Bleeding Risk Following Systemic Fluconazole or Topical Azoles in Patients with Atrial Fibrillation on Apixaban, Rivaroxaban, or Dabigatran

Concomitant Drug Interactions With Non-Vitamin K Oral Anticoagulants Are Associated With Bleeding and Mortality Risk in Patients With Nonvalvular Atrial Fibrillation

BACKGROUND

Non-vitamin K oral anticoagulants prevent stroke and systemic embolism in patients with nonvalvular atrial fibrillation. However, potential drug interactions with concomitant medications may compromise their efficacy and escalate the risk of adverse effects.

METHODS AND RESULTS

We conducted a territory-wide retrospective cohort study in Hong Kong, focusing on nonvalvular atrial fibrillation prescribed non-vitamin K oral anticoagulants. The objective was to investigate the associated risk of gastrointestinal bleeding, intracranial hemorrhage, hospitalization for major bleeding, and all-cause mortality in relation to various concomitant medications. Our analysis included 22 568 patients with nonvalvular atrial fibrillation (aged 75.7 ± 10.8 years; 51.2% men) taking non-vitamin K oral anticoagulants from January 1, 2017, to December 31, 2020, totaling 40 317 patient-years. It was found that amiodarone (hazard ratio [HR], 1.53), digoxin (HR, 1.30), diltiazem (HR, 1.18), clarithromycin (HR, 4.98), and fluconazole (HR, 2.38) were associated with increased gastrointestinal bleeding, whereas amiodarone (HR, 2.20) and digoxin (HR, 1.61) were associated with increased intracranial hemorrhage. Furthermore, amiodarone (HR, 1.64), digoxin (HR, 1.35), clarithromycin (HR, 4.18), and fluconazole (HR, 2.40) were associated with increased hospitalization for major bleeding. Additionally, amiodarone (HR, 2.65), digoxin (HR, 1.85), diltiazem (HR, 1.44), verapamil (HR, 1.80), antidepressants (HR, 1.31), and fluconazole (HR, 3.27) were associated with increased all-cause mortality. Conversely, dronedarone (HR, 0.56) and atorvastatin (HR, 0.86) were associated with a significant reduction in all-cause mortality.

CONCLUSIONS

For patients with nonvalvular atrial fibrillation taking non-vitamin K oral anticoagulants, several concurrent medications were associated with increased risks of intracranial hemorrhage, major bleeding hospitalizations, and overall mortality.

Critical considerations for co-administering rivaroxaban and vonoprazan: Unveiling potential pharmacokinetic interactions

To study the effects of metabolic enzyme activity inhibition and genetic polymorphisms on the pharmacokinetics and pharmacodynamics of rivaroxaban, we established an in vitro enzymatic reaction system to screen for inhibitors, and used the UPLC-MS/MS method to detect the levels of rivaroxaban and its metabolite M2-1. Additionally, in vivo pharmacokinetic-pharmacodynamic studies were conducted using Sprague-Dawley rats. Human recombinant CYP2J2 baculosomes were prepared using a baculovirus-insect expression system to investigate the impact of genetic polymorphisms on rivaroxaban metabolism through enzyme kinetics methods. The results demonstrated that acid-suppressing drugs strongly inhibited the metabolism of rivaroxaban in vitro. Among them, vonoprazan significantly increased the systemic exposure of rivaroxaban in vivo, while also prolonging prothrombin time, likely due to the competitive binding of vonoprazan and rivaroxaban to CYP2J2. Moreover, the genetic polymorphisms of CYP2J2 determined the metabolic characteristics of rivaroxaban and the inhibitory potency of vonoprazan. Overall, our findings suggest that vonoprazan-induced inhibition of CYP2J2 activity can affect the pharmacokinetics and pharmacodynamics of rivaroxaban, with the extent of inhibition determined by the genetic polymorphism of CYP2J2. These insights have important implications for the precise management of rivaroxaban in humans.

Potential interactions between antimicrobials and direct oral anticoagulants: Population-based cohort and case-crossover study

BACKGROUND

Although drug interactions between clarithromycin/erythromycin/fluconazole and direct oral anticoagulants (DOACs) are mechanistically plausible, it is uncertain whether they are clinically relevant.

