Ontario Population Research Articles

Assessment of Age and Sex Differences in Risk of 1-Year Mortality After Emergency Department Visits Caused by Alcohol Use

This cross-sectional study assesses age and sex differences in risk of 1-year mortality in patients with emergency department visits due to alcohol compared with the general population in Ontario, Canada.

Vaccine Effectiveness Against SARS-CoV-2 Infection and Severe Outcomes in the Maintenance Dialysis Population in Ontario, Canada.

Vaccination studies in the hemodialysis population have demonstrated decreased antibody response compared with healthy controls, but vaccine effectiveness for preventing SARS-CoV-2 infection and severe disease is undetermined. We conducted a retrospective cohort study in the province of Ontario, Canada, between December 21, 2020, and June 30, 2021. Receipt of vaccine, SARS-CoV-2 infection, and related severe outcomes (hospitalization or death) were determined from provincial health administrative data. Receipt of one and two doses of vaccine were modeled in a time-varying cause-specific Cox proportional hazards model, adjusting for baseline characteristics, background community infection rates, and censoring for non-COVID death, recovered kidney function, transfer out of province, solid organ transplant, and withdrawal from dialysis. Among 13,759 individuals receiving maintenance dialysis, 2403 (17%) were unvaccinated and 11,356 (83%) had received at least one dose by June 30, 2021. Vaccine types were BNT162b2 (n=8455, 74%) and mRNA-1273 (n=2901, 26%); median time between the first and second dose was 36 days (IQR 28-51). The adjusted hazard ratio (HR) for SARS-CoV-2 infection and severe outcomes for one dose compared with unvaccinated was 0.59 (95% CI, 0.46 to 0.76) and 0.54 (95% CI, 0.37 to 0.77), respectively, and for two doses compared with unvaccinated was 0.31 (95% CI, 0.22 to 0.42) and 0.17 (95% CI, 0.1 to 0.3), respectively. There were no significant differences in vaccine effectiveness among age groups, dialysis modality, or vaccine type. COVID-19 vaccination is effective in the dialysis population to prevent SARS-CoV-2 infection and severe outcomes, despite concerns about suboptimal antibody responses.

COVID-19 vaccine coverage and factors associated with vaccine uptake among 23 247 adults with a recent history of homelessness in Ontario, Canada: a population-based cohort study

BackgroundPeople experiencing homelessness face a high risk of SARS-CoV-2 infection and transmission, as well as health complications and death due to COVID-19. Despite being prioritised for receiving the COVID-19 vaccine in many regions, little data are available on vaccine uptake in this vulnerable population. Using population-based health-care administrative data from Ontario, Canada—a region with a universal, publicly funded health system—we aimed to describe COVID-19 vaccine coverage (ie, the estimated percentage of people who have received a vaccine) and determinants of vaccine receipt among individuals with a recent history of homelessness.MethodsWe conducted a retrospective, population-based cohort study of adults (aged ≥18 years) with a recent experience of homelessness, inadequate housing, or shelter use as recorded in routinely collected health-care databases between June 14, 2020, and June 14, 2021 (a period within 6 months of Dec 14, 2020, when COVID-19 vaccine administration was initiated in Ontario). Participants were followed up from Dec 14, 2020, to Sept 30, 2021, for the receipt of one or two doses of a COVID-19 vaccine using the province's real-time centralised vaccine information system. We described COVID-19 vaccine coverage overall and within predefined subgroups. Using modified Poisson regression, we further identified sociodemographic factors, health-care usage, and clinical factors associated with receipt of at least one dose of a COVID-19 vaccine.Findings23 247 individuals with a recent history of homelessness were included in this study. Participants were predominantly male (14 752 [63·5%] of 23 247); nearly half were younger than 40 years (11 521 [49·6%]) and lived in large metropolitan regions (12 123 [52·2%]); and the majority (18 226 [78·4%]) visited a general practitioner for an in-person consultation during the observation period. By Sept 30, 2021, 14 271 (61·4%; 95% CI 60·8–62·0) individuals with a recent history of homelessness had received at least one dose of a COVID-19 vaccine and 11 082 (47·7%; 47·0–48·3) had received two doses; in comparison, over the same period, 86·6% of adults in the total Ontario population had received a first dose and 81·6% had received a second dose. In multivariable analysis, factors positively associated with COVID-19 uptake were one or more outpatient visits to a general practitioner (adjusted risk ratio [aRR] 1·37 [95% CI 1·31–1·42]), older age (50–59 years vs 18–29 years: 1·18 [1·14–1·22], ≥60 years vs 18–29 years: 1·27 [1·22–1·31]), receipt of an influenza vaccine in either of the two previous influenza seasons (1·25 [1·23–1·28]), being identified as homeless via a visit to a community health centre versus exclusively a hospital-based encounter (1·13 [1·10–1·15]), receipt of one or more SARS-CoV-2 tests between March 1, 2020, and Sept 30, 2021 (1·23 [1·20–1·26]), and the presence of chronic health conditions (one condition: 1·05 [1·03–1·08]; two or more conditions: 1·11 [1·08–1·14]). By contrast, living in a smaller metropolitan region (aRR 0·92 [95% CI 0·90–0·94]) or rural location (0·93 [0·90–0·97]) versus large metropolitan regions were associated with lower uptake.InterpretationIn Ontario, COVID-19 vaccine coverage among adults with a recent history of homelessness has lagged and, as of Sept 30, 2021, was 25 percentage points lower than that of the general adult population in Ontario for a first dose and 34 percentage points lower for a second dose. With high usage of outpatient health services among individuals with a recent history of homelessness, better utilisation of outpatient primary care structures might offer an opportunity to increase vaccine coverage in this population. Our findings underscore the importance of leveraging existing health and service organisations that are accessed and trusted by people who experience homelessness for targeted vaccine delivery.FundingThe Public Health Agency of Canada.TranslationFor the French translation of the abstract see Supplementary Materials section.

