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result(s) for
"Denus, Simon"
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Spironolactone Metabolites in TOPCAT — New Insights into Regional Variation
by
Pfeffer, Marc A
,
Desai, Akshay S
,
Lavoie, Joël
in
Canada
,
Canrenone - blood
,
Clinical Trials as Topic
2017
In a subgroup of TOPCAT participants assigned to spironolactone, the spironolactone metabolite canrenone was measured to assess adherence. Canrenone levels were undetectable in 30% of participants from Russia, as compared with only 3% from the United States and Canada.
To the Editor:
In the Treatment of Preserved Cardiac Function Heart Failure with an Aldosterone Antagonist (TOPCAT) trial, patients with heart failure and preserved ejection fraction were randomly assigned to receive either spironolactone or placebo. The investigators found that the incidence of the primary composite end point of death from cardiovascular causes, hospitalization for heart failure, or resuscitated cardiac arrest was not significantly lower in the spironolactone group than in the placebo group, but the incidence of hospitalization for heart failure was significantly lower in the spironolactone group.
1
However, significant differences in the clinical profiles, event rates, and responses to . . .
Journal Article
Construction of a femininity score in the UK Biobank and its association with angina diagnosis prior to myocardial infarction
2022
Gender captures social components beyond biological sex and can add valuable insight to health studies in populations. However, assessment of gender typically relies on questionnaires which may not be available. The aim of this study is to construct a gender metric using available variables in the UK Biobank and to apply it to the study of angina diagnosis. Proxy variables for femininity characteristics were identified in the UK Biobank and regressed on sex to construct a composite femininity score (FS) validated using tenfold cross-validation. The FS was assessed as a predictor of angina diagnosis before incident myocardial infarction (MI) events. The FS was derived for 315,937 UK Biobank participants. In 3059 individuals with no history of MI at study entry who had an incident MI event, the FS was a significant predictor of angina diagnosis prior to MI (OR 1.24, 95% CI 1.10–1.39, P < 0.001) with a significant sex-by-FS interaction effect (P = 0.003). The FS was positively associated with angina diagnosis prior to MI in men (OR 1.37, 95% CI 1.19–1.57, P < 0.001), but not in women. We have provided a new tool to conduct gender-sensitive analyses in observational studies, and applied it to study of angina diagnosis prior to MI.
Journal Article
An association study of ABCG2 rs2231142 on the concentrations of allopurinol and its metabolites
by
St‐Jean, Isabelle
,
Denus, Simon
,
Gaulin, Marie‐Josée
in
ABCG2 gene
,
Allopurinol
,
Allopurinol - analogs & derivatives
2022
ABCG2 is a gene that codes for the human breast cancer resistance protein (BCRP). It is established that rs2231142 G>T, a single nucleotide polymorphism of the ABCG2 gene, is associated with gout and poor response to allopurinol, a uric acid‐lowering agent used to treat this condition. It has also been suggested that oxypurinol, the primary active metabolite of allopurinol, is a substrate of the BCRP. We thus hypothesized that carrying the rs2231142 variant would be associated with decreased oxypurinol concentrations, which would explain the lower reduction in uric acid. We performed a cross‐sectional study to investigate the association between the ABCG2 rs2231142 variant and oxypurinol, allopurinol, and allopurinol riboside concentrations in 459 participants from the Montreal Heart Institute Hospital Cohort. Age, sex, weight, use of diuretics, and estimated glomerular filtration rate were all significantly associated with oxypurinol plasma concentration. No association was found between rs2231142 and oxypurinol, allopurinol and allopurinol riboside plasma concentrations. Rs2231142 was not significantly associated with daily allopurinol dose in the overall population, but an association was observed in men, with T carriers receiving higher doses. Our results do not support a major role of ABCG2 in the pharmacokinetics of allopurinol or its metabolites. The underlying mechanism of the association between rs2231142 and allopurinol efficacy requires further investigation.
