Development of the Canadian Marginalization Index: a new tool for the study of inequality

Travel distance to tertiary sarcoma centres does not influence oncological presentation or outcomes

Aims

Soft-tissue sarcomas (STSs) are rare cancers with centralized care advocated to consolidate resources and expertise. However, geographical challenges, particularly in countries like Canada, can increase travel distances for patients. The impact of travel distance on sarcoma presentation and outcomes remains unclear, particularly in single-payer healthcare systems with centralized care.

Methods

A retrospective cohort analysis was conducted on 1,570 patients with STS who underwent surgical resection at a Canadian tertiary referral centre between January 2010 and January 2021. Patients were divided into those living ≤ 50 km and > 50 km from the centre. Demographics, tumour characteristics, treatment methods, and survival outcomes were analyzed. A Cox regression model was constructed to evaluate predictors of overall survival.

Results

Patients living > 50 km from the centre (n = 700) travelled a mean of 176 km (SD 250), while those ≤ 50 km (n = 870) travelled a mean of 24.8 km (SD 13.8). There were no significant differences in disease presentation, time to definitive treatment, use of systemic therapies, or functional outcomes between the two groups. The two-year and five-year overall survival rates were similar between the groups (83.1% (95% CI 80.1% to 86.1%) vs 83.8% (95% CI 81.8% to 85.8%) and 72.1% (95% CI 69.1% to 75.1%) vs 72.5% (95% CI 69.5% to 75.5%), respectively). The regression model demonstrated that age, higher tumour grade, depth, and lower income were predictive of worse overall survival, while distance travelled was not an independent predictor of survival.

Conclusion

Contrary to previous studies, our findings suggest that travel distance did not influence disease presentation or survival outcomes in STS patients treated at a centralized sarcoma centre. This challenges previous notions regarding the impact of travel distance on cancer outcomes, and supports the effectiveness of centralized care models, even in geographically vast regions.

The Impact of Chronic Obstructive Pulmonary Disease on Immune Checkpoint Inhibitor Effectiveness in Non-small Cell Lung Cancer: A Population Health Study

SUMMARY

Chronic obstructive pulmonary disease (COPD) and lung cancer are associated diseases. COPD confers a negative prognosis in NSCLC, but the clinical benefit of immune checkpoint inhibitors (ICI) in this population is unclear. A population-level analysis of patients in Ontario, Canada was performed through the ICES (formerly known as the Institute for Clinical Evaluative Sciences) administrative database. Patients with NSCLC and treated with PD-1/PD-L1 immune checkpoint inhibitors between Jan 2010 and Dec 2020 were included. Overall survival (OS) was estimated using the Kaplan-Meier method and compared using Cox proportional hazards regression. Hospitalizations and duration of treatment were compared secondarily using logistic and linear regression. A total of 4306 patients received ICI and 54% of patients had a diagnosis of COPD. Median (95% CI) OS was 9.2 (8.5-9.9) months for patients with COPD and 8.2 (7.3-8.8) for patients without COPD, which was not significantly different (adjusted hazard ratio (aHR) = 0.94, 95% CI, 0.87-1.01, P = 0.092). Similarly, the median time on treatment was not different (85 vs. 99 days, multivariable P = 0.10). However, the 90-day hospitalization rate was decreased in the COPD population (multivariable odds ratio 0.76, 95% CI 0.62-0.94, P = 0.011). Among patients with NSCLC receiving ICI, our data suggest that a diagnosis of COPD does not result in shortened treatment, poorer survival, or higher rates of hospitalization. COPD itself should not be considered a contraindication to ICI.

Development and Validation of Prediction Models for Perceived and Unmet Mental Health Needs in the Canadian General Population: Model-Based Synthetic Estimation Study

Background

Research has shown that perceptions of a mental health need are closely associated with service demands and are an important dimension in needs assessment. Perceived and unmet mental health needs are important factors in the decision-making process regarding mental health services planning and resources allocation. However, few prediction tools are available to be used by policy and decision makers to forecast perceived and unmet mental health needs at the population level.

Objective

We aim to develop prediction models to forecast perceived and unmet mental health needs at the provincial and health regional levels in Canada.

Methods

Data from 2018, 2019, and 2020 Canadian Community Health Survey and Canadian Urban Environment were used (n=65,000 each year). Perceived and unmet mental health needs were measured by the Perceived Needs for Care Questionnaire. Using the 2018 dataset, we developed the prediction models through the application of regression synthetic estimation for the Atlantic, Central, and Western regions. The models were validated in the 2019 and 2020 datasets at the provincial level and in 10 randomly selected health regions by comparing the observed and predicted proportions of the outcomes.

