, we could not assess CKD stage G5 patients. Future reviews should assess participants at more advanced CKD stages. Additionally, we could not conduct detailed analyses of subgroups and sensitivity analyses due to lack of data.

Comparative effectiveness of rivaroxaban in the treatment of nonvalvular atrial fibrillation

Rivaroxaban is a direct oral anticoagulant (DOAC) approved for the prevention of stroke and systemic embolism in patients with nonvalvular atrial fibrillation, a common arrhythmia. In this review, we summarize the effectiveness of rivaroxaban versus warfarin and the DOACs dabigatran, apixaban and edoxaban. The primary focus is on primary evidence from clinical trials, indirect comparison studies and real-world studies. While there are gaps in the literature, the evidence thus far indicates that rivaroxaban is superior to warfarin and similar to dabigatran, apixaban and edoxaban for the prevention of stroke or systemic embolism in patients with nonvalvular atrial fibrillation, although rivaroxaban may be associated with an elevated bleeding risk compared with other DOACs.

Novel Oral Anticoagulants in Patients Undergoing Cranial Surgery

BACKGROUND

The number of patients treated with novel oral anticoagulants (NOACs) is increasing. Despite growing clinical relevance, guidelines on the perioperative management of neurosurgical patients treated with NOACs are still lacking. The aim of this study was to analyze the occurrence of postoperative bleeding events and factors that might influence bleeding rates in these patients.

METHODS

Out of 1353 consecutive patients undergoing cranial neurosurgical procedures, 30 (2.2%) received NOACs preoperatively. The rates of perioperative and postoperative intracranial bleeding events, rate of postoperative thromboembolic events, hematologic findings, morbidity, and mortality were reviewed. A subanalysis of factors influencing the bleeding risk of these patients and the bleeding rate depending on the preoperative discontinuation time of NOACS, with cutoff of 24 and 48 hours, was performed as well.

RESULTS

The rate of perioperative bleeding was 13.3% (n = 4 of 30). Postoperative bleeding led to death in 2 patients. The median discontinuation time was significantly shorter in the patients experiencing a bleeding event compared to those without a bleeding event (1.5 days [range 0-3 days] vs. 11 days [range, 0-120 days]). The rate of perioperative thromboembolic events was 3.3% (n = 1), and overall mortality was 13.3% (n = 4).

CONCLUSIONS

The postoperative bleeding rate in patients undergoing cranial surgery treated with NOACs was 13.3%. A shorter preoperative discontinuation time seems to have a significant effect on bleeding rate. Further studies evaluating the management and postsurgical outcomes of these patients are warranted.

Vitamin K antagonists: relative strengths and weaknesses vs. direct oral anticoagulants for stroke prevention in patients with atrial fibrillation

Vitamin K antagonists (VKAs) have been the mainstay of anticoagulation therapy for more than 50 years. VKAs are mainly used for the prevention of stroke in patients with atrial fibrillation (AF) and the treatment and secondary prevention of venous thromboembolism. In the past 5 years, four new agents-the direct factor Xa inhibitors apixaban, edoxaban and rivaroxaban and the direct thrombin inhibitor dabigatran [collectively known as direct oral anticoagulants (DOACs) or non-VKA oral anticoagulants]-have been approved for these and other indications. Despite these new treatment options, the VKA warfarin currently remains the most frequently prescribed oral anticoagulant. The availability of DOACs provides an alternative management option for patients with AF, especially when the treating physician is hesitant to prescribe a VKA owing to associated limitations, such as food and drug interactions, and concerns about bleeding complications. Currently available real-world evidence shows that DOACs have similar or improved effectiveness and safety outcomes compared with warfarin. Treatment decisions on which DOAC is best suited for which patient to maximize safety and effectiveness should take into account not only clinically relevant patient characteristics but also patient preference. This article reviews and highlights real and perceived implications of VKAs for the prevention of stroke in patients with non-valvular AF, with specific reference to their strengths and weaknesses compared with DOACs.

Direct oral anticoagulants: an alternative treatment for thrombotic antiphospholipid syndrome?

Background

Direct oral anticoagulants (DOACs) demonstrate a lower risk–benefit ratio than vitamin K antagonists (VKAs) for secondary thromboprophylaxis of thrombotic events. But there are no data on the efficacy of DOACs for the prevention of thrombotic recurrence in patients with antiphospholipid syndrome (APS). In this study, we evaluated the efficacy of DOACs to prevent recurrences of thrombotic events in patients with APS.

Methods

This was a single-center pilot, using a multi-step Fleming design. If seven or fewer patients presented treatment failure with rivaroxaban, the study could conclude efficacy.

Results

A total of 23 patients were included. APS involved the veins only ( n = 19), arteries only ( n = 2) or both ( n = 1) and 1 patient exhibited catastrophic antiphospholipid syndrome (CAPS). Overall, two patients were positive for lupus anticoagulant, anti-beta-2 glycoprotein I antibodies and anticardiolipid antibodies (triple positivity). The mean duration of follow up was 35.6 (range, 29–40) months. A total of six treatment failures were reported: one patient, with triple positivity, developed bilateral distal pulmonary embolism (PE) after 20 months of treatment with rivaroxaban, two patients refused to take rivaroxaban, the treatment was stopped in three other patients: two with adverse effects and one with chronic iron-deficiency anemia.

Conclusions

Rivaroxaban may represent an alternative for secondary thromboprophylaxis for thrombo-embolism in patients with APS, in particular, those with poor international normalized ratio (INR) control and those who are not at the highest risk of recurrent thrombosis, such as those with triple positivity.

Comparison of the Incidence of Major Bleeding With Rivaroxaban Use Among Nonvalvular Atrial Fibrillation Patients With Versus Without Diabetes Mellitus

Diabetes mellitus (DM) is a common co-morbidity in those with nonvalvular atrial fibrillation (NVAF). Most patients with DM and NVAF have a CHA₂DS₂-VASc score of ≥1 and should be considered for oral anticoagulation therapy for stroke prevention per treatment guidelines. The most important risk associated with anticoagulation is bleeding, which may be higher in those with NVAF plus DM. Our objective was to evaluate the incidence and characteristics of major bleeding (MB) in rivaroxaban users diagnosed with NVAF, further comparing those with DM versus those without DM, in a real-world clinical setting. Electronic medical records of >10 million patients from the Department of Defense Military Health System were queried to identify rivaroxaban users with NVAF over a 2.5-year period. Major bleeding-related hospitalization was identified by a validated case-finding algorithm. Patient characteristics, incidence and management of MB, and fatal outcomes were assessed by DM status. Of 44,793 rivaroxaban users with NVAF, 12,039 (26.9%) had DM, who were more likely men, younger, with more co-morbidity and higher CHA₂DS₂-VASc scores. Major bleeding incidence was higher among those with DM compared with those without, 3.68 (95% confidence interval [CI] 3.37 to 4.03) versus 2.51 (95% CI 2.34 to 2.69) per 100 person-years, and intracranial bleeding incidence was 0.19 (95% CI 0.13 to 0.28) versus 0.25 (95% CI 0.20 to 0.31) per 100 person-years. Fatal outcomes were rare for both cohorts, 0.09 per 100 person-years. In conclusion, in this post-marketing study of 44,793 rivaroxaban users with NVAF, patients with DM had more co-morbidities and higher incidence of MB compared with those without DM.