Mental Health Consequences of the COVID-19 Pandemic Among Ontario's Youth: A Cross-Sectional Study.

The coronavirus disease 2019 (COVID-19) pandemic has had a significant impact on the mental health and wellbeing of Ontario's youth. Our study investigated the psychological impacts of COVID-19 on the pediatric population of Ontario, using a survey derived from the Revised Children's Anxiety and Depression Scale (RCADS) system to identify children who may benefit from seeking professional help. Our cross-sectional study examined the potential risk factors that contributed to worsening mental health and wellbeing in children, including changes in sleep patterns, appetite, and physical activity levels, as well as the diagnosis of a family member with COVID-19. Our study found that 24%, 9.4%, and 15.5% of participants exhibited symptoms of depression, anxiety, and obsessive-compulsive disorder (OCD), respectively, according to the RCADS system. Furthermore, there were significant associations between the presence of symptoms and the diagnosis of a family member with COVID-19 or a frontline worker in the family. This suggests a need to create interventions to support the families of frontline workers and those directly affected by a COVID-19 diagnosis.

COVID-19 Vaccination Uptake Among Individuals With Immune-mediated Inflammatory Diseases in Ontario, Canada, Between December 2020 and October 2021: A Population-based Analysis

We assessed coronavirus disease 2019 (COVID-19) vaccine uptake among individuals with immune-mediated inflammatory diseases (IMIDs) and the Ontario general population. We studied all residents aged ≥ 16 years who were alive and enrolled in the Ontario Health Insurance Plan as of December 14, 2020, when vaccination commenced (n = 12,435,914). Individuals with rheumatoid arthritis (RA), ankylosing spondylitis (AS), psoriatic arthritis (PsA), psoriasis (PsO), and inflammatory bowel disease (IBD) were identified using established disease-specific case definitions applied to health administrative data. Vaccination status was extracted from the provincial COVaxON registry. Weekly cumulative proportions of first and second doses up until October 3, 2021, were expressed as the vaccinated percentage of each disease group, compared to the general Ontario population, and stratified by age. By October 3, 2021, the cumulative percentage with at least 1 dose was 82.1% for the general population, 88.9% for those with RA, 87.4% for AS, 90.6% for PsA, 87.3% for PsO, and 87.0% for IBD. There was also a higher total cumulative percentage with 2 doses among IMIDs (83.8-88.2%) vs the general population (77.9%). The difference was also evident when stratifying by age. Individuals with IMIDs in the youngest age group initially had earlier uptake than the general population but remain the lowest age group with 2 doses (70.6% in the general population vs. 73.7-79.2% across IMID groups). While implementation of COVID-19 vaccination programs has differed globally, these Canadian estimates are the first to reassuringly show higher COVID-19 vaccine uptake among individuals with IMIDs.

