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496
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Introduction
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October 2013 - present
May 2011 - present
March 2010 - present
Publications
Publications (496)
Background and AimsThe burden of premature mortality due to opioid-related death has not been fully characterized. We calculated temporal trends in the proportion of deaths attributable to opioids and estimated years of potential life lost (YLL) due to opioid-related mortality in Ontario, Canada.DesignCross-sectional study.SettingOntario, Canada.Pa...
Opioids are widely prescribed for chronic nonmalignant pain, often at doses exceeding those recommended in clinical practice guidelines. However, the risk-benefit ratio of high-dose opioid therapy is not well characterized. The objective of this study was to characterize the relationship between opioid dose and opioid-related mortality.
We conducte...
Recent evidence suggests that, despite widespread use, self-monitoring of blood glucose levels has little clinical benefit in many patients with diabetes. The impact of more focused public-payer policies for the use of blood glucose test strips may be substantial.
We conducted a cross-sectional analysis of annual prescription claims for test strips...
Most proton pump inhibitors inhibit the bioactivation of clopidogrel to its active metabolite. The clinical significance of this drug interaction is unknown.
We conducted a population-based nested case-control study among patients aged 66 years or older who commenced clopidogrel between Apr. 1, 2002, and Dec. 31, 2007, following hospital discharge...
To compare the risk of acute myocardial infarction, heart failure, and death in patients with type 2 diabetes treated with rosiglitazone and pioglitazone.
Retrospective cohort study.
Ontario, Canada.
Outpatients aged 66 years and older who were started on rosiglitazone or pioglitazone between 1 April 2002 and 31 March 2008.
Composite of death or ho...
Background
The burden of hepatitis C virus (HCV)-related hospitalizations is substantial, particularly among people with HIV and HCV (HIV/HCV). In Ontario, Canada, use of direct-acting antivirals (DAAs) increased following policies removing fibrosis stage restrictions and the approval of pan-genotypic agents in 2017 and 2018, respectively. We exami...
Introduction: Concerns have been raised that glucagon-like peptide 1 receptor agonists (GLP1-RAs) may increase the risk of thyroid cancer, but evidence remains conflicting. We therefore investigated if GLP1-RA use, compared with use of dipeptidyl peptidase-4 inhibitors (DPP-4is), was associated with thyroid cancer risk in patients with type 2 diabe...
Executive Summary: Omalizumab is recommended for the treatment of patients with moderate to severe chronic idiopathic urticaria (CIU) when their symptoms do not respond to nonsedating H 1 antihistamines. Omalizumab is being used for long-term treatment of CIU, but there is limited evidence regarding its chronic use beyond 24 weeks. A Drug Utilizati...
What Is the issue? Data on trends in the pharmaceutical market remain limited. We offer an annual update on estimated drug purchases in Canada and highlight key factors that could impact future spending. What Did We do? We conducted a retrospective time-series analysis of annual estimated drug purchases across Canada between 2001 and 2023 using IQV...
Objective
Electroconvulsive therapy (ECT) is an evidence-based treatment for schizophrenia when anti-psychotic medications do not sufficiently control symptoms of psychosis or rapid response is required. Little is known about how it is used in routine clinical practice. The aim of this study was to identify the association of demographic and clinic...
Objective
We aimed to measure the change in proportion of opioid-related overdose deaths attributed to people experiencing homelessness and to compare the opioid-related fatalities between individuals experiencing homelessness and not experiencing homelessness at time of death. ApproachWe conducted a population-based, time-trend analysis using coro...
Objective
Health administrative data can support population-level research among people who inject drugs (PWID), however these data sources remain underutilized due to the difficulty in identifying drug use in routinely collected data. We validated case-ascertainment algorithms to identify PWID and tested their application in a hepatitis C (HCV) co...
Objectives
To examine trends in pregnancy-associated non-fatal and fatal opioid toxicity and all-cause mortality, and identify associated factors. ApproachWe conducted a population-based study of 1,555,370 pregnancies in Ontario, Canada, 2013-2022. We analyzed linked administrative datasets, including coroner data, and calculated pregnancy-associat...
Importance
Serious cutaneous adverse drug reactions (cADRs) are potentially life-threatening drug hypersensitivity reactions involving the skin and internal organs. Antibiotics are a recognized cause of these reactions, but no studies have compared relative risks across antibiotic classes.
Objectives
To explore the risk of serious cADRs associated...
The COVID-19 pandemic was associated with increases in the prevalence of depression and anxiety among children and young adults. We studied whether the pandemic was associated with changes in prescription benzodiazepine use. We conducted a population-based study of benzodiazepine dispensing to children and young adults ≤ 24 years old between Januar...