Results

In 2018, a total of 17.82% of the participants reported perceived mental health need and 3.81% reported unmet mental health need. The proportions were similar in 2019 (18.04% and 3.91%) and in 2020 (18.1% and 3.92%). Sex, age, self-reported mental health, physician diagnosed mood and anxiety disorders, self-reported life stress and life satisfaction were the predictors in the 3 regional models. The individual based models had good discriminative power with C statistics over 0.83 and good calibration. Applying the synthetic models in 2019 and 2020 data, the models had the best performance in Ontario, Quebec, and British Columbia; the absolute differences between observed and predicted proportions were less than 1%. The absolute differences between the predicted and observed proportion of perceived mental health needs in Newfoundland and Labrador (-4.16% in 2020) and Prince Edward Island (4.58% in 2019) were larger than those in other provinces. When applying the models in the 10 selected health regions, the models calibrated well in the health regions in Ontario and in Quebec; the absolute differences in perceived mental health needs ranged from 0.23% to 2.34%.

Conclusions

Predicting perceived and unmet mental health at the population level is feasible. There are common factors that contribute to perceived and unmet mental health needs across regions, at different magnitudes, due to different population characteristics. Therefore, predicting perceived and unmet mental health needs should be region specific. The performance of the models at the provincial and health regional levels may be affected by population size.

The Relationship Between Area-Level Marginalization and Overall Survival of Patients with Soft Tissue Sarcoma in Ontario: A Retrospective Cohort Study

BACKGROUND

Socioeconomic status and community marginalization can impact overall survival and functional outcome in patients with cancer. However, this association has not been determined in patients with soft tissue sarcoma (STS) within Canada. The primary aim of this study was to determine the impact of marginalization on STS 5-year overall survival.

PATIENTS AND METHODS

We conducted a retrospective cohort study of patients presenting with primary or locally recurrent STS who underwent surgical resection between January 2010 and December 2021. Marginalization was determined using the Ontario Marginalization Index (ON-Marg), with subdomains including Ethnic Concentration, Material Resources, Household Dwelling, and Labor Dependency, and patients were stratified into quintiles (Q1 = least marginalized; Q5 = most marginalized). The association between marginalization and overall survival was determined using Kaplan-Meier curves and a multivariate Cox proportional hazards model.

RESULTS

When adjusted for age and grade of disease, 5-year overall survival was not impacted by Ethnic Concentration (75.2% Q1 vs. 80.5% Q5). However, 5-year overall survival was significantly affected by increasing marginalization within Material Resources (81.9% Q1 vs. 69% Q5), Household Dwelling (82.2% Q1 vs. 69.6% Q5), and Labor Dependency (75.4% Q1 vs. 67.3% Q5). Significant differences across quintiles with regard to 1-year functional outcomes were noted with the Toronto Extremity Salvage Score, while nonsignificant changes were noted with the Musculoskeletal Tumor Society Score-93.

CONCLUSIONS

This study is the first to demonstrate marginalization as an independent risk factor adversely impacting 5-year overall survival of STS in Canada's single-payer universal healthcare system.

Impact of the COVID-19 pandemic on breast cancer surgeries in a Canadian population

PURPOSE

The COVID-19 pandemic significantly impacted breast cancer (BC) surgeries. Most studies showing reduced BC surgical volumes during the pandemic are from single institutions, few have described volume changes in different types of surgical procedures. This study aimed to assess the impact of the pandemic on BC surgery volumes and types at a population level.

METHODS

Patients diagnosed with BC between January 1, 2018, and June 25, 2022, in Ontario, Canada, were analysed from population-based datasets. Time periods were defined as pre-pandemic (Jan 2018-Mar 2020), immediate pandemic (Mar-Jun 2020), and peri-pandemic (Jun 2020-Jun 2022). Weekly BC surgery volume and type (lumpectomy, mastectomy, or mastectomy with immediate reconstruction) were evaluated using segmented negative binomial regression models.

RESULTS

Among 44 226 patients, 50 440 surgeries were performed. Weekly BC surgeries decreased by 16.9% during the immediate pandemic compared to pre-pandemic levels (180.5 vs. 217.1; p = 0.03). Surgical volumes recovered to pre-pandemic levels by June 2021. Mastectomies represented a higher proportion of BC surgeries during the pandemic (31.1% pre, 36.3% immediate, 32.4% peri-pandemic; p < 0.01). The proportion of mastectomies with immediate reconstruction remained stable during the immediate pandemic but increased in the peri-pandemic (20.1% vs. 17%; p < 0.01).

CONCLUSION

There was a significant reduction in all BC surgeries during the pandemic. Mastectomies accounted for a higher proportion of BC surgeries in the pandemic period however access to reconstruction was maintained. Surgical volumes recovered within a year despite ongoing pandemic hospitalizations. Future studies are needed to explore the pandemic's long-term impact on BC care.