OBJECTIVE

This study aims to investigate the association among coprescribed DOACs and antimicrobials and bleeding, cardiovascular disease and mortality.

METHODS

We identified DOAC users in the Clinical Practice Research Datalink Aurum from January 1, 2011 to March 29, 2021. We used a cohort design to estimate hazard ratios (HRs) for bleeding outcomes (intracranial bleeding, gastrointestinal bleeding, other bleeding), comparing DOACs + clarithromycin/erythromycin/fluconazole users with DOACs users not receiving these antimicrobials. Cardiovascular outcomes were ischaemic stroke, myocardial infarction, venous thromboembolism, cardiovascular mortality, and all-cause mortality. A 6-parameter case-crossover design comparing odds of exposure with different drug initiation patterns for all outcomes in hazard window vs referent window within an individual was also conducted.

RESULTS

Of 483,815 DOAC users, we identified 21,701 coprescribed clarithromycin, 4532 coprescribed erythromycin, and 4840 coprescribed fluconazole. We observed an increased risk of gastrointestinal bleeding over 7 days following coprescription of DOAC + erythromycin vs DOAC alone (HR 3.66; 99% confidence interval [CI] 1.27-10.51), with wide CIs in case-crossover analysis. No evidence of increased risk of bleeding outcomes was seen for DOAC + clarithromycin/fluconazole in cohort and case-crossover analyses. For cardiovascular outcomes, compared with DOAC alone, an increased risk of cardiovascular mortality with DOAC + clarithromycin (HR 3.36; 99% CI 1.73-6.52) and increased risk of all-cause mortality with DOAC + clarithromycin/erythromycin/fluconazole were observed in cohort analysis. However, similar risks were found when initiating erythromycin/fluconazole with and without DOACs.

CONCLUSION

We found no strong evidence of increased risks of bleeding and cardiovascular outcomes in DOACs + clarithromycin/fluconazole/erythromycin users except a possible short-term increased risk of gastrointestinal bleeding in DOACs + erythromycin users.

Effectiveness and Safety of Different Oral Anticoagulants with P-glycoprotein/ CYP3A4 Inhibitors: A Network Meta-analysis

BACKGROUND

Metabolism of oral anticoagulants (OAC) is affected by P-glycoprotein (P-gp)/ CYP3A4 enzyme. However, the P-gp/CYP3A4 inhibitors are unavoidably used with OACs.

METHODS

Medline, Cochrane, and Embase were systematically searched for randomized controlled trials and cohort studies from inception till 23rd November, 2022 to assess the safety and effectiveness of OACs when concomitantly used with P-gp/CYP3A4 inhibitors. The primary outcomes were major bleeding and gastrointestinal (GI) bleeding. Secondary outcomes were stroke/systemic embolism (SE), all-cause mortality, any bleeding as well as intracranial hemorrhage (ICH). We estimated summary odds ratios (OR) with 95% credible intervals (CI) using pairwise and network meta-analysis with random effects.

RESULTS

A total of 11 studies involving 37,973 patients were included. When concomitantly used with P-pg/ CYP3A4 inhibitors, network meta-analysis indicated that dabigatran, apixaban, and edoxaban were associated with significantly lower risk of major bleeding compared to rivaroxaban, with ORs of 0.56, 0.51 and 0.48, respectively. Rivaroxaban and dabigatran were associated with a significantly increased risk of GI bleeding than warfarin, apixaban and edoxaban. Dabigatran and apixaban were linked with significantly lower risk of any bleeding compared with warfarin (ORs were 0.75 and 0.68, respectively) or rivaroxaban (ORs were 0.67 and 0.60, respectively). Apixaban (OR 0.32) and edoxaban (OR 0.35) were associated with a lower risk of ICH compared with warfarin. There was no difference between any OACs in terms of stroke/SE or all-cause mortality.

CONCLUSION

When concomitantly used with P-gp/CYP3A4 inhibitors, apixaban and edoxaban were associated with a lower risk of bleeding, though no significant difference in effectiveness was observed among all OACs.