Objectives
To evaluate whether providing family physicians with feedback on their antibiotic prescribing compared with that of their peers reduces antibiotic prescriptions. To also identify effects on antibiotic prescribing from case-mix adjusted feedback reports and messages emphasising antibiotic associated harms.
Design
Pragmatic, factorial ran...
Background:
People with opioid use disorder (OUD) are at risk of premature death and can benefit from palliative care. We sought to compare palliative care provision for decedents with and without OUD.
Methods:
We conducted a cohort study using health administrative databases in Ontario, Canada, to identify people who died between July 1, 2015,...
Background
Alpha‐1 receptor antagonists may interfere with IL‐6 signaling and could therefore be a potential treatment for COVID‐19. However, the effectiveness of these drugs in mitigating the risk of clinical deterioration among non‐hospitalized patients with COVID‐19 is unknown.
Objectives
The aim of this study is to examine the association betw...
Background and aims
Identifying effective opioid treatment options during pregnancy is a high priority due to the growing prevalence of opioid use disorder across North America. We assessed the temporal impact of three population‐level interventions on the use of opioid agonist treatment (OAT) during pregnancy in Ontario, Canada.
Design
This was a...
Introduction
The North American toxic drug crisis has been framed as an epidemic primarily affecting white people. However, evidence suggests that deaths are rising among racialised people. Accordingly, we sought to describe and compare characteristics and circumstances of opioid toxicity deaths across ethno-racial groups.
Methods
We conducted a p...
( BMJ. 2023;380:e074005)
The use of opioids for pain relief following delivery is common; however, there is increasing concern that opioids are being passed to infants in large quantities during breastfeeding. This study aimed to determine if maternal postpartum use of opioids is associated with long-term side effects and complications in breastfee...
Aims
Naltrexone is recommended first-line to manage alcohol use disorder (AUD). With previous studies indicating poor retention on naltrexone, we determined duration of naltrexone use and assessed the association between prescription setting and time to discontinuation in Ontario.
Methods
We conducted a retrospective population-based cohort study...
Objective
The aim of this study was to compare time on treatment among individuals initiating buprenorphine/naloxone and methadone and understand how retention varies according to age, sex, and urban/rural residence.
Methods
We conducted a population-based retrospective cohort study among individuals aged 18 years and older, residing in Southern O...
Canada is experiencing an ongoing overdose crisis, driven by a toxic unregulated drug supply. Integrated safer supply pilot programs offer pharmaceutical alternatives, coupled with comprehensive support services, to individuals using unregulated drug supply who are at high risk of overdose. We collected data from December 2020 to January 2023 on cl...
Aims
Calls to prescribe safer supply hydromorphone (SSHM) as an alternative to the toxic drug supply increased during the COVID-19 pandemic but it is unknown whether prescribing behaviour was altered. We aimed to evaluate how the number of new SSHM dispensations changed during the pandemic in Ontario.
Methods
We conducted a retrospective interrupt...
Background:
Emergency department visits and hospital admissions for opioid toxicity are opportunities to initiate opioid agonist therapy (OAT), which reduces morbidity and mortality in patients with opioid use disorder (OUD). The study objectives were to evaluate OAT initiation rates after a hospital encounter for opioid toxicity in Ontario, Canad...
Background
The COVID-19 pandemic was associated with increases in the prevalence of depression, anxiety and behavioural problems among children and youth. Less well understood is the influence of the pandemic on antidepressant and antipsychotic use among children. This is important, as it is possible that antidepressants and antipsychotics were use...
Background
Substance use in pregnancy raises concern given its potential teratogenic effects. Given the unique needs of parenting people and the potential impact for developing children, specialized substance use treatment programs are increasingly being implemented for this population. Substance use treatment is associated with more positive neona...
OBJECTIVE
To examine factors associated with new persistent opioid use after childbirth.
METHODS
We conducted a population-based cohort study of individuals who initiated opioid therapy within 7 days of discharge from hospital after delivery between September 1, 2013, and September 30, 2021. The primary outcome was new persistent opioid use , whic...
Multidisciplinary chronic pain management includes pharmacologic, psychological, and interventional strategies. In Canada, the use of interventional pain blocks (PBs) has increased in recent years. We sought to determine the distribution and clustering of PBs among physicians in Ontario, and to examine differences in the patient and physician chara...
Background
To inform preparedness and population health action, we need to understand the effects of COVID-19 on health inequities. In this study, we assess the impact of COVID-19 on opioid toxicity deaths among people who experience incarceration compared to others in the general population in Ontario, Canada.
Methods
We conducted a retrospective...