Impact of a 10-year shift in ambient air quality on mortality in Canada: a causal analysis of multiple pollutants

BACKGROUND

The impact of past air quality improvements on health and equity at low pollution levels near the revised WHO air quality guidelines remains largely unknown. Less is known about the influence of simultaneous reductions in multiple major pollutants. Leveraging real-world improvements in air quality across Canada, we sought to directly evaluate their health benefits by quantifying the impact of a joint shift in three criteria pollutants on mortality in a national cohort.

METHODS

In this population-based cohort study, we assembled a cohort of 2·7 million adults living in Canada in 2007 who were followed up through 2016. Annual mean concentrations of fine particulate matter (PM2·5), nitrogen dioxide (NO2), and ozone (O3) were assigned to participants' residential locations. For each pollutant individually and combined, we conducted a causal analysis of the impact of the decadal shift in annual exposure from the pre-baseline level (2004-06) on the risk of non-accidental mortality using the parametric g-formula, a structural causal model. To check the robustness of our results, we conducted multiple sensitivity analyses, including exploring alternative exposure scenarios. We also evaluated differential benefits across regions and socio-demographic subgroups.

FINDINGS

Between 2007 and 2016, annual mean exposures to PM2·5 and NO2 decreased (from 7·1 μg/m3 [SD 2·3] to 5·5 μg/m3 [1·9] for PM2·5 and from 11·1 ppb [SD 6·6] to 8·0 ppb [4·9] for NO2), whereas O3 declined initially and then rebounded (from 38·6 [SD 8·3] ppb to 36·0 [6·0] ppb and then 38·1 [5·4] ppb). Compared to pre-baseline (2004-06) levels, the joint change in the pollution exposures beginning in 2007 resulted in, per million population, 70 (95% CI 29-111) fewer deaths by 2009, 416 (283-549) fewer deaths by 2012, and 609 (276-941) fewer deaths by 2016, corresponding to a -0·7% change in mortality risk over the decade. Stratified analyses showed greater beneficial impacts in men, adults aged 50 years and older, low income-earners, and residents in regions undergoing substantial air quality improvements. Had all regions experienced pollution reductions similar to the most improved region, approximately three times as many deaths would have been averted (2191 fewer deaths per million). Conversely, if the observed air quality improvements had been delayed in all regions by 3 years, there would have been 429 more deaths per million by 2016.

INTERPRETATION

In Canada, substantial health gains were associated with air quality improvements at levels near the revised WHO guidelines between 2007 and 2016, with notable heterogeneity observed across socio-demographic subgroups and regions. These findings indicate that modest declines in air pollution can considerably improve health and equity, even in low-exposure environments.

FUNDING

Health Canada.

Social inequalities in youth mental health in Canada, 2007-2022: a population-based repeated cross-sectional study

PURPOSE

Rising concern surrounds youth mental health in Canada, with growing disparities between females and males. However, less is known about recent trends by other sociodemographic factors, including sexual orientation, ethnocultural background, and socioeconomic status.

METHODS

This study analyzed data from 96 683 youths aged 15-24 who participated in the nationally representative Canadian Community Health Survey (CCHS) between 2007 and 2022. Trends in absolute and relative inequalities in poor/fair self-rated mental health (SRMH) by sex, sexual orientation, racialized and Indigenous identity, and socioeconomic conditions were assessed.

RESULTS

The percent of youths reporting poor/fair SRMH quadrupled from 4.3% in 2007-08 to 20.1% in 2021-22. During the same period, absolute inequalities in SRMH increased by 9.9% points (95% CI: 6.6, 12.9) for females compared to males, 11.4% points (95% CI: 4.6, 18.2) for Indigenous versus non-racialized youth, and 15.4% points (95% CI: 5.7, 25.1) for youth (aged 18-24) identifying as lesbian, gay, or bisexual (LGB) compared to heterosexual.

CONCLUSION

The sustained deterioration in youth SRMH over the past decade and a half has been accompanied by widening inequalities across several dimensions important for health equity in Canada. Action is needed to identify and implement effective programs and policies to support youth mental health and address disparities.

Examining the association between public health unit spending and adolescent substance use

Background

Based on the socio-ecological model of health, socioeconomic policy is an important determinant of population health. Spending decisions by public health units (PHU) have been shown to be associated with population health outcomes. Some studies have found greater PHU spending to be associated with improved population health, while others report mixed findings, warranting further research. The objective of this study was to investigate the association between per capita PHU spending and self-reported substance use among Canadian adolescents.

Methods

Cross-sectional, multilevel modelling was conducted using student data from the 7th wave (2018/19) of the Cannabis use, Obesity, Mental health, Physical activity, Alcohol use, Smoking, and Sedentary behaviour (COMPASS) study, as well as spending data from the audited financial statements of Ontario's PHUs. The sample included 29,056 students in grades 9-12 attending 61 secondary schools in 15 PHUs across Ontario. Substance use was measured as the self-reported use of alcohol, cannabis, cigarettes and e-cigarettes, at least once per month on average.