Journal Article
Sex, Drugs, and Heart Failure: A Sex-Sensitive Review of the Evidence Base Behind Current Heart Failure Clinical Guidelines
by
Levinsson, Anna
,
de Denus, Simon
,
Dubé, Marie-Pierre
in
Cardiac arrhythmia
,
Cardiovascular Agents - therapeutic use
,
Cardiovascular disease
2018
Abstract
Heart failure (HF) is a complex disease, almost as common in women as in men. Nonetheless, HF clinical presentation, prognosis, and aetiology vary by sex. This review summarizes the current state of sex-sensitive issues related to HF drugs included in treatment guidelines and suggests future directions for improved care. Heart failure presentation differs between female and male patients: females more often show with hypertensive aetiology and the preserved ejection fraction phenotype, while men more often show ischaemic aetiology and the reduced ejection fraction phenotype. Yet the HF clinical guidelines in Europe, the United States, and Canada do not reflect the sexual dimorphism. Further, in randomized clinical trials of HF medication, women are largely underrepresented, typically consisting of ≥70% men. Given the knowledge that some adverse drug reactions, such as torsade de pointes and angiotensin-converting enzyme inhibitor-induced cough, occur more frequently in women, we emphasize the need to test medications thoroughly in both sexes and explore sexual dimorphisms. To better represent all of the targeted patient population and provide better care for all, two kinds of change must come about: recruitment methods to randomized clinical trial samples need to evolve and the participation needs to seem more attractive to women.
Journal Article
Comparative Effectiveness and Safety of Low-Dose Oral Anticoagulants in Patients With Atrial Fibrillation
by
Dragomir, Alice
,
Perreault, Sylvie
,
Tardif, Jean-Claude
in
Anticoagulants
,
atrial fibrillation
,
Cardiac arrhythmia
2022
Aims: Observational studies of various dose levels of direct oral anticoagulants (DOACs) for patients with atrial fibrillation (AF) found that a high proportion of patients received a dose lower than the target dose tested in randomized controlled trials. There is a need to compare low-dose DOACs with warfarin or other DOACs on effectiveness and safety. Methods: Using administrative data from Quebec province, Canada, we built a cohort of new warfarin or DOAC users discharged from hospital between 2011 and 2017. We determined CHA 2 DS 2 -VASc and HAS-BLED scores, and comorbidities for 3-year prior cohort entry. The primary effectiveness endpoint was a composite of ischemic stroke/systemic embolism (SE), and secondary outcomes included a safety composite of major bleeding (MB) events and effectiveness composite (stroke/SE, death) at 1-year follow-up. We contrasted each low-dose DOAC with warfarin or other DOACs as references using inverse probability of treatment weighting to estimate marginal Cox hazard ratios (HRs). Results: The cohort comprised 22,969 patients (mean age: 80–86). We did not find a significant risk reduction for the stroke/SE primary effectiveness endpoint for DOACs vs. warfarin; however, we observed a significantly lower risk for low-dose dabigatran vs. warfarin (HR [95%CI]: 0.59 [0.42–0.81]) for effectiveness composite, mainly due to a lower death rate. The differences in effectiveness and safety composites between low-dose rivaroxaban vs. warfarin were not significant. However, low-dose apixaban had a better safety composite (HR: 0.68 [0.53–0.88]) vs. warfarin. Comparisons of dabigatran vs. apixaban showed a lower risk of stroke/SE (HR: 0.53 [0.30–0.93]) and a 2-fold higher risk of MB. The MB risk was higher for rivaroxaban than for apixaban (HR: 1.58 [1.09–2.29]). Conclusions: The results of this population-based study suggest that low-dose dabigatran has a better effective composite than warfarin. Compared with apixaban, low-dose dabigatran had a better effectiveness composite but a worse safety profile. Low-dose apixaban had a better safety composite than warfarin and other low-dose DOACs. Given that the comparative effectiveness and safety seem to vary from one DOAC to another, pharmacokinetic data for specific populations are now warranted.
