Clinically relevant drug interactions between newer antidepressants and oral anticoagulants

Mechanism-based inactivation of cytochromes P450: implications in drug interactions and pharmacotherapy

Cytochrome P40 (CYP) enzymes dominate the metabolism of numerous endogenous and xenobiotic substances. While it is commonly believed that CYP-catalysed reactions result in the detoxication of foreign substances, these reactions can also yield reactive intermediates that can bind to cellular macromolecules to cause cytotoxicity or irreversibly inactivate CYPs that create them.Mechanism-based inactivation (MBI) produces either irreversible or quasi-irreversible inactivation and is commonly caused by CYP metabolic bioactivation to an electrophilic reactive intermediate. Many drugs that have been known to cause MBI in CYPs have been discovered as perpetrators in drug-drug interactions throughout the last 20-30 years.This review will highlight the key findings from the recent literature about the mechanisms of CYP enzyme inhibition, with a focus on the broad mechanistic elements of MBI for widely used drugs linked to the phenomenon. There will also be a brief discussion of the clinical or pharmacokinetic consequences of CYP inactivation with regard to drug interaction and toxicity risk.Gaining knowledge about the selective inactivation of CYPs by common therapeutic drugs helps with the assessment of factors that affect the systemic clearance of co-administered drugs and improves comprehension of anticipated interactions with other drugs or xenobiotics.

Exploring the impact of co-exposure timing on drug-drug interactions in signal detection through spontaneous reporting system databases: a scoping review

INTRODUCTION

Drug-drug interactions (DDIs) are defined as the pharmacological effects produced by the concomitant administration of two or more drugs. To minimize false positive signals and ensure their validity when analyzing Spontaneous Reporting System (SRS) databases, it has been suggested to incorporate key pharmacological principles, such as temporal plausibility.

AREAS COVERED

The scoping review of the literature was completed using MEDLINE from inception to March 2023. Included studies had to provide detailed methods for identifying DDIs in SRS databases. Any methodological approach and adverse event were accepted. Descriptive analyzes were excluded as we focused on automatic signal detection methods. The result is an overview of all the available methods for DDI signal detection in SRS databases, with a specific focus on the evaluation of the co-exposure time of the interacting drugs. It is worth noting that only a limited number of studies (n = 3) have attempted to address the issue of overlapping drug administration times.

EXPERT OPINION

Current guidelines for signal validation focus on factors like the number of reports and temporal association, but they lack guidance on addressing overlapping drug administration times, highlighting a need for further research and method development.

Analysis of Factors Affecting Concentrations and Concentration-To-Dose Ratios of Trazodone

BACKGROUND

Trazodone is prescribed for several clinical conditions. Multiple factors may affect trazodone to reach its therapeutic reference range. The concentration-to-dose (C/D) ratio can be used to facilitate the therapeutic drug monitoring of trazodone. The study aimed to investigate factors on the concentrations and C/D ratio of trazodone.

METHODS

This study analyzed the therapeutic drug monitoring electronic case information of inpatients in the First Hospital of Hebei Medical University from October 2021 to July 2023. Factors that could affect the concentrations and C/D ratio of trazodone were analyzed, including body mass index, sex, age, smoking, drinking, drug manufacturers, and concomitant drugs.

RESULTS

A total of 255 patients were analyzed. The mean age was 52.44 years, and 142 (55.69%) were women. The mean dose of trazodone was 115.29 mg. The mean concentration of trazodone was 748.28 ng/mL, which was in the therapeutic reference range (700-1000 ng/mL). 50.20% of patients reached the reference range, and some patients (36.86%) had concentrations below the reference range. The mean C/D ratio of trazodone was 6.76 (ng/mL)/(mg/d). A significant positive correlation was found between daily dose and trazodone concentrations (r 2 = 0.2885, P < 0.001). Trazodone concentrations were significantly affected by dosage, sex, smoking, drinking, and concomitant drugs of duloxetine or fluoxetine. After dosage emendation, besides the above factors, it was influenced by age ( P < 0.05, P < 0.01, or P < 0.001).

CONCLUSIONS

This study identified factors affecting trazodone concentrations and C/D ratio. The results can help clinicians closely monitor patients on trazodone therapy and maintain concentrations within the reference range.

Drug-drug interactions between COVID-19 drug therapies and antidepressants

INTRODUCTION

Antidepressants are widely used for the pharmacological treatment of anxiety and mood disorders. Since the eruption of the SARS-COV-2 pandemic and the later development of targeted treatments against COVID-19, inevitably many patients receive antidepressants as well as targeted treatments against COVID-19 against COVID-19. Co-administration of antidepressants with COVID-19 therapeutics has the potential of drug-drug interactions, of varying severity and clinical significance.

AREAS COVERED

This is a curated narrative review of the current state of the art regarding drug-drug interactions between COVID-19 therapeutics and medications licensed for the pharmacotherapy of depression. A systematic search of electronic databases, using as keywords the international nonproprietaty names of currently approved COVID-19 therapeutics and antidepressants was performed, and additionally online interaction checker tools were consulted. Derived data were synthesized for each COVID-19 therapeutic and presented with up-to-date guidance.