Results

Approximately 50 % of the study sample was female and the majority identified as being White. Per capita spending ranged from $54.07 to $224.95, with a median spending amount of $89.62. The highest quartile of PHU spending was significantly associated with higher alcohol use (adjusted odds ratio (AOR): 1.41, 95 % CI: 1.04, 1.91), binge drinking (AOR: 1.71, 95 % CI: 1.18, 2.48), and cigarette use (AOR: 2.19, 95 % CI: 1.23, 3.91) in adolescents, while the second highest quartile was associated with lower e-cigarette use (AOR: 0.74, 95 % CI: 0.56, 0.98), relative to the lowest quartile.

Conclusion

Public health spending is associated with adolescent substance use. The present study reports mixed results, warranting further prospective research to explore the directions and mechanisms of the associations found.

An audit and feedback-based intervention to improve diabetes management in the year after transfer to adult type 1 diabetes care: A multi-center quasi-experimental study

AIM

To test whether an audit and feedback-based intervention improved HbA1c 12 months after transfer to type 1 diabetes adult care.

METHODS

Multi-centre, quasi-experimental pre-post study of an AF-based intervention targeting paediatric diabetes teams, which encouraged the implementation of an evidence-informed structured transition process at five paediatric diabetes centres in Ontario, Canada. Participants entered the study at their final paediatric visit. A parallel control cohort was ascertained using population-based administrative datasets. The primary outcome was HbA1c 12 months after transfer. The main exposure was the study period: pre-implementation (June 2018-May 2019); early-implementation (June 2019-September 2020); and late-implementation (October 2020-September 2021). Multivariable linear regression models were fit separately in each cohort.

RESULTS

There were 449 and 2844 individuals in the intervention and control cohorts, respectively. Twelve months after transfer, participants in the late-implementation intervention cohort had an HbA1c that was, on average, 0.41% lower than participants in the pre-implementation period (p = 0.016). Among the control cohort, there was no significant difference in the HbA1c 12 months after transfer between study periods.

CONCLUSIONS

We found an effect of the intervention on glycaemic management one year following transfer to adult care. Future work will focus on refining and testing the effectiveness of the intervention in an expanded number of study sites and in collaboration with adult diabetes care providers.

Development of a territory-wide household-based composite index for measuring relative distribution of households by economic status in individual small areas throughout Hong Kong

BACKGROUND

Many countries have developed their country/nation-wide multidimensional area-based index on deprivation or socioeconomic status for resource allocation, service planning and research. However, whether each geographical unit proxied by a single index is sufficiently small to contain a relatively homogeneous population remains questionable. Globally, this is the first study that presents the distribution of domestic households by the territory-wide economic status index decile groups within each of the 2,252 small subunit groups (SSUGs) throughout Hong Kong, with a median study population of 1,300 and a median area of 42,400 m2.

METHODS

The index development involved 248,000 anonymized sampled household-based data collected from the population census, representing 2·66 million domestic households and 6·93 million population in mid-2021. Our composite index comprises seven variables under income-/wealth-related and housing-related domains with weights determined using the analytic hierarchy process. After ranking all households from the most to the least well-off according to the numeric/ordinal value of each variable and then calculating their weighted rank scores, they were segregated into ten deciles from D1 (top 10% most well-off) to D10 (bottom 10%). Their relative distribution was summarized in a three-dimensional ternary plot to distinguish patterns across the 2,252 SSUGs within the 18 administrative districts.

RESULTS

In Hong Kong, of the 2,252 SSUGs, only one-quarter contain a homogeneous composition of households with similar economic status, while the other three-quarters are heterogeneous to varying extents. Of the 18 administrative districts, only two are concentrated with more homogeneously well-off SSUGs.

CONCLUSIONS

Small-sized geographical units may contain a heterogeneous composition of households with diverse economic statuses, underlying the need for more precise information to quantify their relative distribution. Results of this study are disseminated via an online interactive map dashboard ( https://experience.arcgis.com/experience/‌b4c7643feb9043eb94b3add386c4b71c /) which can serve as a versatile planning tool capable of performing analysis at different varying geographic scales for community-based resource prioritization, service planning and research across different domains.

Airborne Nanoparticle Concentrations Are Associated with Increased Mortality Risk in Canada's Two Largest Cities