Journal Article
Leveraging large observational studies to discover genetic determinants of drug concentrations: A proof‐of‐concept study
by
Denus, Simon
,
Gaulin, Marie‐Josée
,
Meloche, Maxime
in
Biobanks
,
Cardiac arrhythmia
,
Consortia
2022
Large, observational genetic studies are commonly used to identify genetic factors associated with diseases and disease‐related traits. Such cohorts have not been commonly used to identify genetic predictors of drug dosing or concentrations, perhaps because of the heterogeneity in drug dosing and formulation, and the random timing of blood sampling. We hypothesized that large sample sizes relative to traditional pharmacokinetic studies would compensate for this variability and enable the identification of pharmacogenetic predictors of drug concentrations. We performed a cross‐sectional, proof‐of‐concept association study to replicate the well‐established association between metoprolol concentrations and CYP2D6 genotype‐inferred metabolizer phenotypes in participants from the Montreal Heart Institute Hospital Cohort undergoing metoprolol therapy. Plasma concentrations of metoprolol and α‐hydroxymetoprolol (α‐OH‐metoprolol) were measured in samples collected randomly regarding the previous metoprolol dose. A total of 999 individuals were included. The metoprolol daily dose ranged from 6.25 to 400 mg (mean 84.3 ± 57.1 mg). CYP2D6‐inferred phenotype was significantly associated with both metoprolol and α‐OH‐metoprolol in unadjusted and adjusted models (all p < 10−14). Models for metoprolol daily dose showed consistent results. Our study suggests that randomly drawn blood samples from biobanks can serve as a new approach to discover genetic associations related to drug concentrations and dosing, with potentially broader implications for genomewide association studies on the pharmacogenomics of drug metabolism.
Journal Article
Impact of diabetes on serum biomarkers in heart failure with preserved ejection fraction: insights from the TOPCAT trial
2021
Aims Diabetes mellitus (DM) is common in heart failure with preserved ejection fraction (HFpEF). Patients with DM and heart failure with reduced ejection fraction have higher levels of cardiac, profibrotic, and proinflammatory biomarkers relative to non‐diabetics. Limited data are available regarding the biomarker profiles of HFpEF patients with diabetes (DM) vs. no diabetes (non‐DM) and the impact of spironolactone on these biomarkers. This study aims to address such gaps in the literature. Methods and results Biomarkers were measured at randomization and at 12 months in 248 patients enrolled in Treatment of Preserved Cardiac Function Heart Failure with an Aldosterone Antagonist's North American cohort. At baseline, DM patients had significantly lower estimated glomerular filtration rate and higher high‐sensitivity C‐reactive protein, pro‐collagen type III amino‐terminal peptide, tissue inhibitor of metalloproteinase 1 (TIMP‐1), and galectin‐3 levels than those without diabetes. There was a significantly larger 12 month increase in levels of high‐sensitivity troponin T (hs‐TnT), a marker of myocyte death, in DM patients. Elevated pro‐collagen type III amino‐terminal peptide and galectin‐3 levels were associated with an increased risk of the primary outcome (cardiovascular mortality, aborted cardiac arrest, or heart failure hospitalization) in DM patients, but not in those without diabetes. A statistically significant interaction between spironolactone and diabetes status was observed for hs‐TnT and for TIMP‐1, with greater biomarker reductions among those with diabetes treated with spironolactone. Conclusions The presence of diabetes is associated with higher levels of cardiac, profibrotic, and proinflammatory biomarkers in HFpEF. Spironolactone appears to alter the determinants of extracellular matrix remodelling in an anti‐fibrotic fashion in patients with diabetes, reflected by changes in hs‐TnT and TIMP‐1 levels over time.
Journal Article
A Meta-Analysis of the Effect of Paper Versus Digital Reading on Reading Comprehension in Health Professional Education
by
Lapierre, Alexandra
,
Fontaine, Guillaume
,
Denus, Simon de
in
Bias
,
Comparative analysis
,
Comprehension
2021
Objective. Despite a rise in the use of digital education in health professional education (HPE), little is known about the comparative effectiveness of paper-based reading and its digital alternative on reading comprehension. The objectives of this study were to identify, appraise, and synthesize the evidence regarding the effect of how media is read on reading comprehension in the context of HPE.
Methods. Observational, quasi-experimental, and experimental studies published before April 16, 2021, were included if they compared the effectiveness of paper-based vs digital-based reading on reading comprehension among HPE students, trainees, and residents. Random-effects meta-analyses were performed using standardized mean differences.