EXPERT OPINION

Several COVID-19 therapeutics have potential for drug-drug interactions with antidepressants. Remdesivir and Nirmatrelvir-Ritonavir have the higher risk, whereas several monoclonal antibodies appear safer. The most serious drug-drug interactions (serotonin syndrome and QTc prolongation) require close monitoring; however, DDI toward reducing the efficacy of antidepressants may be difficult to recognize. As COVID-19 treatment protocols take precedence, psychiatrists should exert flexibility in antidepressant use and proactively monitor treatment progress.

A meta-analysis on the association between SSRIs and blood pressure in patients with CVD and depression

OBJECTIVE

This meta-analysis aimed to explore the association between selective serotonine reuptake inhibitors (SSRIs) and blood pressure in patients with cardiovascular disease (CVD) and depression.

METHOD

This study was registered on PROSPERO (CRD42022368655) and conducted in accordance with PRISMA 2020. The databases included PubMed, Web of Science, and EMBASE. The inclusion date was from the inception date through Oct. 26, 2022.Review Manager version 5.3 and Stata version 12.0 were used for data analysis.

RESULTS

This meta-analysis included six studies, and a total number of 149 patients with CVD and depression . In the group analysis, SSRIs treatment had no effect on the systolic blood pressure (SBP) (MD = 1.01, 95%CI:-2.88, 4.90, P = 0.61) and diastolic blood pressure (DBP) (MD = 0.64, 95%CI:-1.03, 2.31, P = 0.45). In the subgroup analysis, SSRIs treatment had no effect on SBP for patients with hypertension (MD = -8.02, 95%CI:-16.84, 0.81, P = 0.08), and patients with other CVD (MD = 3.18, 95%CI:-1.15, 7.52, P = 0.15). For patients with hypertension, SSRIs treatment significantly lowered DBP (MD = -5.75, 95%CI:-10.84, -0.67, P = 0.03). But SSRIs treatment had no impact on DBP for patients with other CVD (MD = 1.41, 95%CI:-0.36, 3.18, P = 0.12). Subgroup analysis of the treatment period and the country had no significant impact on SBP and DBP. In the sensitivity analysis, there was no significant change after omitting one study in both SBP and DBP group analysis. Egger's test showed no publication bias of SBP (P = 0.183) and DBP group analysis (P = 0.392).

CONCLUSION

SSRIs help to lower DBP in hypertensive patients with depression. The potential pathophysiological mechanisms may lie in serotonin function, sympathetic activation and genetic heterogeneity. Further clinic and experimental researches need to be conducted on SSRIs and blood pressure.

Prescriptive behavior of non-vitamin K oral anticoagulants in patients affected by atrial fibrillation in general practice

Atrial fibrillation (AF) is the most common cardiac arrhythmia worldwide and in recent years the pharmacological approach has been strongly implemented; in Italy, the prescription of the non-vitamin K oral anticoagulants (NOAC) was also extended to General Practitioners (GPs) since 2020. The aim of the present study was to investigate the GPs prescribing behaviour of NOACs. An observational study was performed by using the computerized medical record of 14 GPs in Sicily: patients affected by AF were selected and stratified according to the prescribed antithrombotic drugs. Patients were considered inadequately managed if antithrombotic treatment was not adherent to recent ESC guidelines. A total of 467 (2.7 %) patients were affected by AF, 276 (59.1 %) were treated with an oral anticoagulant (OAC) regardless the high stroke risk (OR 1.64; 95 %CI 0.74-3.62; p = 0.226). The NOAC users were 236 patients as follow: Rivaroxaban 33.5 %, Apixaban 33,1 %, Dabigatran 17,4 %, Edoxaban 16.1 %. In 7 patients an inappropriate NOAC treatment was observed. Among Vitamin-K antagonist users, 25.0 % were considered inappropriate. Patients not treated with OAC were 191, of them 81.7 % were at high stroke risk and did not receive any OAC despite the indication to treat. In addition, the probability to be not properly managed significantly increased in older and in patients with atherosclerosis. Conversely, patients with at least one reported cardiology counselling significantly reduced the likelihood to be not properly managed (OR 0.38, 95 %CI 0.25-0.58; p 0.01). Our results suggest the need to optimize the management of real-life AF patients by improving prescribing adherence to ESC guidelines.

Depression and Anxiety in Heart Transplant Recipients: Prevalence and Impact on Post-Transplant Outcomes

BACKGROUND

Depression and anxiety (DA) are common mental disorders in patients with chronic diseases, but the research regarding their prevalence in heart transplantation (HTx) is still limited.

METHODS

We performed an analysis of the prevalence and prognostic relevance of DA in patients who underwent HTx between 2010 and 2018 in Germany. Data were obtained from Allgemeine Ortskrankenkasse (AOK), which is the largest public health insurance provider.

RESULTS

Overall, 694 patients were identified. More than a third of them were diagnosed with DA before undergoing HTx (n = 260, 37.5%). Patients with DA more often had an ischaemic cardiomyopathy (p < 0.001) and a history of previous myocardial infarction (p = 0.001) or stroke (p = 0.002). The prevalence of hypertension (p < 0.001), diabetes (p = 0.004), dyslipidaemia (p < 0.001) and chronic kidney disease (p = 0.003) was higher amongst transplant recipients with DA. Patients with DA were more likely to suffer an ischaemic stroke (p < 0.001) or haemorrhagic stroke (p = 0.032), or develop septicaemia (p = 0.050) during hospitalisation for HTx. Our analysis found no significant differences between the groups with respect to in-hospital mortality. The female sex and mechanical circulatory support were associated with an inferior prognosis. Pretransplant non-ischaemic cardiomyopathy was related to a favourable outcome.