Rationale: Outdoor fine particulate air pollution (particulate matter with an aerodynamic diameter ⩽2.5 μm; PM2.5) contributes to millions of deaths around the world each year, but much less is known about the long-term health impacts of other particulate air pollutants, including ultrafine particles (a.k.a. nanoparticles), which are in the nanometer-size range (<100 nm), widespread in urban environments, and not currently regulated. Objectives: We sought to estimate the associations between long-term exposure to outdoor ultrafine particles and mortality. Methods: Outdoor air pollution levels were linked to the residential addresses of a large, population-based cohort from 2001 to 2016. Associations between long-term exposure to outdoor ultrafine particles and nonaccidental and cause-specific mortality were estimated using Cox proportional hazards models. Measurements and Main Results: An increase in long-term exposure to outdoor ultrafine particles was associated with an increased risk of nonaccidental mortality (hazard ratio = 1.073; 95% confidence interval = 1.061-1.085) and cause-specific mortality, the strongest of which was respiratory mortality (hazard ratio = 1.174; 95% confidence interval = 1.130-1.220). We estimated the mortality burden for outdoor ultrafine particles in Montreal and Toronto, Canada, to be approximately 1,100 additional nonaccidental deaths every year. Furthermore, we observed possible confounding by particle size, which suggests that previous studies may have underestimated or missed important health risks associated with ultrafine particles. Conclusions: As outdoor ultrafine particles are not currently regulated, there is great potential for future regulatory interventions to improve population health by targeting these common outdoor air pollutants.

Relationship Between Social Deprivation and Access to Catheter Ablation for Atrial Fibrillation: A Population-Level Study

Background

Access to catheter ablation for atrial fibrillation (AF) may vary due to social deprivation.

Objectives

This study sought to characterize the correlation between our outcomes of interest (rates of AF diagnoses, ablation referrals, and procedures) and the association between social deprivation and our outcomes.

Methods

Rates and correlations of AF diagnoses, ablation referrals, and procedures were reported across 49 census divisions in Ontario, Canada. We used the Ontario Marginalization Index to determine the relationship between dependency, material deprivation, ethnic concentration, and residential instability and our outcomes.

Results

Between April 2016 and March 2020, there were 146,366 patients diagnosed with AF; 6,506 patients were referred for ablation; and 4,673 patients underwent de novo ablation. The median age was 72 years (IQR: 61-81 years; 45% female) for the AF cohort and 62 years (IQR: 55-69 years, 33% to 34% female) for the referral and procedure cohorts. There was geographic variation and a weak concordance between AF diagnoses, ablation referrals, and procedures (correlation coefficients 0.33-0.36). Increased material deprivation was associated with more AF diagnoses (rate ratio [RR]: 1.13), but fewer ablation referrals (RR: 0.49) and procedures (RR: 0.48). Increased residential instability was associated with more AF diagnoses (RR: 1.02), but fewer ablation referrals (RR: 0.63) and procedures (RR: 0.64). Higher ethnic concentration was associated with fewer AF diagnoses, ablation referrals, and procedures.

Conclusions

In a jurisdiction with universal health care, greater material deprivation and residential instability were associated with more AF diagnoses but less access to ablation, suggesting substantial social gradients in equitable access to AF care.

Investigating the independent and synergistic associations between neighbourhood greenness and physical activity in relation to perceived mental health among adults in Canada

The relationships among neighbourhood greenness, physical activity, and mental health are unclear; therefore, we examined the independent and synergistic associations between neighbourhood greenness and self-rated mental health among a nationally representative sample of urban-dwelling adults in Canada (18-79 years) from the 2007-2019 Canadian Health Measures Survey (n = 12,531). We assessed neighbourhood greenness using the Normalized Difference Vegetation Index within a 500-meter radius of participants' residential postal codes. We measured physical activity using accelerometers and determined adherence to the recommended 150-minutes of moderate-to-vigorous intensity physical activity (MVPA) per week. We used weighted logistic regression models to test whether MVPA guideline adherence was an effect modifier in the association between neighbourhood greenness and self-rated mental health, adjusting for individual and neighbourhood characteristics. Neighbourhood greenness (aOR = 0.89 [0.62, 1.29]) and MVPA adherence (aOR = 1.22 [0.89, 1.69]) were not associated with self-rated mental health, and no interaction were found on the additive (Relative Excess Risk Due to Interaction = -0.45 [-1.24, 0.35], Attributable Proportion = -0.38 [-1.02, 0.26], Synergy Index = 0.28 [0.02, 3.20]) or multiplicative (OR = 0.7 [0.4, 1.3]) scales. Engaging in the recommended amount of MVPA did not change the finding that Canadian adults had similar self-rated mental health regardless of their neighbourhood greenness.

Impact of Remoteness of Residence and Socioeconomic Status on Outcomes Among Children With Heart Disease in Alberta

Background

There is a paucity of data regarding the impact of remoteness of residence (RoR) and socioeconomic status (SES) on access to care and outcomes for children with congenital heart disease (CHD) or acquired heart disease (AHD) in a jurisdiction of universal health and centralized cardiac care.

Objectives

The primary objective was to examine whether RoR, SES, and their interaction impact access to health care and outcomes for children with heart disease in Alberta, Canada.

Methods

This was a population-based study of children with CHD or AHD born between January 1, 2005, and December 31, 2017, in Alberta, Canada. Primary outcomes included age at diagnosis, time from diagnosis to intervention, number of annual primary care visits, annual cardiologist visits, annual emergency room visits, and survival. Multivariable Cox proportional hazards models identified independent associations. Longitudinal relationships between the number of annual physician visits and RoR and SES were assessed with multivariable Poisson models.