COVID‐19–related stressors, family functioning and mental health in Canada: Test of indirect effects

AbstractObjectiveThe purpose of this study was to examine how family relationships relate to stress and mental health during the COVID‐19 pandemic response in Ontario, Canada.BackgroundGenerally, families are pillars of strength during times of stress and burden. However, enduring stressors, such as the COVID‐19 pandemic, may challenge the cohesion and caregiving functions of families. Researchers are just beginning to explore stressors associated with the COVID‐19 pandemic, family functioning, and mental health in the general population. Rooted in stress process theory, the current study disentangles the complex pathways through which COVID‐19‐pandemic–related stressors and family cohesion and family conflict are associated with the mental health of the general population in Ontario, Canada.MethodData were collected using an online survey from April 22, 2020, to May 22, 2020. Through convenience sampling, 933 individuals were recruited from the general population in Ontario, Canada.ResultsFindings suggest that COVID‐19‐pandemic–related stressors are associated with anxiety directly and indirectly through eroding family cohesion and exacerbating family conflicts.ConclusionBy looking into family cohesion and family conflicts simultaneously, this investigation has taken a nuanced approach to studying the influence of COVID‐19‐pandemic–related stressors on family functioning.ImplicationsThese findings suggest that efforts to assist families in bolstering cohesiveness may be helpful. Further, diminishing family conflicts, especially during community or global disasters, such as epidemics, pandemics, or natural disasters, should be a focus in both practice and future research.

Evaluating the Prognostic Implication of the Collins Histology Scoring System in a Pediatric Eastern Ontario Population With Eosinophilic Esophagitis.

Collins et al developed a histology scoring system (EoE HSS) to assess multiple pathologic features. The aim of this study is to identify if the EoE HSS can better detect endoscopic and symptom improvement vs the Peak Eosinophilic Count (PEC). A retrospective chart review was performed for patients during 2014-2016. All patients ≤18years old with a diagnosis of EoE and whose records included initial and follow-up upper gastrointestinal endoscopies were included. Severity and extent of endoscopic features were scored using 8 parameters, from normal to maximum change for each location of the esophageal biopsy. Forty patients with EoE were included in the study, of which 35 (87.5%) patients demonstrated symptom and 25 (62.5%) endoscopic improvement at the time of follow-up. In the proximal esophagus, the EoE HSS outperformed the change in eosinophil count of the Children's Hospital of Eastern Ontario (CHEO) practice in predicting endoscopic improvement by 16.8% when examining the change in grade and 17.1% when examining the change in stage scores. At our institution, adoption of the EoE HSS in assessing biopsies of EoE patients might be warranted, compared to the traditional practice. However, a bigger sample size may give a more robust difference in all locations.

Comorbid conditions as risk factors for West Nile neuroinvasive disease in Ontario, Canada: a population-based cohort study.

West Nile neuroinvasive disease (WNND) is a severe neurological illness that can result from West Nile virus (WNV) infection, with long-term disability and death being common outcomes. Although WNV arrived in North America over two decades ago, risk factors for WNND are still being explored. The objective of this study was to identify WNND comorbid risk factors in the Ontario population using a retrospective, population-based cohort design. Incident WNV infections from laboratory records between 1 January 2002 - 31 December 2012 were individually-linked to health administrative databases to ascertain WNND outcomes and comorbid risk factors. WNND incidence was compared among individuals with and without comorbidities using risk ratios (RR) calculated with log binomial regression.Three hundred and forty-five individuals developed WNND (18.3%) out of 1884 WNV infections. West Nile encephalitis was driving most associations with comorbidities. Immunocompromised (aRR 2.61 [95% CI 1.23-4.53]) and male sex (aRR 1.32 [95% CI 1.00-1.76]) were risk factors for encephalitis, in addition to age, for which each 1-year increase was associated with a 2% (aRR 1.02 [95% CI 1.02-1.03]) relative increase in risk. Our results suggest that individuals living with comorbidities are at higher risk for WNND, in particular encephalitis, following WNV infection.