CONCLUSIONS

DA affect up to a third of the population undergoing HTx, with a greater prevalence in patients with comorbidities. DA are associated with a higher incidence of stroke and septicaemia after HTx.

Personalizing Direct Oral Anticoagulant Therapy for a Diverse Population: Role of Race, Kidney Function, Drug Interactions, and Pharmacogenetics

Oral anticoagulants (OACs) are commonly used to reduce the risk of venous thromboembolism and the risk of stroke in patients with atrial fibrillation. Endorsed by the American Heart Association, American College of Cardiology, and the European Society of Cardiology, direct oral anticoagulants (DOACs) have displaced warfarin as the OAC of choice for both conditions, due to improved safety profiles, fewer drug-drug and drug-diet interactions, and lack of monitoring requirements. Despite their widespread use and improved safety over warfarin, DOAC-related bleeding remains a major concern for patients. DOACs have stable pharmacokinetics and pharmacodynamics; however, variability in DOAC response is common and may be attributed to numerous factors, including patient-specific factors, concomitant medications, comorbid conditions, and genetics. Although DOAC randomized controlled trials included patients of varying ages and levels of kidney function, they failed to include patients of diverse ancestries. Additionally, current evidence to support DOAC pharmacogenetic associations have primarily been derived from European and Asian individuals. Given differences in genotype frequencies and disease burden among patients of different biogeographic groups, future research must engage diverse populations to assess and quantify the impact of predictors on DOAC response. Current under-representation of patients from diverse racial groups does not allow for proper generalization of the influence of clinical and genetic factors in relation to DOAC variability. Herein, we discuss factors affecting DOAC response, such as age, sex, weight, kidney function, drug interactions, and pharmacogenetics, while offering a new perspective on the need for further research including frequently excluded groups.

Selective Serotonin Reuptake Inhibitor Use and Risk of Major Bleeding during Treatment with Vitamin K Antagonists: Results of A Cohort Study

BACKGROUND

 Selective serotonin reuptake inhibitors (SSRIs) may increase the risk of major bleeding by decreasing platelet function or decreasing vitamin K antagonist (VKA) metabolism via cytochrome P450 (CYP) inhibition.

AIMS

 To determine whether SSRIs are associated with major bleeding during VKA treatment and investigate the possible mechanisms.

METHODS

 In this cohort study, information on SSRI use and bleeding complications was obtained from patient records of VKA initiators between 2006 and 2018 from two anticoagulation clinics. Conditional logistic regression and time-dependent Cox regression were used to estimate the effect of SSRIs on a high international normalized ratio (INR ≥ 5) within 2 months after SSRI initiation and on major bleeding during the entire period of SSRI use, respectively. SSRI use was stratified for (non-)CYP2C9 inhibitors.

RESULTS

 A total of 58,918 patients were included, of whom 1,504 were SSRI users. SSRI initiation versus nonuse was associated with a 2.41-fold (95% confidence interval [CI]: 2.01-2.89) increased risk for a high INR, which was 3.14-fold (95% CI: 1.33-7.43) among CYP2C9-inhibiting SSRI users. The adjusted hazard ratio of major bleeding was 1.22 (95% CI: 0.99-1.50) in all SSRI users and 1.31 (95% CI: 0.62-2.72) in CYP2C9-inhibiting SSRI users compared with nonusers.

CONCLUSION

 SSRI use is associated with an increased risk of high INR and might be associated with major bleeding. The risk of a high INR was slightly more elevated for CYP2C9-inhibiting SSRI users, suggesting there might be a pharmacokinetic interaction (by CYP2C9 inhibition) next to a pharmacodynamic effect of SSRIs on platelet activation.

Advantages and Disadvantages of Using St. John's Wort as a Treatment for Depression

Background and objectives: St. John's wort (SJW) extracts are currently being used to treat depression of various degrees of severity. While many studies have shown it to be superior to placebo, data regarding the effectiveness of using SJW as a stand-alone treatment compared with standard antidepressants has yet to be proven conclusively. This study aims to understand the advantages and disadvantages of SJW as a treatment modality for depression.

Methods: The authors searched PubMed, JAMA network, Springer Link, Elsevier, Google Scholar, and Scientific Progress databases, from 2011 through August 2021, using the following keywords: St John’s wort, Hypericum perforatum, depression, antidepressant, complementary alternative medicine, economic evaluation depression St. wort, St John’s wort and depression, antidepressant interactions. This yielded a total of 27 papers following a thorough removal of irrelevant content and dissemination in languages other than English.

Results: In patients with mild and moderate depression, SJW proved superior to placebo. Certain studies comparing the efficacy of SJW versus selective serotonin reuptake inhibitors (SSRIs), especially fluoxetine, reported SJW to be more efficacious, while the majority reported no significant difference. Tricyclic antidepressants were also found to have similar efficacy as SJW. Moreover, treatment with SJW was also found to reduce postmenopausal depression. Regarding the safety profile, although SJW is better tolerated with fewer adverse effects when compared to standardized antidepressants, its predisposition to causing fatal serotonin syndrome, when used in conjunction with other serotonergic agents and drug interactions noted with CYP 450 drugs, raises a question in the safety profile.