Results

We included 12,542 children (94% CHD, 6% AHD), 70.4% living <60 minutes' drive of a cardiac center, and 10.9% residing >180 minutes away. RoR and SES were not associated with age at diagnosis, time from diagnosis to intervention, annual primary care visits, or transplant free survival for either CHD or AHD. Although SES demonstrated no impact, annual annual cardiologist visits were inversely related to RoR for CHD (60-180 minutes rate ratio [RR]: 0.83, 95% CI: 0.73-0.95; >180 minutes RR: 0.77, 95% CI: 0.67-0.88; P < 0.0001) and AHD (60-180 minutes RR: 0.63, 95% CI: 0.39-1.00; >180 minutes RR: 0.53, 95% CI: 0.34-0.84; P = 0.02). Additionally, increased annual emergency room visits were associated with further RoR (P < 0.001) in both CHD and AHD and lower SES (P < 0.001) only for those with CHD.

Conclusions

Age at diagnosis, time to intervention, annual primary care visits, and transplant-free all-cause survival were not impacted by RoR or SES in children with heart disease. Greater RoR and SES, however, were associated with fewer annual cardiology visits and increased annual emergency room visits, which highlights the need for novel surveillance strategies for remote pediatric patients with heart disease.

A multicriteria vulnerability index for equitable resource allocation in public health funding

SETTING

This paper describes an action research project with the Centre universitaire intégré de santé et de services sociaux - Capitale Nationale (CIUSSS-CN) who identified a need to assess vulnerability in their territories in order to ensure equitable distribution of the Integrated Perinatal and Early Childhood Services (SIPPE) program funds. The objective was to design and validate a multicriteria model to provide a more accurate portrait of vulnerability based on recent social realities.

INTERVENTION

Our multidisciplinary research team of 7 members included experts in analytics, decision aiding, and community and public health. In collaboration with 6 CIUSSS-CN professionals, we co-constructed, during 9 workshops, a multicriteria model to aggregate the multiple dimensions of vulnerability. We used a value-focused thinking approach and applied the method MACBETH assisted by a geographic information system.

OUTCOMES

Criteria, scales, and weights were validated and led to a vulnerability score for each CIUSSS-CN territory. This score provides a more accurate portrait of territorial disparities based on data and the participants' experience. The model was implemented in a dynamic user-friendly tool and serves to support decision-makers in the resource allocation process. Knowledge transfer was conducted during and after the process.

IMPLICATIONS

This multidisciplinary research has served to anchor public health funding in local realities, with an emphasis on equity and stakeholder engagement. Our mixed-method approach integrating qualitative and quantitative data is adaptable to other contexts. Our results can enhance intervention effectiveness and allow for a better response to the needs of the population targeted by the SIPPE program.

Exposure to ambient polycyclic aromatic hydrocarbons and early-onset female breast cancer in a case-control study in Ontario, Canada

Background

Ambient polycyclic aromatic hydrocarbons (PAHs) are a class of toxicologically important and understudied air pollutants. Epidemiologic evidence suggests that chronic exposure to PAHs increases breast cancer risk; however, there are few studies in nonoccupational settings that focus on early-onset diagnoses.

Methods

The relationship between residentially-based ambient PAH concentrations and female breast cancer, among those 18-45 years of age, was characterized in the Ontario Environment and Health Study (OEHS). The OEHS was a population-based case-control study undertaken in Ontario, Canada between 2013 and 2015. Primary incident breast cancers were identified within 3 months of diagnosis, and a population-based series of controls were recruited. Concentrations of ambient PAHs, using fluoranthene as a surrogate, were derived using a chemical transport model at a 2.5 km spatial resolution. These estimates were assigned to participants' residences at the time of the interview and 5 years prior. Logistic regression was used to estimate odds ratios (ORs) and their 95% confidence intervals (CIs) based on a quartile categorization of fluoranthene exposure while adjusting for a series of individual- and area-level risk factors. The shape of the exposure-response trend was evaluated using cubic splines.

Results

Median fluoranthene exposure for cases and controls was 0.0017 µg/m3 and 0.0014 µg/m3, respectively. In models adjusted for a parsimonious set of risk factors, the highest quartile of exposure was associated with an increased risk of breast cancer (OR = 2.16; 95% CI = 1.22, 3.84). Restricted spline analyses revealed nonlinear dose-response patterns.

Conclusions

These findings support the hypothesis that ambient PAH exposures increases the risk of early-onset breast cancer.