Impacts of harvested species declines on Indigenous Peoples’ food sovereignty, well-being and ways of life: a case study of Anishinaabe perspectives and moose

Global declines in wildlife are increasing the vulnerability of Indigenous communities to food insecurity. Meanwhile, many colonial policies continue to ignore social-ecological relationships that have traditionally maintained a balance between wildlife and Indigenous Peoples’ subsistence needs. We provide a case study on perspectives and insights from three Anishinaabe Nations in Ontario, Canada on the importance of a traditional food, moose (<em>mooz</em> [Nishnaabemowin]; <em>Alces alces</em>), and how changes in the moose population are affecting food security, well-being, and ways of life. In partnership with each Nation, we conducted interviews with community members and related observations on change in the moose population to estimates of moose abundance and non-Indigenous harvest collected by the Ontario provincial government over a 16-year time frame (2001–2016). Moose was described as important for subsistence needs as well as for maintaining Anishinabek culture, traditions, and identity within each community. A decline in the moose population was observed by most participants, which corresponded with provincial data on moose abundance. Additionally, the number of non-Indigenous hunters per moose harvested on traditional territories increased linearly over time, and community members expressed concern over how the province was managing moose. The effects of moose decline in the communities included reduced food security and health, increased financial costs due to both relying more on store-bought foods and having to travel further to harvest moose, as well as a decline in the practice of traditions and ceremonies surrounding moose harvest and passing this knowledge on to younger generations. Despite the potential impacts on Indigenous subsistence harvest, there is a lack of collaborative decision-making with Indigenous communities on moose population and harvest management in Ontario. Using community perspectives and insights, we discuss how autonomous moose monitoring can support and facilitate co-management and collaborative decision-making to reinstate Indigenous food sovereignty.

Integrating regional and site-level data to assess drivers of population decline in a threatened aerial insectivorous bird

Knowledge of demographic processes is essential for understanding population dynamics and developing appropriate conservation strategies under global change. However, it is often challenging to collect the necessary population and demographic data to understand population dynamics. Integrated population modeling (IPM) provides an opportunity to combine population survey and demographic data from different sources. We developed an IPM and applied it to jointly analyze 15 years (2004–2018) of regional North American Breeding Bird Survey and site-level capture-recapture and age-ratio data for a barn swallow (Hirundo rustica) population in Ontario, Canada. We aimed to identify key demographic parameters and tested hypothesized environmental drivers to understand population declines of this species. Our results showed that the study population had declined by about 2% annually during our study period, which was mainly contributed by changes in net immigration and adult apparent survival. In particular, low net immigration in a few years of our study period seemed to be the main reason of population decline. Furthermore, we found that warmer temperatures in April when barn swallows return to breeding grounds had a positive effect on adult survival, while warmer temperatures during the breeding period in May–June had a negative effect on productivity. Our results indicate vulnerability of the species to inclement weather during the breeding season, suggesting potential population recovery by adopting conservation strategies that buffer climatic threats. Moreover, our IPM provides a foundation for future monitoring programs that intend to combine and maximize the utility of large-scale population counts and fine-scale demographic data.

A population-based, retrospective cohort study analyzing contemporary trends in the surgical management of urinary stone disease in adults.

We aimed to review the trends and incidence of surgical intervention for adults with upper urinary tract stones in Ontario, Canada, and to hypothesize potential causes for the observed changes. We carried out a retrospective, population-based cohort study using administrative databases held at the Institute of Clinical Evaluative Sciences (ICES) to identify all adults (≥18 years) who underwent surgical treatment for urolithiasis, defined by records using a combination of both hospital and physician billing from 2002-2019. Descriptive statistics were used to summarize baseline patient demographics, and surgical trends were analyzed using the Cochrane-Armitage test for trend. From 2002-2019, 140 263 patients were treated surgically for urolithiasis. During this time period, the total number of surgically treated stone disease increased by 80.5%. By type of procedure, percutaneous nephrolithotomy (PCNL) increased by 187% and ureteroscopy (URS) increased by 158%, while the number of shockwave lithotripsy (SWL) declined by 31.4%. The adult population in Ontario in the years evaluated grew by 24.4%. The number of surgical procedures per 100 000 people over this time grew by 45.3%. For every 1% increase in the population, there was a 2.6% rise in stone-related surgical procedures. The number of stone-related surgical procedures performed rose significantly and cannot be accounted for by population growth alone. This rise was proportionally larger in the female population, further supporting a narrowing of the gender gap in urinary stone disease. The reasons for the increase are likely multifactorial and may imply an increasing incidence of surgically treated stone disease. The change in the proportion of URS and SWL performed may demonstrate a continued shift in surgical preference or may be reflective of resource limitations and availability. The increase in PCNL volumes may also suggest a greater complexity of cases. These findings should be considered for future resource planning and require further study.