Conclusion: It is essential to acknowledge that SJW has been used as a treatment measure in Germany. Despite being only listed as a dietary supplement by the FDA and not a drug, SJW has shown to be comparable, if not more efficacious, than most standard treatment options for depression. SJW does prove to be an exciting piece of pharmacotherapy in the realm of mental health and post-menopausal treatment. More prospective studies will help us better understand its efficacy in mild and moderate depression and its ability to serve as a long-term agent. Considering its mechanism of action, its role in relieving patients suffering from an anxiety disorder is also worth considering.

Hypericum perforatum and Its Potential Antiplatelet Effect

BACKGROUND

Hypericum perforatum (HP) is currently one of the most consumed medicinal plants in the world. In traditional Chinese medicine, the herb hypericum (Guan Ye Lian Qiao) belongs to the group of plants that clarify heat. It is also used to treat various types of infection and inflammation. In contrast to the extensive literature on the antidepressant effects of HP, little is known about its action on platelets. The main objective of this work was to investigate the possible relevance of HP to platelet function.

METHODS

We characterized the profile of platelet activation in the presence of HP extracts through an evaluation of molecular markers by flow cytometry: mobilization of intracellular Ca++ and expression of platelet receptors such as activated GPIIbIIIa and P-selectin (CD62).

RESULTS

The results indicated a possible inhibitory effect of HP on the platelet activation response, which could be explained by the effect on intracellular calcium mobilization and the expression of activated GPIIbIIIa receptors. Despite of the limitations of an in vitro study, our results provide evidence of the possible mechanisms of action of HP.

CONCLUSIONS

Further studies are needed to elucidate the effect of HP on hemostasis, but it may be recognized as a substance with antiplatelet properties.

Nonlinear Machine Learning in Warfarin Dose Prediction: Insights from Contemporary Modelling Studies

Objective: This study aimed to systematically assess the characteristics and risk of bias of previous studies that have investigated nonlinear machine learning algorithms for warfarin dose prediction. Methods: We systematically searched PubMed, Embase, Cochrane Library, Chinese National Knowledge Infrastructure (CNKI), China Biology Medicine (CBM), China Science and Technology Journal Database (VIP), and Wanfang Database up to March 2022. We assessed the general characteristics of the included studies with respect to the participants, predictors, model development, and model evaluation. The methodological quality of the studies was determined, and the risk of bias was evaluated using the Prediction model Risk of Bias Assessment Tool (PROBAST). Results: From a total of 8996 studies, 23 were assessed in this study, of which 23 (100%) were retrospective, and 11 studies focused on the Asian population. The most common demographic and clinical predictors were age (21/23, 91%), weight (17/23, 74%), height (12/23, 52%), and amiodarone combination (11/23, 48%), while CYP2C9 (14/23, 61%), VKORC1 (14/23, 61%), and CYP4F2 (5/23, 22%) were the most common genetic predictors. Of the included studies, the MAE ranged from 1.47 to 10.86 mg/week in model development studies, from 2.42 to 5.18 mg/week in model development with external validation (same data) studies, from 12.07 to 17.59 mg/week in model development with external validation (another data) studies, and from 4.40 to 4.84 mg/week in model external validation studies. All studies were evaluated as having a high risk of bias. Factors contributing to the risk of bias include inappropriate exclusion of participants (10/23, 43%), small sample size (15/23, 65%), poor handling of missing data (20/23, 87%), and incorrect method of selecting predictors (8/23, 35%). Conclusions: Most studies on nonlinear-machine-learning-based warfarin prediction models show poor methodological quality and have a high risk of bias. The analysis domain is the major contributor to the overall high risk of bias. External validity and model reproducibility are lacking in most studies. Future studies should focus on external validity, diminish risk of bias, and enhance real-world clinical relevance.

The use of serotonin reuptake inhibitors increases the risk of bleeding in patients with assist devices

Background

Bleedings are frequent and dreaded complications in heart failure patients with ventricular assist devices (VAD). Serotonin reuptake inhibitor (SRI) antidepressants are widely used to treat depression in these patients, though they are attributed an increased risk of bleeding due to their modification of hemostasis. Evidence on bleeding risk of VAD patients under SRI medication is scarce and limited. We therefore aimed to assess if SRI use is associated with an elevated bleeding risk in this particularly vulnerable population.

Methods

We analyzed the medical records of 92 VAD patients at the University Heart Center Zurich between September 2004 and April 2018 for the occurrence of bleedings and the concomitant use of an SRI. Bleeding was defined as any type of post-implantation bleeding requiring medical treatment. We performed univariate analyses and linear mixed-effects models, adjusting for baseline clinical characteristics as potential predictors to identify differences in bleeding rates in patients with vs. without SRI intake.

Results

The cohort comprised 60.9% of patients with a continuous-flow VAD and 39.1% with a pulsatile-flow VAD. A total of 77.2% of patients experienced at least one bleeding incident. Overall, 28.6% of bleedings occurred under SRI therapy. A generalized linear mixed model showed a predictive effect of SRI medication on bleeding rate, independent of VAD type (z = 2.091, p = 0.037).