Residential exposure to ambient fine particulate matter (PM2.5) and nitrogen dioxide (NO2) and incident breast cancer among young women in Ontario, Canada

BACKGROUND

Air pollution has been classified as a human carcinogen based largely on findings for respiratory cancers. Emerging, but limited, evidence suggests that it increases the risk of breast cancer, particularly among younger women. We characterized associations between residential exposure to ambient fine particulate matter (PM2.5) and nitrogen dioxide (NO2) and breast cancer. Analyses were performed using data collected in the Ontario Environmental Health Study (OEHS).

METHODS

The OEHS, a population-based case-control study, identified incident cases of breast cancer in Ontario, Canada among women aged 18-45 between 2013 and 2015. A total of 465 pathologically confirmed primary breast cancer cases were identified from the Ontario Cancer Registry, while 242 population-based controls were recruited using random-digit dialing. Self-reported questionnaires were used to collect risk factor data and residential histories. Land-use regression and remote-sensing estimates of NO2 and PM2.5, respectively, were assigned to the residential addresses at interview, five years earlier, and at menarche. Logistic regression was used to estimate odds ratios (OR) and their 95 % confidence intervals (CI) in relation to an interquartile range (IQR) increase in air pollution, adjusting for possible confounders.

RESULTS

PM2.5 and NO2 were positively correlated with each other (r = 0.57). An IQR increase of PM2.5 (1.9 µg/m3) and NO2 (6.6 ppb) at interview residence were associated with higher odds of breast cancer and the adjusted ORs and 95 % CIs were 1.37 (95 % CI = 0.98-1.91) and 2.33 (95 % CI = 1.53-3.53), respectively. An increased odds of breast cancer was observed with an IQR increase in NO2 at residence five years earlier (OR = 2.16, 95 % CI: 1.41-3.31), while no association was observed with PM2.5 (OR = 0.96, 95 % CI 0.64-1.42).

CONCLUSIONS

Our findings support the hypothesis that exposure to ambient air pollution, especially those from traffic sources (i.e., NO2), increases the risk of breast cancer in young women.

Patient Factors Associated with 10-Year Survival After Arthroplasty for Hip Fracture: A Population-Based Study in Ontario, Canada

BACKGROUND

The aim of this study was to describe long-term (10-year) patient survival after arthroplasty for hip fracture and to determine what patient factors are associated with that outcome.

METHODS

We performed a retrospective cohort analysis of patients ≥60 years old who underwent either hemiarthroplasty or total hip arthroplasty for femoral neck fracture between 2002 and 2009. We used routinely collected, validated health-care databases linked through ICES (formerly known as the Institute for Clinical Evaluative Sciences). We estimated the association between baseline variables and survival 10 years post-fracture using Poisson regression. Restricted cubic spline functions modeled the probability of 10-year survival by age and tested whether there was an inflection point after which the probability of 10-year survival decreased more rapidly. We estimated 10-year survival probabilities for different patient groups.

RESULTS

There were 19,659 patients in the final cohort. Eighteen percent (3,564) of the patients were alive at 10 years postoperatively. Factors associated with a higher likelihood of 10-year survival included younger age, female sex (risk ratio [RR] = 1.56, 95% confidence interval [CI] = 1.46 to 1.68), lower American Society of Anesthesiologists (ASA) class (ASA I or II versus IV or V: RR = 1.96, 95% CI = 1.76 to 2.19), independent living status (RR = 2.68, 95% CI = 2.23 to 3.22), and fewer specific comorbidities. A threshold age of 73 years was the inflection point after which the probability of 10-year survival decreased more rapidly in females. Estimated 10-year survival probabilities ranged from 79.0% (95% CI = 75.5% to 82.5%) to 0.8% (95% CI = 0.6% to 1.0%).

CONCLUSIONS

Approximately 1 in 6 patients live at least 10 years following a hip fracture. This study identifies baseline characteristics that predict survival greater than 10 years, including an age of <75 years, an ASA class of I or II, and independent living status prior to the hip fracture. Results can inform discussions around treatment choices, anticipated outcomes, and the natural history of hip fractures.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Costs of Transfer From Nontrauma to Trauma Centers Among Patients With Minor Injuries

Importance

Nearly half the patients transferred from nontrauma centers to trauma centers have minor injuries, yet trauma center care is not associated with a difference in morality among patients with minor injuries. Consequently, reducing the frequency of such transfers has been postulated as a method to improve resource allocation. Currently, the economic implications of these transfers are not well understood.

Objective

To estimate health care costs associated with the transfer of patients with minor injuries from nontrauma to trauma centers.

Design, Setting, and Participants

This retrospective, population-based cohort study was conducted from April 1, 2009, to March 31, 2020, in Ontario, Canada. Participants included individuals aged 16 years or older who were transferred to a trauma center after presenting to a nontrauma center with a minor injury (survival >24 hours, Injury Severity Score [ISS] <16, and absence of an American College of Surgeons-defined critical injury). Statistical analysis was conducted from March 2022 to June 2024.

