A Cost-Effectiveness Analysis of Biomarkers for Risk Prediction in Atrial Fibrillation.

Rationale: Atrial fibrillation (AF) is associated with an increased risk of thromboembolism. This risk is currently assessed with scoring systems based on clinical characteristics. However, these tools have limited prognostic performance.

Trajectories of systemic agent use and associated depression- and anxiety-related health care costs among patients with psoriasis.

Background: Systemic treatment patterns and related mental health disorders and economic burden among patients with psoriasis are largely unknown.

Objective: To assess systemic treatment patterns and associated depression and anxiety-related health care costs among patients with psoriasis initiating a conventional systemic treatment (CST).

Methods: Using a retrospective cohort design with sequence and cluster analyses, we assessed systemic treatment trajectories (CST and tumor necrosis factor inhibitors or ustekinumab, [TNFi/UST]) over a 2-year period following CST initiation.

Sex Differences in the Patterns of Systemic Agent use Among Patients With Psoriasis: A Retrospective Cohort Study in Quebec, Canada.

Sex differences exist in psoriasis manifestation and expectations from treatment with systemic agents, including, conventional systemic agents (CSA) and tumor necrosis factor inhibitors or ustekinumab (TNFi/UST). However, sex differences in patterns of systemic agent use, such as CSA discontinuation and switch from CSA to TNFi/UST have not been examined. To assess sex differences in patterns of CSA use and identify factors associated with switch to (or add) a TNFi/UST and those associated with CSA discontinuation.

Domperidone increases harmful cardiac events in Parkinson's disease: A Bayesian re-analysis of an observational study.

Objectives: To assess the risks of ventricular tachyarrhythmia/sudden cardiac death (VT/SCD) with domperidone use in Parkinson's disease (PD).

Study Designs And Settings: Using Bayesian methods, results from an observationalstudy were combined with prior beliefs to calculate posterior probabilities of increasedrelative risk (RR)) of VT/SCD with use of domperidone compared to non-use and ofharm, defined as risk exceeding 15%. The analyses were carried with normallydistributed priors (log (RR)): uninformative (N(0,10)) or informative (N(0.

Cost-effectiveness of low-dose colchicine after myocardial infarction in the Colchicine Cardiovascular Outcomes Trial (COLCOT).

Aims: In the randomized, placebo-controlled Colchicine Cardiovascular Outcomes Trial (COLCOT) of 4745 patients enrolled within 30 days after myocardial infarction (MI), low-dose colchicine (0.5 mg once daily) reduced the incidence of the primary composite endpoint of cardiovascular death, resuscitated cardiac arrest, MI, stroke, or urgent hospitalization for angina leading to coronary revascularization. To assess the in-trial period and lifetime cost-effectiveness of low-dose colchicine therapy compared to placebo in post-MI patients on standard-of-care therapy.

Pharmacologically pertinent period of effect (PPPE).

Background: The period of time during which a patient is exposed to a drug does not necessarily correspond to the period during which the drug produces the adverse effect under consideration. We propose the term Pharmacologically pertinent period of effect (PPPE) to address this time window. We explored the PPPE in light of the rofecoxib saga.

Value of a Hypothetical Pharmacogenomic Test for the Diagnosis of Statin-Induced Myopathy in Patients at High Cardiovascular Risk.

We recently conducted two economic evaluations of a hypothetical pharmacogenomic test for statin-induced myopathy (SIM) in patients at high cardiovascular risk. Although the models differed in modeling technique and data inputs, both yielded similar results. We believe our approach to assessing the economic value of a diagnostic test was highly advantageous as it characterized the complete range of false-negative and false-positive test outcomes.

Healthcare Utilization after Acute Kidney Injury in the Pediatric Intensive Care Unit.

Background And Objectives: Little is known about the long-term burden of AKI in the pediatric intensive care unit. We aim to evaluate if pediatric AKI is associated with higher health service use post-hospital discharge.

Design, Setting, Participants, & Measurements: This is a retrospective cohort study of children (≤18 years old) admitted to two tertiary centers in Montreal, Canada.

A Discrete Event Simulation Model to Assess the Economic Value of a Hypothetical Pharmacogenomics Test for Statin-Induced Myopathy in Patients Initiating a Statin in Secondary Cardiovascular Prevention.

Background: Statin (HMG-CoA reductase inhibitor) therapy is the mainstay dyslipidemia treatment and reduces the risk of a cardiovascular (CV) event (CVE) by up to 35%. However, adherence to statin therapy is poor. One reason patients discontinue statin therapy is musculoskeletal pain and the associated risk of rhabdomyolysis.

Rationale, design, and preliminary results of the Quebec Warfarin Cohort Study.

Over- and undercoagulation with warfarin are associated with hemorrhagic and thromboembolic events, respectively. Genetic and clinical factors affect warfarin response, and the causes of this variability remain unclear. We present descriptive statistics and test for predictors of poor anticoagulation control.