Conclusions

Bleeding events in heart failure patients occur frequently after VAD implantation. Patients with SRI medication were at increased risk of bleeding. The indication and use of SRI, therefore, should be considered carefully.

Outcomes of Direct Oral Anticoagulants Co-Prescribed with Common Interacting Medications

Direct oral anticoagulants (DOACs) can potentially interact with multiple prescription medications. We examined the prevalence of co-prescription of DOACs with interacting medications and its impact on outcomes in patients with atrial fibrillation (AF). Patients with AF treated with a DOAC from 2010 to 2017 at the Mayo Clinic and co-prescribed medications that are inhibitors or inducers of the P-glycoprotein and/or Cytochrome P450 3A4 pathways were identified. The outcomes of stroke, transient ischemic attack, or systemic embolism, major bleeding, and minor bleeds were compared between patients with and without an enzyme inducer. Cox proportional hazards model was used to assess the association between interacting medications and outcomes. Of 8,576 patients with AF (mean age 70 ± 12 years, 35% female) prescribed a DOAC (38.6% apixaban, 35.8% rivaroxaban, 25.6% dabigatran), 2,610 (30.4%) were on at least 1 interacting agent: the majority were on an enzyme inhibitor (n = 2,592). Prescribed medications included non-dihydropyridine calcium channel blocker (n = 1,412; 16.5%), antiarrhythmic medication (n = 790; 9.2%), antidepressant (n = 659; 7.7%), antibiotic/antifungal (n = 77; 0.90%), antiepileptics (n = 17; 0.2%) and immunosuppressant medications (n = 19; 0.2%). Patients on an interacting medication were more likely to receive a lower dose of DOAC than indicated by the manufacturer's labeling (15.0% vs 11.4%, p <0.0001). In multivariable analysis, co-prescription of an enzyme inhibitor was not associated with risk of any bleeding (hazard ratio 0.87 [0.71 to 1.05], p = 0.15) or stroke, transient ischemic attack, or systemic embolism (hazard ratio 0.82 [0.51 to 1.31], p = 0.39). In conclusion, DOACs are co-prescribed with medications with potential interactions in 30.4% of patients with AF. Co-prescription of DOACs and these drugs are not associated with increased risk of adverse embolic or bleeding outcomes in our cohort.

Risk of Bleeding Associated with Antidepressant Drugs: The Competitive Impact of Antithrombotics in Quantitative Signal Detection

BACKGROUND

To date, disproportionality analysis has been unable to demonstrate the increased bleeding risk associated with antidepressant drugs, especially selective serotonin reuptake inhibitors.

OBJECTIVE

We hypothesised that a potential signal for an increased bleeding risk may be mitigated by the effects of agents other than antidepressant drugs that are strongly associated with haemorrhages, especially antithrombotics. In addition, we investigated if the use of more specific search terms of the Medical Dictionary for Regulatory Activities facilitates the detection of signals.

METHODS

Pharmacovigilance data from the Uppsala Monitoring Centre were used to calculate substance-specific reporting odds ratios (RORs) for all types of bleeding and gastrointestinal bleeding. Reporting odds ratios were calculated with and without antithrombotic comedication.

RESULTS

Regarding any type of bleeding, no signals were found in association with antidepressant drugs. Concerning upper gastrointestinal bleeding, signals were found related to citalopram (ROR: 1.56 [95% confidence interval 1.11-2.20]) and escitalopram (ROR: 1.52 [95% confidence interval 1.03-2.25]). After removal of reports related to antithrombotics, these signals could no longer be detected, but a new signal related to St. John's Wort associated with haemorrhages was found (ROR: 1.50 [95% confidence interval 1.21-1.86]).

CONCLUSIONS

Antithrombotics seem unlikely to have a major impact on the detection of the bleeding risk of antidepressant drugs. The different categorisation of adverse drug reactions regarding the strength of a causal relationship between a drug and an event in the database may be relevant for this negative finding.

Comparison of potential psychiatric drug interactions in six drug interaction database programs: A replication study after 2 years of updates

OBJECTIVE

Drug interaction database programs are a fundamental clinical tool. In 2018, we compared the category of potential drug-drug interaction (DDI) provided by six drug interaction database programs for 100 drug interaction pairs including psychiatric drugs, and found the category often differed. This study replicated the comparison in 2020 after 2 years of updates to all six drug interaction database programs.

METHODS

The 100 drug pairs included 94 different drugs: 67 pairs with a psychiatric and non-psychiatric drug, and 33 pairs with two psychiatric drugs. The assigned category of potential DDI for the drug pairs was compared using percent agreement and Fleiss kappa statistic of interrater reliability.

RESULTS

Despite 67 updates involving 46 of the 100 drug pairs, differences remained. The overall percent agreement among the six drug interaction database programs for the category of potential DDI was 67%. The interrater agreement results did not change. The Fleiss kappa overall interrater agreement was fair. The kappa agreement for a drug pair with any severe category rating was substantial, and the kappa agreement for a drug pair with any major category rating was fair.