Managing the Drug-Drug Interaction With Apixaban and Primidone: A Case Report

The management of the drug-drug interaction (DDI) between primidone, a moderate to strong cytochrome P-450 (CYP) 3A4 inducer, and apixaban, a direct oral anticoagulant (DOAC) and CYP3A4 substrate is complex and limited evidence exists to guide management. This case report describes a 65-year-old male, receiving primidone for essential tremor who developed an acute venous thromboembolism (VTE) requiring oral anticoagulation. DOACs are preferred over vitamin K antagonists for acute VTE treatment. Based on patient-specific variables, provider preference, and the avoidance of other DDIs, apixaban was selected. Apixaban's package insert recommends avoiding use with concomitant strong P-gp and CYP3A4 inducers due to the decreased exposure to apixaban; however, no recommendations are available for drugs that are moderate to strong CYP3A4 inducers and lack P-gp effects. Given that phenobarbital is an active metabolite of primidone, extrapolation of evidence from such literature is theoretical but provides insight into the management of this multi-faceted DDI. In the absence of the ability to monitor plasma apixaban levels, a management strategy of avoidance with a washout period of primidone based on pharmacokinetic parameters was used in this case. Additional evidence is needed to clearly understand the degree of impact and clinical significance of the DDI between apixaban and primidone.

Pharmacological options for Candida albicans Endocarditis at the roadblock with irrecoverable prosthetics and drug interactions: a case report and review of literature

BACKGROUND

Candidemia is the fourth most common nosocomial bloodstream infection. Endocarditis from candidemia is a rare but possibly fatal complication. The efficacy of amphotericin and echinocandins for induction and azoles for suppression has been well studied. Source control of infection, including removal of foreign bodies, remains the cornerstone for the success of any antifungal therapy.

CASE PRESENTATION

We are describing a case of a 63-years old patient with multiple comorbidities who developed candidemia secondary to Candida albicans. The prospect of curing the fungemia was made difficult by prosthetic devices, including prosthetic heart valves, intracardiac defibrillator, and inferior vena filter, which could not be extracted due to poor cardiovascular status and higher postoperative mortality risk. Combination therapy with amphotericin and 5-Flucytosine (5FC) was used with the first recurrence. Suppression with fluconazole was contraindicated due to prolonged corrected QT (QTc) interval. Isavuconazole was employed for chronic lifelong suppression.

CONCLUSION

Retaining prosthetics in higher surgical risk patients presents us with unique clinical and pharmacological challenges regarding breakthrough infections, drug interaction, and side effects from prolonged suppressive therapies.

Heart Failure Following Anti-Inflammatory Medications in Patients With Type 2 Diabetes Mellitus

BACKGROUND

Fluid retention and endothelial dysfunction have been related to use of nonsteroidal anti-inflammatory drugs (NSAIDs), and type 2 diabetes mellitus (T2DM) has been linked to both a decline in kidney function and subclinical cardiomyopathy.

OBJECTIVES

The authors hypothesized that short-term use of NSAIDs could lead to subsequent development of incident heart failure (HF) in patients with T2DM.

METHODS

Using nationwide Danish registers, we identified patients diagnosed with T2DM during 1998 to 2021 and included patients without previous HF, rheumatic disease, or use of NSAIDs 120 days before diagnosis. Associations between NSAIDs and first-time HF hospitalization were investigated using a case-crossover design with 28-day exposure windows, and ORs with 95% CIs were reported.

RESULTS

Included were 331,189 patients with T2DM: 44.2% female, median age of 62 years (IQR: 52-71 years); 23,308 patients were hospitalized with HF during follow-up, and 16% of patients claimed at least 1 NSAID prescription within 1 year. Short-term use of NSAIDs was associated with increased risk of HF hospitalization (OR: 1.43; 95% CI: 1.27-1.63), most notably in subgroups with age ≥80 years (OR: 1.78; 95% CI: 1.39-2.28), elevated hemoglobin (Hb) A1c levels treated with 0 to 1 antidiabetic drug (OR: 1.68; 95% CI: 1.00-2.88), and without previous use of NSAIDs (OR: 2.71; 95% CI: 1.78-4.23).