The impact of renal protection clinics on prescription of and adherence to cardioprotective drug therapy in chronic kidney disease patients.

The aim of this study was to assess the impact of follow-up in renal protection clinics on the prescription of and adherence to cardioprotective drugs in patients with chronic kidney disease (CKD). We studied stage 4 and 5 CKD patients who initiated follow-up in three renal protection clinics. The prescription pattern of antihypertensive agents (AHA) and lipid-lowering agents (LLAs) was measured as the percentage of patients who are prescribed the agents of interest at a given time.

Cost-Effectiveness Analysis of Fosfomycin for Treatment of Uncomplicated Urinary Tract Infections in Ontario.

. Bacterial resistance to antibiotics traditionally used to treat uncomplicated urinary tract infections (uUTIs) is rising in Canada. We compared the cost-per-patient in Ontario of including fosfomycin (an antibiotic with a low resistance profile) as an option for first-line empirical treatment of uUTIs with current cost of treatment with sulfonamides, fluoroquinolones, and nitrofurantoin.

Use of Continuous Exposure Variables when Examining Dose-Dependent Pharmacological Effects - Application to the Association between Exposure to Higher Statin Doses and the Incidence of Diabetes.

Background: Many observational studies have found an association between the exposure to statins and the increased risk of diabetes, mostly through the use of intent-to-treat (ITT) like exposure measure (EM). ITT like EM may not adequately reflect the mechanism of action by which statins could cause diabetes.

Objectives: To determine if continuous EMs can more accurately reflect the mechanism of action by which statins and incidence of diabetes would be associated than ITT like EM.

Economic Evaluation of a Pharmacogenomics Test for Statin-Induced Myopathy in Cardiovascular High-Risk Patients Initiating a Statin.

Background: Statins are the mainstay hypercholesterolemia treatment and reduce the risk of cardiovascular events in patients. However, statin therapy is often interrupted in patients experiencing musculoskeletal pain or myopathy, which are common in this patient group. Currently, the standard tests for diagnosing statin myopathies are difficult to interpret.

A model to assess the cost-effectiveness of pharmacogenomics tests in chronic heart failure: the case of ivabradine.

Pharmacogenomics (PGx) tests have the potential of improving the effectiveness of expensive new drugs by predicting the likelihood, for a particular patient, to respond to a treatment. The objective of this study was to develop a pharmacoeconomic model to determine the characteristics and the cost-effectiveness of a hypothetical PGx test, which would identify patients who are most likely to respond to an expensive treatment for chronic heart failure. For this purpose, we chose the example of ivabradine.

Maximal expected benefits from lowering cholesterol in primary prevention for a high-risk population.

Aims: The objective of this study was to estimate the maximal clinical benefit that could be reasonably expected from a cholesterol-lowering intervention.

Materials And Methods: We used a hypothetical population at high risk of cardiovascular disease events from three risk assessment models including the Framingham risk function, the Score Canada and the Pooled Cohort Risk Assessment Equations. Our source population were all 55-year-old smoking men with diabetes, hypertension and low HDL.

Performance of the high-dimensional propensity score in adjusting for unmeasured confounders.

Purpose: High-dimensional propensity scores (hdPS) can adjust for measured confounders, but it remains unclear how well it can adjust for unmeasured confounders. Our goal was to identify if the hdPS method could adjust for confounders which were hidden to the hdPS algorithm.

Method: The hdPS algorithm was used to estimate two hdPS; the first version (hdPS-1) was estimated using data provided by 6 data dimensions and the second version (hdPS-2) was estimated using data provided from only two of the 6 data dimensions.

Association Between Incretin-Based Drugs and the Risk of Acute Pancreatitis.

Importance: The association between incretin-based drugs, such as dipeptidyl peptidase 4 (DPP-4) inhibitors and glucagon-like peptide 1 (GLP-1) agonists, and acute pancreatitis is controversial.

Objective: To determine whether the use of incretin-based drugs, compared with the use of 2 or more other oral antidiabetic drugs, is associated with an increased risk of acute pancreatitis.

Design, Setting, And Participants: A large, international, multicenter, population-based cohort study was conducted using combined health records from 7 participating sites in Canada, the United States, and the United Kingdom.

The missing cause approach to unmeasured confounding in pharmacoepidemiology.

Unmeasured confounding is a major threat to the validity of pharmacoepidemiological studies of medication safety and effectiveness. We propose a new method for detecting and reducing the impact of unobserved confounding in large observational database studies. The method uses assumptions similar to the prescribing preference-based instrumental variable (IV) approach.

Head to head comparison of the propensity score and the high-dimensional propensity score matching methods.

Background: Comparative performance of the traditional propensity score (PS) and high-dimensional propensity score (hdPS) methods in the adjustment for confounding by indication remains unclear. We aimed to identify which method provided the best adjustment for confounding by indication within the context of the risk of diabetes among patients exposed to moderate versus high potency statins.

Method: A cohort of diabetes-free incident statins users was identified from the Quebec's publicly funded medico-administrative database (Full Cohort).