CONCLUSIONS

Physicians should be aware of the inconsistency among drug interaction database programs in the category of potential DDI for drug pairs including psychiatric drugs. Additionally, the category of potential DDI for a drug pair may change over time. This study highlights the importance of ongoing international efforts to standardize methods used to define and classify potential DDI.

The Influence of Long-Term Treatment with Asenapine on Liver Cytochrome P450 Expression and Activity in the Rat. The Involvement of Different Mechanisms

Therapy of schizophrenia requires long-term treatment with a relevant antipsychotic drug to achieve a therapeutic effect. The aim of the present study was to investigate the influence of prolonged treatment with the atypical neuroleptic asenapine on the expression and activity of rat cytochrome P450 (CYP) in the liver. The experiment was carried out on male Wistar rats. Asenapine (0.3 mg/kg s.c.) was administered for two weeks. The levels of CYP mRNA protein and activity were determined in the liver and hormone concentrations were measured in the pituitary gland and blood serum. Asenapine significantly decreased the activity of CYP1A (caffeine 8-hydroxylation and 3-N-demethylation), CYP2B, CYP2C11 and CYP3A (testosterone hydroxylation at positions 16β; 2α and 16α; 2β and 6β, respectively). The neuroleptic did not affect the activity of CYP2A (testosterone 7α-hydroxylation), CYP2C6 (warfarin 7-hydroxylation) and CYP2E1 (chlorzoxazone 6-hydroxylation). The mRNA and protein levels of CYP1A2, CYP2B1, CYP2C11 and CYP3A1 were decreased, while those of CYP2B2 and CYP3A2 were not changed. Simultaneously, pituitary level of growth hormone-releasing hormone and serum concentrations of growth hormone and corticosterone were reduced, while that of triiodothyronine was enhanced. In conclusion, chronic treatment with asenapine down-regulates liver cytochrome P450 enzymes, which involves neuroendocrine mechanisms. Thus, chronic asenapine treatment may slow the metabolism of CYP1A, CYP2B, CYP2C11 and CYP3A substrates (steroids and drugs). Since asenapine is metabolized by CYP1A and CYP3A, the neuroleptic may inhibit its own metabolism, therefore, the plasma concentration of asenapine in patients after prolonged treatment may be higher than expected based on a single dose.

Drug repurposing of selective serotonin reuptake inhibitors: Could these drugs help fight COVID-19 and save lives?

The current 2019 novel coronavirus disease (COVID-19), an emerging infectious disease, is undoubtedly the most challenging pandemic in the 21st century. A total of 92,977,768 confirmed cases of COVID-19 and 1,991,289 deaths were reported globally up to January 14, 2021. COVID-19 also affects people's mental health and quality of life. At present, there is no effective therapeutic strategy for the management of this disease. Therefore, in the absence of a specific vaccine or curative treatment, it is an urgent need to identify safe, effective and globally available drugs for reducing COVID-19 morbidity and fatalities. In this review, we focus on selective serotonin reuptake inhibitors (SSRIs: a class of antidepressant drugs with widespread availability and an optimal tolerability profile) that can potentially be repurposed for COVID-19 and are currently being tested in clinical trials. We also summarize the existing literature on what is known about the link between serotonin (5-HT) and the immune system. From the evidence reviewed here, we propose fluoxetine as an adjuvant therapeutic agent for COVID-19 based on its known immunomodulatory, anti-inflammatory and antiviral properties. Fluoxetine may potentially reduce pro-inflammatory chemokine/cytokines levels (such as CCL-2, IL-6, and TNF-α) in COVID-19 patients. Furthermore, fluoxetine may help to attenuate neurological complications of COVID-19.

Association of Type of Antidepressant Initiation with Bleeding Risk in Atrial Fibrillation Patients Taking Oral Anticoagulants

Background

Inconsistent evidence suggests that use of certain antidepressants, particularly selective serotonin reuptake inhibitors (SSRIs), in patients using oral anticoagulants (OACs) might be associated with an elevated risk of bleeding.

Objective

This study aims to investigate the risk of bleeding associated with initiation of different types of antidepressants among atrial fibrillation (AF) patients on OAC therapy.

Patients and methods

A total of 30,336 AF patients (mean age 72.2 years; 54% female) on OAC therapy that started antidepressant treatment were identified from the Truven Health Analytics MarketScan Commercial and Medicare Databases for the period 2007–2015. Exposure was defined as filling a prescription for antidepressant, and categorized as SSRI, serotonin/norepinephrine reuptake inhibitors (SNRIs), serotonin reuptake inhibitors (SRIs), tricyclic antidepressants (TCAs), or other antidepressants. The primary outcome was incident hospitalized bleeding. Associations of antidepressant type with bleeding were assessed calculating hazard ratios (HRs) and 95% confidence intervals (CIs) with adjusted Cox models in pairwise propensity score-matched cohorts.

Results

During a mean follow-up of 21 months, we identified 1612 bleeding episodes. In pairwise comparisons, SSRI use was associated with an increased risk of bleeding when compared to most other antidepressants (HR 1.22, 95% CI 0.96–1.54 vs SNRI; HR 1.10, 95% CI 0.90–1.35 vs SRI; HR 1.03, 95% CI 0.82–1.30 vs TCA). SNRI use was associated with the lowest bleeding risk. Results did not differ by OAC type, age, and sex.