Rates of opioid agonist treatment prescribing in provincial prisons in Ontario, Canada, 2015–2018: a repeated cross-sectional analysis

ObjectiveTo describe opioid agonist treatment prescribing rates in provincial prisons and compare with community prescribing rates.DesignWe used quarterly, cross-sectional data on the number and proportion of people prescribed opioid agonist...

Examining Variations in the Prevalence of Diagnosed Mood or Anxiety Disorders Among Migrant Groups in Ontario, 1995-2015: A Population-Based, Repeated Cross-Sectional Study.

International evidence on the frequency of mood or anxiety disorders among migrant groups is highly variable, as it is dependent on the time since migration and the socio-political context of the host country. Our objective was to estimate trends in the prevalence of diagnosed mood or anxiety disorders among recent (<5 years in Canada) and settled (5-10 years in Canada) migrant groups, relative to the general population of Ontario, Canada. We used a repeated cross-sectional design consisting of four cross-sections spanning 5 years each, constructed using health administrative databases from 1995 to 2015. We included all Ontario residents between the ages of 16 and 64 years. We assessed differences in the prevalence of mood or anxiety disorders adjusting for age, sex, and neighbourhood-level income. We further evaluated the impact of migrant class and region of birth. The prevalence of mood or anxiety disorders was lower among recent (weighted mean = 4.10%; 95% confidence interval [CI], 3.59% to 4.60%) and settled (weighted mean = 4.77%; 95% CI, 3.94% to 5.61%) migrant groups, relative to the general population (weighted mean = 7.39%; 95% CI, 6.83% to 7.94%). Prevalence estimates varied greatly by region of birth and migrant class. We found variation in prevalence estimates over time, with refugee groups having the largest increases between 1995 and 2015. Our findings highlight the complexity of mood and anxiety disorders among migrant groups, and that not all groups share the same risk profile. These results can be used to help inform health service allocation and the development of supportive programs for specific migrant groups.

Bottom–up trophic effects on fisher Pekania pennanti harvest age structure: associations with mast, voles and owls

Harvest management quotas for fishers Pekania pennanti in some jurisdictions are estimated from the previous year's harvest, and stem from the hypothesis that age ratios in the harvest are largely influenced by ‘top–down’ trapping pressure. The influence of ‘bottom–up’ food supply on fisher harvest age ratios might be underappreciated, which could result in a misallocation of quotas in management planning. We assessed a variety of data sources to test the influence of bottom–up processes on fisher populations in Ontario, Canada. We found evidence that bottom–up trophic effects influence the harvested fisher age structure in some regions of Ontario. Evidence also suggests that harvest pressure had little top–down influence on age ratios over the course of our study, and that basing management strategies on this assumption may lead to unintentional overharvest in years of low productivity. We suggest several trophic linkages with potential to facilitate fisher management, including connections among berry and seed crops, small mammals and northern saw-whet owls Aegolius acadicus.

First-Line Palliative Chemotherapy for Esophageal and Gastric Cancer: Practice Patterns and Outcomes in the General Population.

Clinical trials have shown that palliative chemotherapy (PC) improves survival in patients with incurable esophageal and gastric cancer; however, outcomes achieved in routine practice are unknown. We describe treatment patterns and outcomes among patients treated in the general population of Ontario, Canada. The Ontario Cancer Registry was used to identify patients with esophageal or gastric cancer from 2007 to 2016, and data were linked to other health administrative databases. Patients who received curative-intent surgery or radiotherapy were excluded. Factors associated with the receipt of PC were determined using logistic regression. First-line PC regimens were categorized, and trends over time were reported. Survival was determined using the Kaplan-Meier method. The cohort included 9,848 patients; 22% (2,207 of 9,848) received PC. Patients receiving PC were younger (mean age, 63 v 74 years; P < .0001) and more likely male (71% v 65%; P < .0001). Thirty-seven percent of non-PC patients saw a medical oncologist in consultation. Over the study period, utilization of PC increased (from 11% in 2007 to 19% in 2016; P < .0001), whereas the proportion of patients receiving triplet regimens decreased (65% in 2007 to 56% in 2016; P = .04). In the PC group, the median overall and cancer-specific survival from treatment initiation was 7.2 months. One fifth of patients with incurable esophageal and gastric cancer in the general population receive PC. Median survival of patients treated in routine practice is inferior to that in clinical trials. Only one third of patients not treated with PC had consultation with a medical oncologist. Further work is necessary to understand low utilization of PC and medical oncology consultation in this patient population.