Results. From a pool of 2,208 references, we identified and included 10 controlled studies that had collectively enrolled 817 participants. Meta-analyses revealed a slight but nonsignificant advantage to students reading paper-based HPE texts rather than digital text (standardized mean difference, -0.08; 95% CI -0.28 to 0.12). Subgroup analyses revealed that students reading HPE-related texts had better reading comprehension when reading text on paper rather than digitally (SMD = -0.36; 95% CI -0.69 to -0.03). Heterogeneity was low in all analyses. The quality of evidence was low because of risks of bias across studies.
Summary. Current evidence suggests little to no difference in students’ comprehension when reading HPE texts on paper vs digitally. However, we observed effects favoring reading paper-based texts when texts relevant to the students’ professional discipline were considered. Rigorous studies are needed to confirm this finding and to evaluate new means of boosting reading comprehension among students in HPE programs.
Journal Article
Females present higher dose‐adjusted drug concentrations of metoprolol and allopurinol/oxypurinol than males
2023
Females present a higher risk of adverse drug reactions. Sex‐related differences in drug concentrations may contribute to these observations but they remain understudied given the underrepresentation of females in clinical trials. The aim of this study was to investigate whether anthropometric and socioeconomic factors and comorbidities could explain sex‐related differences in concentrations and dosing for metoprolol and oxypurinol, the active metabolite of allopurinol. We conducted an analysis of two cross‐sectional studies. Participants were self‐described “White” adults taking metoprolol or allopurinol selected from the Montreal Heart Institute Hospital Cohort. A total of 1007 participants were included in the metoprolol subpopulation and 459 participants in the allopurinol subpopulation; 73% and 86% of the participants from the metoprolol and allopurinol subpopulations were males, respectively. Females presented higher age‐ and dose‐adjusted concentrations of both metoprolol and oxypurinol (both p < 0.03). Accordingly, females presented higher unadjusted and age‐adjusted concentration:dose ratio of both metoprolol and allopurinol/oxypurinol compared to males (all p < 3.0 × 10−4). Sex remained an independent predictor of metoprolol concentrations (p < 0.01), but not of oxypurinol concentrations, after adjusting for other predictors. In addition to sex, age, daily dose, use of moderate to strong CYP2D6 inhibitors, weight, and CYP2D6 genotype‐inferred phenotype were associated with concentrations of metoprolol (all p < 0.01). Daily dose, weight, estimated glomerular filtration rate (eGFR), and employment status were associated with oxypurinol concentrations (all p < 0.01). Females present higher dose‐adjusted concentrations of metoprolol and oxypurinol than males. This suggests the need for sex‐specific dosing requirements for these drugs, although this hypothesis should be validated in prospective studies.
Journal Article
Impact of amiodarone use on metoprolol concentrations, α‐OH ‐metoprolol concentrations, metoprolol dosing and heart rate: A cross‐sectional study
by
Gaulin, Marie‐Josée
,
Meloche, Maxime
,
Robert, Sabrina
in
amiodarone
,
Cardiac arrhythmia
,
Chi-square test
2023
Small studies suggest that amiodarone is a weak inhibitor of cytochrome P450 (CYP) 2D6. Inhibition of CYP2D6 leads to increases in concentrations of drugs metabolized by the enzyme, such as metoprolol. Considering that both metoprolol and amiodarone have β‐adrenergic blocking properties and that the modest interaction between the two drugs would result in increased metoprolol concentrations, this could lead to a higher risk of bradycardia and atrioventricular block. The primary objective of this study was to evaluate whether metoprolol plasma concentrations collected at random timepoints from patients enrolled in the Montreal Heart Institute Hospital Cohort could be useful in identifying the modest pharmacokinetic interaction between amiodarone and metoprolol. We performed an analysis of a cross‐sectional study, conducted as part of the Montreal Heart Institute Hospital Cohort. All participants were self‐described “White” adults with metoprolol being a part of their daily pharmacotherapy regimen. Of the 999 patients being treated with metoprolol, 36 were also taking amiodarone. Amiodarone use was associated with higher metoprolol concentrations following adjustment for different covariates ( p = .0132). Consistently, the association between amiodarone use and lower heart rate was apparent and significant after adjustment for all covariates under study ( p = .0001). Our results highlight that single randomly collected blood samples can be leveraged to detect modest pharmacokinetic interactions.
Journal Article