Conclusions

Among AF patients on OAC initiating antidepressants, risk of bleeding varied across antidepressant type. This information can inform treatment choices among patients receiving OAC.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40801-021-00258-3.

Comparison of potential pharmacokinetic drug interactions in patients with atrial fibrillation and changing from warfarin to non-vitamin K oral anticoagulant therapy

There are now anticoagulant choices with proposed advantages of non-vitamin K oral anticoagulants (NOACs) over warfarin being less routine monitoring and less drug interactions. Interacting medication can impact the efficacy and safety of anticoagulant therapy with management remaining clinically challenging. There have been limited studies comparing the potential for pharmacokinetic (PK) drug interactions between different anticoagulants. Therefore, the aim of this study was to compare potential PK interactions in patients with atrial fibrillation (AF) changing from warfarin to NOAC therapy. A retrospective analysis was conducted of patients with AF enrolled in a dedicated warfarin program but exiting this program to commence a NOAC. Patient data was collected, and concurrent medications were utilised to identify potential PK drug interactions with both warfarin and the chosen NOAC therapy. Patients were grouped according to the number of medications with potential PK interactions and comparisons made between groups. Of the 712 eligible patients who ceased warfarin to commence a NOAC, most commenced either apixaban (45.9%) or rivaroxaban (41.9%). When comparing warfarin to NOACs, there were significant differences in the proportion of patients taking no medication with potential PK drug interactions (46.9% vs 62.8%, p < 0.0001), and taking one (35.2% vs 28.5%, p = 0.0067) and two (14.5% vs 7.3%, p < 0.0001) potentially PK interacting medications. This study found when patients with AF were switched from warfarin to a NOAC, the potential for PK drug interactions significantly reduced but remained around 40%. Identifying and managing potential PK drug interactions with NOACs remains a priority to optimise clinical benefit of these anticoagulants.

The efficacy and safety of agomelatine, sertraline, and escitalopram for senile post-stroke depression: A randomized double-blind placebo-controlled trial

OBJECTIVES

This study aims to investigate the efficacy and safety of agomelatine, sertraline, and escitalopram for patients with senile post-stroke depression (SPSD, aged over 65 years).

PATIENTS AND METHODS

A total of 165 patients (aged over 65 years) with post-stroke depression (PSD) were recruited. These patients were randomly assigned to one of four groups and given an anti-depressant or a placebo as follows: group A (agomelatine in combination with conventional cerebrovascular disease medication) 48 patients; group B (sertraline in combination with conventional cerebrovascular disease medication) 47 patients; group C (escitalopram in combination with conventional cerebrovascular disease medication) 50 patients; and, a control group (conventional treatment alone) 20 patients. The efficacy of the different treatments was evaluated using the Hamilton Depression Scale (HAMD), the National Institute of Health Stroke Scale (NIHSS), and the Activities of Daily Living (ADL) Barthel index (BI) at one, two, four, and six weeks after treatment began.

RESULTS

According to the HAMD, NIHSS score, and BI index, the patients who received one of the three antidepressant treatments showed significant improvement compared with the control group (p < 0.05), but there was no significant difference between the three groups receiving anti-depressant medication (p > 0.05). Laboratory tests showed that the general adverse effects of the treatments were mild in all three groups, and patients generally tolerated the treatments.

CONCLUSION

A decrease of HAMD and NIHSS scores and an increase in the BI index could be observed in the patients receiving agomelatine, sertraline, or escitalopram treatment. Thus, it would appear that the condition of SPSD in older patients can be improved with the use of either agomelatine, sertraline, or escitalopram.

Adverse drug reactions with oral anticoagulants: data from sicilian spontaneous reporting system database

OBJECTIVE

Direct oral anticoagulants (DOACs) were developed to avoid the limitations of vitamin K antagonists (VKAs). DOACs are associated with a greater incidence of gastrointestinal bleeding and a smaller number of intracranial haemorrhages than VKAs. Therefore, it is important to deepen our knowledge of their safety profiles. The aim of this study was thus to analyse adverse drug reaction (ADR) reports on DOACs and VKAs using the Sicilian Spontaneous Reporting System (SRS) database.

METHODS

All ADR reports with DOACs and VKAs as suspected drugs that were entered into the Sicilian SRS database during the period 2001-2019 were selected. In detail, all reports with the following single active substances were included: dabigatran etexilate, rivaroxaban, apixaban and edoxaban; acenocoumarol and warfarin were included as a comparator group. Descriptive statistical methodology was used to evaluate characteristics of the reported cases with a case-by-case assessment.

RESULTS AND DISCUSSION

Out of 521 reports related to anticoagulants, 444 (85.2%) and 77 (14.8%) involved DOACs and VKAs, respectively. DOAC-related reports were mainly of gastrointestinal disorders. In contrast, VKAs were mostly associated with blood and lymphatic system disorders, injury, investigations and vascular disorders. Many more cases of ADRs in the form of gastrointestinal disorders concerned dabigatran etexilate (n = 179, 73.7%) than the other DOACs, while ADRs in the form of blood disorders were mainly associated with acenocoumarol (n = 27, 57.4%). The most commonly reported Preferred Terms for DOACs were dyspepsia (n = 89, 17.1%), upper abdominal pain (n = 41, 9.2%) and pruritus (n = 26, 5.8%), whereas for VKAs, they were anaemia (n = 21, 27.3%) and hypocoagulable state (n = 18, 3.5%). Potentially interacting concomitant medications particularly included antithrombotic agents (n = 19, 4.3%) for DOACs and proton-pump inhibitors (PPIs) (n = 37, 48.1%) and antithrombotic agents (n = 13, 16.9%) for VKAs.