CONCLUSIONS

NSAIDs were widely used and were associated with an increased risk of first-time HF hospitalization in patients with T2DM. Patients with advanced age, elevated HbA1c levels, and new users of NSAID seemed more susceptible. These findings could guide physicians prescribing NSAIDs.

Impact of concomitant fluconazole on direct oral anticoagulant bleeding risk

STUDY OBJECTIVE

The aim of this study was to evaluate the effect on bleeding risk when fluconazole is administered concomitantly with direct oral anticoagulants (DOACs).

DESIGN

This was a retrospective cohort study including hospitalized adult patients prescribed a DOAC with or without fluconazole.

SETTING

The Ohio State University Wexner Medical Center, a tertiary care academic medical center with more than 1800 beds.

PATIENTS

Hospitalized patients ages 18-89 years who received apixaban or rivaroxaban with or without fluconazole from October 1, 2016, to September 30, 2021, were included. The minimum duration of DOAC or DOAC with fluconazole therapy was 48 h. Patients were excluded if they received fluconazole <400 mg daily or a DOAC at doses outside those recommended for atrial fibrillation or venous thromboembolism treatment or prophylaxis. Patients were matched based on DOAC received.

INTERVENTION

Patients who received a DOAC with fluconazole were compared with those receiving a DOAC alone. The primary outcome was a composite of major, clinically relevant nonmajor, and minor bleeding events at 30 days.

MEASUREMENTS AND MAIN RESULTS

There were 216 patients included, 108 in the DOAC with fluconazole group and 108 in the DOAC alone group. More patients in the DOAC with fluconazole group experienced bleeding at 30 days compared with the DOAC alone group [35/108 (32%) vs. 21/108 (19%), respectively; p = 0.03]; however, after adjusting for proven confounding variables (hemoglobin and concomitant carvedilol) this was found not to be statistically significant [adjusted odds ratio 1.71, 95% confidence interval 0.85-3.40].

CONCLUSIONS

Patients receiving a DOAC with fluconazole were not at significantly increased risk for bleeding at 30 days compared with those receiving a DOAC alone after controlling for confounding variables. As an increasing number of patients are prescribed DOACs, the results of this study may inform clinical decision-making on the safety of concomitant DOAC and fluconazole use.

Drug-Drug Interactions of Direct Oral Anticoagulants (DOACs): From Pharmacological to Clinical Practice

The direct oral anticoagulants (DOACs), dabigatran, rivaroxaban, apixaban, and edoxaban, are becoming the most commonly prescribed drugs for preventing ischemic stroke in patients with non-valvular atrial fibrillation (NVAF) and for the treatment and prevention of venous thromboembolism (VTE). Rivaroxaban was also recently approved for the treatment of patients with a recent acute coronary syndrome (ACS). Their use demonstrated to have a favorable risk-benefit profile, with significant reductions in stroke, intracranial hemorrhage, and mortality compared to warfarin, but with increased gastrointestinal bleeding. Nevertheless, their safety profile is compromised in multimorbidity patients requiring contemporary administration of several drugs. Comorbidity and polypharmacy have a high prevalence in elderly patients, who are also more susceptible to bleeding events. The combination of multiple treatments can cause relevant drug–drug interactions (DDIs) by affecting the exposure or the pharmacological activities of DOACs. Although important differences of the pharmacokinetic (PK) properties can be observed between DOACs, all of them are substrate of P-glycoprotein (P-gp) and thus may interact with strong inducers or inhibitors of this drug transporter. On the contrary, rivaroxaban and, to a lower extent, apixaban, are also susceptible to drugs altering the cytochrome P450 isoenzyme (CYP) activities. In the present review, we summarize the potential DDI of DOACs with several classes of drugs that have been reported or have characteristics that may predict clinically significant DDIs when administered together with DOACs. Possible strategies, including dosage reduction, avoiding concomitant administration, or different time of treatment, will be also discussed to reduce the incidence of DDI with DOACs. Considering the available data from specific clinical trials or registries analysis, the use of DOACs is associated with fewer clinically relevant DDIs than warfarin, and their use represents an acceptable clinical choice. Nevertheless, DDIs can be significant in certain patient conditions so a careful evaluation should be made before prescribing a specific DOAC.