Background
In January 2018, the Government of Ontario, Canada, initiated a universal pharmacare program (OHIP+) for all individuals aged 24 years and younger. In April 2019, the program was amended to cover only children and youth without private insurance. Because benzodiazepines are commonly prescribed to children and youth despite their potentia...
Aims:
To measure the change in proportion of opioid-related overdose deaths attributed to people experiencing homelessness and to compare the opioid-related fatalities between individuals experiencing homelessness and not experiencing homelessness at time of death.
Design, setting and participants:
Population-based, time-trend analysis using cor...
Background
In February 2018, Canada’s National Advisory Committee on Immunization (NACI) recommended antenatal tetanus–diphtheria–acellular pertussis (Tdap) immunization in every pregnancy regardless of previous Tdap immunization history. We examined the impact of the NACI recommendation on rates of infant pertussis in Ontario, Canada.
Methods
We...
Objectives:
People living with diabetes and not using insulin may not derive clinically significant benefit from routine glucose self-monitoring. As a result, in 2015 British Columbia (BC) introduced quantity restrictions for blood glucose test strips (BGTS) coverage in public plans. We studied the impact of this policy on utilization, costs, and...
Background:
Canada is experiencing an unprecedented drug toxicity crisis driven by a highly toxic unregulated drug supply contaminated with fentanyl, benzodiazepine, and other drugs. Safer supply pilot programs provide prescribed doses of pharmaceutical alternatives to individuals accessing the unregulated drug supply and have been implemented to...
Background
Hepatitis C virus (HCV) has high global prevalence and can lead to liver complications and death. Access to direct-acting antivirals (DAAs) in Canada increased following several policy changes, however the real-world impact of expanded DAA access and increased use of these drugs is unknown.
Objective
We aimed to determine the early chan...
Background:
Oxycodone is increasingly prescribed for postpartum analgesia in lieu of codeine owing to concerns regarding the neonatal safety of codeine during lactation. We examined whether initiation of oxycodone after delivery was associated with an increased risk of persistent opioid use relative to initiation of codeine.
Methods:
We conducte...
Background:
Slow-release oral morphine (SROM) is used to manage pain, and as opioid agonist treatment (OAT). Between 2017 and 2021 in Canada, several drug shortages occurred for Kadian© (SROM-24). The purpose of this study was to evaluate the impact of these shortages on people's ability to remain on this medication.
Methods:
We conducted a retr...
Importance:
Data suggest that the opioid crisis in North America has recently been reflected in opioid-related mortality among youths. Despite recommendation for its use, youths encounter barriers to accessing OAT, including stigma, burden of witnessed dosing, and lack of availability of youth-oriented services and prescribers comfortable treating...
Importance:
Opioid-related harms constitute a major public health crisis in the US, and this crisis has worsened during the COVID-19 pandemic.
Objectives:
To characterize the societal burden of unintentional opioid-related deaths in the US and describe changing mortality patterns during the COVID-19 pandemic.
Design, setting, and participants:...
Objectives
Despite the widespread use of prescription benzodiazepines, there are few studies examining trends and patterns of benzodiazepine-related toxicity. We describe the epidemiology of benzodiazepine-related toxicity in Ontario, Canada.
Methods
We conducted a population-based, cross-sectional study of Ontario residents who had an emergency d...
Objectives
To quantify well-child visits by age 2 years and developmental screening at the 18-month enhanced well-child visit among children with prenatal opioid exposure (POE) and to identify factors associated with study outcomes.
Design
Population-based cohort study.
Setting
Ontario, Canada.
Participants
22 276 children with POE born 2014–201...
Background
Hepatitis C is curable with direct-acting antivirals (DAAs). However, treatment uptake remains low among marginalized populations such as people who inject drugs. We sought to understand challenges to treatment uptake with DAAs among people living with hepatitis C and compare treatment experiences between people who do and do not inject...
BACKGROUND
Electronic prescribing (e-prescribing) is an approach designed to assist in facilitating safe and appropriate prescriptions for patients. Currently, it is unknown to what extent e-prescribing can influence the use of opioids and their specific clinical outcomes. To address this gap, a rapid scoping review was conducted.
OBJECTIVE
The ob...
Background
e-Prescribing is designed to assist in facilitating safe and appropriate prescriptions for patients. Currently, it is unknown to what extent e-prescribing for opioids influences experiences and outcomes. To address this gap, a rapid scoping review was conducted.
Objective
This rapid scoping review aims to (1) explore how e-prescribing h...
Background
In 2011, the Canadian Alliance for Monitoring Effectiveness and Safety of Antipsychotics in Children (CAMESA) published guidelines for the metabolic monitoring of antipsychotic-treated children and youth. Population-based studies examining adherence to these guidelines are needed to ensure the safe use of antipsychotics in children and y...