CONCLUSION

The ADRs most commonly associated with DOACs, especially dabigatran, were gastrointestinal disorders, particularly gastrointestinal bleeding. Our study also highlights the potential role of drug-drug interactions in the ADRs. The cases of gastrointestinal bleeding highlight the need for careful prescribing of DOACs and use of potentially interacting concomitant drugs.

Identifying and Characterizing Serious Adverse Drug Reactions Associated With Drug-Drug Interactions in a Spontaneous Reporting Database

Background: Drug-drug interactions (DDIs) are an important cause of adverse drug reactions (ADRs). In literature most of studies focus only on potential DDIs, while detailed data on serious ADRs associated with DDIs are limited. Our aim is to identify and characterize serious ADRs caused by DDIs using a spontaneous reporting database.

Methods: All serious ADR reports, not related to vaccines and with a “definite”, “probable” or “possible” causality assessment, inserted into the National Pharmacovigilance database from Veneto Region (January 1, 2015 to May 31, 2020) were analyzed. A list of drug pairs was created by selecting the reports containing at least two suspected or concomitant drugs. We verified which drug pairs potentially interacted according to the online version of DRUGDEX^® system. For each potential DDI we controlled whether the ADR description in the report corresponded to the interaction effect as described in Micromedex. A detailed characterization of all serious reports containing an occurring DDI was performed.

Results: In the study period a total of 31,604 reports of suspected ADRs from the Veneto Region were identified, of which 2,195 serious reports (6.9% of all ADR reports) containing at least two suspected or concomitant drugs were analyzed. We identified 1,208 ADR reports with at least one potential DDI (55.0% of 2,195) and 381 reports (17.4% of 2,195 reports) with an occurring ADR associated with a DDI. The median age of patients and the number of contraindicated or major DDIs were significantly higher in reports with an occurring DDI. Warfarin was the most frequently reported interacting drug and the most common ADRs were gastrointestinal or cerebral hemorrhagic events. The proton pump inhibitors/warfarin, followed by platelet aggregation inhibitors/warfarin were the drug-drug combinations most frequently involved in ADRs caused by DDIs. The highest proportion of fatal reports was observed with platelet aggregation inhibitors/warfarin and antidepressants/warfarin.

Conclusion: Our findings showed that about one-third of patients exposed to a potential DDI actually experienced a serious ADR. Furthermore, our study confirms that a spontaneous reporting database could be a valuable resource for identifying and characterizing ADRs caused by DDIs and the drugs leading to serious ADRs and deaths.

Non-vitamin K antagonist oral anticoagulants for stroke prevention in atrial fibrillation: safety issues in the elderly

INTRODUCTION

Non-vitamin K antagonist oral anticoagulants (NOACs) are increasingly used for stroke prevention in patients with atrial fibrillation (AF). Since NOACs are predominantly used in the elderly with AF at high risk for stroke and bleeding and with comorbidities requiring polypharmacy, it is important to assess their safety and efficacy in this population.

AREAS COVERED

We review changes in pharmacokinetics and pharmacodynamics observed with senescence and the effect on NOACs and drug and food interactions. We also provide an update on challenges related to NOAC use in situations that increases the risk for bleeding or require temporary discontinuation and address practical issues in the elderly AF patients managed on NOACs. Clinical studies and trials with cardiovascular outcomes reported from January 1990 to August 2020 were identified through the Medline database using PubMed, Cochrane Library, and EMBASE database.

EXPERT OPINION

NOACs are highly effective in preventing stroke in AF patients with non-inferior or superior efficacy to warfarin, with reduced risk of major bleeding. However, in the older-elderly, evidence comes mainly from observational studies or extrapolation from studies in populations with minimal functional limitations or comorbidities. The high upfront cost and out-of-pocket expense for copayment or deductibles also limit the use of this effective therapy in a substantial number of patients. The cost reduction may further improve long-term use for NOACs in stroke prevention in elderly patients with AF.

Comorbid depression in medical diseases

Depression is one of the most common comorbidities of many chronic medical diseases including cancer and cardiovascular, metabolic, inflammatory and neurological disorders. Indeed, the prevalence of depression in these patient groups is often substantially higher than in the general population, and depression accounts for a substantial part of the psychosocial burden of these disorders. Many factors can contribute to the occurrence of comorbid depression, such as shared genetic factors, converging biological pathways, social factors, health behaviours and psychological factors. Diagnosis of depression in patients with a medical disorder can be particularly challenging owing to symptomatic overlap. Although pharmacological and psychological treatments can be effective, adjustments may need to be made for patients with a comorbid medical disorder. In addition, symptoms or treatments of medical disorders may interfere with the treatment of depression. Conversely, symptoms of depression may decrease adherence to treatment of both disorders. Thus, comprehensive treatment plans are necessary to optimize care.