Challenging the HIV Epidemic in Ontario Through PrEP and HIV Testing

The Ontario HIV Treatment Network (OHTN) is a non-profit network which collaborates with health clinics, AIDS service and community organizations, and policy leaders in order to improve the health and wellbeing of people living with and at risk of HIV. I joined the OHTN as a member of the Collective Impact team, with a focus on examining the barriers and facilitators to Pre-Exposure Prophylaxis (PrEP) uptake in Ontario. PrEP is a once-daily pill which is highly effective in preventing HIV infections for HIV-negative people, however usage remains relatively low in Ontario. In this role, I liaised with the Knowledge Synthesis team at OHTN to collect, analyse, and synthesize recent scientific literature on Pre and Post-exposure prophylaxis (PEP) in order to create a comprehensive annotated bibliography on PrEP research. Key findings were drawn from the research to identify potential next steps to increase PrEP use for priority populations in Ontario. Findings from the annotated bibliography were presented to OHTN staff, and have been used to assist in the development of two PrEP study proposals; 1) a cisgender and transgender women-focused PrEP education package and HIV risk screening tool, and 2) a pharmacist-led PrEP delivery pilot. I also worked with the Testing and Clinical Initiatives team at the OHTN, to aid in the implementation and evaluation of two HIV-testing projects: the GetaTest pharmacy-based HIV-testing study, and the GetaKit HIV self-testing pilot program. In this role I drafted health communication materials; analysed survey data and drafted project reports for stakeholders; and provided perspectives on the HIV-care continuum, particularly on PrEP initiation, adherence, and efficacy. My work with the OHTN was important to public health because it sought to expand access to HIV testing and prevention services for priority populations in Ontario, including men who have sex with men, and cis and trans women.

Identification and Adjudication of Adverse Events Following Rectal Cancer Surgery: Observational Case Series in a Region of Ontario, Canada.

For patients undergoing rectal cancer surgery, we evaluated whether suboptimal preoperative surgeon evaluation of resection margins is a latent condition factor-a factor that is common, unrecognized, and may increase the risk of certain adverse events, including local tumour recurrence, positive surgical margin, nontherapeutic surgery, and in-hospital mortality. In this observational case series of patients who underwent rectal cancer surgery during 2016 in Local Health Integrated Network 4 region of Ontario (population 1.4 million), chart review and a trigger tool were used to identify patients who experienced the adverse events. An expert panel adjudicated whether each event was preventable or nonpreventable and identified potential contributing factors to adverse events. Among 173 patients, 25 (14.5%) had an adverse event and 13 cases (7.5%) were adjudicated as preventable. Rate of surgeon awareness of preoperative margin status was low at 50% and similar among cases with and without an adverse event (p = 0.29). Suboptimal surgeon preoperative evaluation of surgical margins was adjudicated a contributing factor in all 11 preventable local recurrence, positive margin, and nontherapeutic surgery cases. Failure to rescue was judged a contributing factor in the two cases with preventable in-hospital mortality. Suboptimal surgeon preoperative evaluation of surgical margins in rectal cancer is likely a latent condition factor. Optimizing margin evaluation may be an efficient quality improvement target.

Establishing a Provincial Registry for Recurrent Prostate Cancer: Providing Access to PSMA PET/CT in Ontario, Canada.