Objectives
To describe mortality due to opioid toxicity among people who experienced incarceration in Ontario between 2015 and 2020, during the fentanyl-dominant era.
Design
In this retrospective cohort study, we linked Ontario coronial data on opioid toxicity deaths between 2015 and 2020 with correctional data for adults incarcerated in Ontario p...
Importance:
Few interventions are proven to reduce total health care costs, and addressing cost-related nonadherence has the potential to do so.
Objective:
To determine the effect of eliminating out-of-pocket medication fees on total health care costs.
Design, setting, and participants:
This secondary analysis of a multicenter randomized clini...
Objective:
Stimulants are first-line pharmacotherapy for individuals with attention-deficit hyperactivity disorder. However, disparities in drug coverage may contribute to inequitable treatment access. In January 2018, the government of Ontario, Canada, implemented a publicly-funded program (OHIP+) providing universal access to medications at no c...
Objective
To examine whether maternal opioid treatment after delivery is associated with an increased risk of adverse infant outcomes.
Design
Population based cohort study.
Setting
Ontario, Canada.
Participants
865 691 mother-infant pairs discharged from hospital alive within seven days of delivery from 1 September 2012 to 31 March 2020. Each mo...
Background:
A randomized controlled trial involving a high-risk, unvaccinated population that was conducted before the Omicron variant emerged found that nirmatrelvir-ritonavir was effective in preventing progression to severe COVID-19. Our objective was to evaluate the effectiveness of nirmatrelvir-ritonavir in preventing severe COVID-19 while Om...
Background
Population-based research examining geographic variability in psychotropic medication dispensing to children and youth and the sociodemographic correlates of such variation is lacking. Variation in psychotropic use could reflect disparities in access to non-pharmacologic interventions and identify potentially concerning use patterns.
Me...
Background
Long-term opioid use is an increasingly important problem related to the ongoing opioid epidemic. The purpose of this study was to identify patient, hospitalization and system-level determinants of long term opioid therapy (LTOT) among patients recently discharged from hospital.
Design
To be eligible for this study, patient needed to ha...
Introduction
The recent publication of a national guideline and quality standards in Canada have provided clinicians with new, evidence-based recommendations on safe, appropriate opioid use. We sought to characterize how well opioid initiation practices aligned with these recommendations before and following their release.
Methods
We conducted a p...
Objective:
Recent Canadian data shows that the prescribing of opioids has declined while the number of opioid deaths continue to rise. This study aimed to assess the relationship between neighbourhood-level opioid prescription rates and opioid-related mortality amongst individuals without an opioid prescription.
Methods:
This was a nested case-c...
Background
The mandated reporting of medication-related errors in community pharmacies including incidents resulting in inappropriate medication use and near misses intercepted before reaching the patient can be utilized as learning opportunities to aid in the prevention of future events.
Objectives
To examine reporting uptake, trends, and initial...
Purpose:
The management of chronic pain often involves interventional procedures such as injections. Nevertheless, there have been concerns raised regarding the frequency with which these injections are being performed. We conducted a descriptive study to examine trends in the use of pain injections over a ten-year time period in Ontario, Canada....
In 2021, our group presented the first forecast of trends in the Canadian pharmaceutical market. The goal was to identify factors that may influence future spending to support public and private decision-makers in predicting the growth of national drug purchases. This report is the first annual update of estimated pharmaceutical drug purchases in C...
Background
Individuals with intellectual and developmental disability (IDD) can have a high prevalence of pain, which can be managed with prescription opioids. However, the prevalence of substance use disorder is also high in this population, raising concern about opioid-related adverse events.
Aims
To assess the risk of opioid-related adverse eve...
Background:
Hydroxychloroquine and ivermectin received widespread attention after initial studies suggested that they were effective against COVID-19. However, several of these studies were later discredited.
Objectives:
We explored the impact of scientific articles, public announcements and social media posts on hydroxychloroquine and ivermecti...
Background: Our objective was to evaluate the real world effectiveness of nirmatrelvir/ritonavir to prevent severe COVID-19 while Omicron and its subvariants predominate.
Methods: We conducted a population based cohort study in Ontario, Canada including all residents >17 years of age who tested positive for SARS-CoV-2 by PCR between 4 April and 31...
Background
Acamprosate and naltrexone, evidence-based pharmacotherapies for alcohol use disorder (AUD), are publicly covered by the Ontario Drug Benefit (ODB) programs; however, their availability has changed over time, with expanded formulary access in July 2018, followed by an acamprosate shortage in February 2019 and ending in July 2020. We eval...