Prostate Specific Membrane Antigen (PSMA) positron emission tomography/computed tomography (PET/CT) is becoming established as a standard of care for the (re)staging of high-risk primary and prostate cancer recurrence after primary therapy. Despite the favorable performance of this imaging modality with high accuracy in disease detection, the availability of PSMA PET/CT varies across jurisdictions worldwide due to variability in the selection of PSMA PET/CT agent, regulatory approvals and funding. In Canada, PSMA based radiopharmaceuticals are still considered investigational new drug (IND), creating limitations in the deployment of these promising imaging agents. While regulatory approval rests with Health Canada, as a single payer health system, funding for Health Canada approved drugs and devices is decided by Provincial Health Ministries. Ontario Health (Cancer Care Ontario) (OH-CCO) is the agency of the Ministry of Health (MOH) in Ontario responsible for making recommendations to the MOH around the organization and funding of cancer services within Ontario (population of 15 million), and the PET Steering Committee of OH-CCO is responsible for providing recommendations on the introduction of new PET radiopharmaceuticals and indications. For Health Canada approved PET radiopharmaceuticals like 18F-FDG, OH-CCO (on behalf of the MOH) provides coverage based on levels of evidence and specific PET Registries are established to aid in real-world evidence collection to inform OH-CCO regarding emerging PET applications. In the case of PSMA PET/CT, adapting this model to an IND PSMA PET/CT agent, 18F-DCFPyL, necessitated the creation of a hybrid Registry-Study model to leverage the existing OH-CCO Registry structure while respecting the need for a Health Canada Clinical Trials Application (CTA) for the deployment of this agent in the province. Within the first 2 years of the registry, over 1700 men have been imaged resulting in a change in management (compared to pre-PET management plans) in over half of the men imaged. In this article, we describe the organization and deployment of the PSMA PET/CT (PREP) Registry throughout the province to provide access for men with suspected prostate cancer recurrence along with key stakeholder perspectives and preliminary results.

Diabetic Ketoacidosis and Mortality in People With Type 1 Diabetes and Eating Disorders.

To determine the risk of diabetic ketoacidosis (DKA) and all-cause mortality among adolescents and young adults with type 1 diabetes with and without an eating disorder. With use of population-level health care administrative data covering the entire population of Ontario, Canada, all people with type 1 diabetes aged 10-39 years as of January 2014 were identified. Individuals with a history of eating disorders were age- and sex-matched 10:1 with individuals without eating disorders. All individuals were followed for 6 years for hospitalization/emergency department visits for DKA and for all-cause mortality. We studied 168 people with eating disorders and 1,680 age- and sex-matched people without eating disorders. Among adolescents and young adults with type 1 diabetes, 168 (0.8%) had a history of eating disorders. The crude incidence of DKA was 112.5 per 1,000 patient-years in people with eating disorders vs. 30.8 in people without eating disorders. After adjustment for baseline differences, the subdistribution hazard ratio for comparison of people with and without eating disorders was 3.30 (95% CI 2.58-4.23; P < 0.0001). All-cause mortality was 16.0 per 1,000 person-years for people with eating disorders vs. 2.5 for people without eating disorders. The adjusted hazard ratio was 5.80 (95% CI 3.04-11.08; P < 0.0001). Adolescents and young adults with type 1 diabetes and eating disorders have more than triple the risk of DKA and nearly sixfold increased risk of death compared with their peers without eating disorders.

Ecological responses to elevated water temperatures across invasive populations of the round goby (Neogobius melanostomus) in the Great Lakes basin

Climate warming is expected to alter the distribution, abundance, and impact of non-native species in aquatic ecosystems. In laboratory experiments, we measured the maximum feeding rate and critical thermal maximum (CTmax) of an invasive Eurasian fish, the round goby (Neogobius melanostomus), acclimated to a range of temperatures (18–28 °C) reflecting current and projected future thermal conditions for the nearshore Great Lakes. Fish were collected from four distinct populations along a latitudinal gradient from the western basin of Lake Erie to Hamilton Harbour (Lake Ontario) and the upper St. Lawrence River. Thermal tolerance increased with acclimation temperature for populations in Lakes Erie and Ontario. However, the St. Lawrence River populations had lower acclimation capacity and exhibited an unexpected decline in CTmax at the highest acclimation temperature. Maximum feeding rates peaked at 18–24 °C and declined with temperatures above 24 °C. Northern populations in the basin appear poorly adapted to elevated temperatures such that their performance and impact could be reduced by climate warming. Thermal response data from latitudinally distributed populations are needed to inform invasive species risk assessment.