Main Outcomes and Measures

The main outcome was total health care costs within 30 days of injury, standardized to 2015 Canadian dollars (CAD$). Propensity scoring was used to match transferred patients with controls admitted to nontrauma centers. Negative binomial models were used to estimate differences in costs between transferred patients and matched controls.

Results

Of the 14 557 patients with minor injuries transferred to a trauma center (mean [SD] age, 48.1 [20.9] years; 5367 female patients [36.9%]; median ISS, 4 [IQR, 2-5]), 12 652 (86.9%) were matched with a control. Thirty days after injury, mean health care costs among transferred patients were CAD$13 540 (95% CI, CAD$13 319-CAD$13 765), a 6.5% (95% CI, 4.4%-8.5%) increase relative to controls (CAD$12 719 [95% CI, CAD$12 582-CAD$12 857]). Half the transferred patients (54.9% [7994 of 14 557]) were admitted, while the remainder were discharged after evaluation in the trauma center emergency department. Among patients admitted to a trauma center, mean 30-day costs were CAD$19 602 (95% CI, CAD$19 294-CAD$19 915), a 54.6% (95% CI, 51.5%-57.8%) increase relative to controls.

Conclusions and Relevance

This cohort study of patients with minor injuries transferred from nontrauma centers to trauma centers found that the transfer of these patients was associated with increased costs to the health care system. Given the high prevalence of such transfers, these findings suggest that the development of systems to support the care of patients with minor injuries at their local hospitals is essential to the sustainability of trauma systems.

Impact of structured multicentre enhanced recovery after surgery (ERAS) protocol implementation on length of stay after colorectal surgery

BACKGROUND

Increased length of stay after surgery is associated with increased healthcare utilization and adverse patient outcomes. While enhanced recovery after surgery (ERAS) protocols have been shown to reduce length of stay after colorectal surgery in trial settings, their effectiveness in real-world settings is more uncertain. The aim of this study was to assess the impact of ERAS protocol implementation on length of stay after colorectal surgery, using real-world data.

METHODS

In 2012, ERAS protocols were introduced at 15 Ontario hospitals as part of the iERAS study. A cohort of patients undergoing colorectal surgery treated at these hospitals between 2008 and 2019 was created using health administrative data. Mean length of stay was computed for the intervals before and after ERAS implementation. Interrupted time series analyses were performed for predefined subgroups, namely all colorectal surgery, colorectal surgery without complications, right-sided colorectal surgery, and left-sided colorectal surgery. Sensitivity analyses were then conducted using adjusted length of stay, accounting for length of stay predictors, including: patient age, sex, marginalization, co-morbidities, and diagnosis; surgeon volume of cases, years in practice, and colorectal surgery expertise; hospital volume; and other contextual factors, including procedure type and timing, surgical approach, and in-hospital complications.

RESULTS

A total of 32 612 patients underwent colorectal surgery during the study interval. ERAS implementation led to a decrease in length of stay of 1.05 days (13.7%). Larger decreases in length of stay were seen with more complex surgeries, with a level change of 1.17 days (15.6%) noted for the subgroup of patients undergoing left-sided colorectal surgery. The observed decreases in length of stay were durable for the length of the study interval in all analyses. When adjusting for predictors of length of stay, the effect of ERAS implementation on length of stay was larger (reduction of 1.46 days).

CONCLUSION

Introducing formal ERAS protocols reduces length of stay after colorectal surgery significantly, independent of temporal trends toward decreasing length of stay. These effects are durable, demonstrating that ERAS protocol implementation is an effective hospital-level intervention to reduce length of stay after colorectal surgery.

Prescription Medication Use in Pregnancy in People with Disabilities: A Population-Based Cohort Study

Background: Individuals with disabilities may require specific medications in pregnancy. The prevalence and patterns of medication use, overall and for medications with known teratogenic risks, are largely unknown. Methods: This population-based cohort study in Ontario, Canada, 2004-2021, comprised all recognized pregnancies among individuals eligible for public drug plan coverage. Included were those with a physical (n = 44,136), sensory (n = 13,633), intellectual or developmental (n = 2,446) disability, or multiple disabilities (n = 5,064), compared with those without a disability (n = 299,944). Prescription medication use in pregnancy, overall and by type, was described. Modified Poisson regression generated relative risks (aRR) for the use of medications with known teratogenic risks and use of ≥2 and ≥5 medications concurrently in pregnancy, comparing those with versus without a disability, adjusting for sociodemographic and clinical factors. Results: Medication use in pregnancy was more common in people with intellectual or developmental (82.1%), multiple (80.4%), physical (73.9%), and sensory (71.9%) disabilities, than in those with no known disability (67.4%). Compared with those without a disability (5.7%), teratogenic medication use in pregnancy was especially higher in people with multiple disabilities (14.2%; aRR 2.03, 95% confidence interval [CI]: 1.88-2.20). Furthermore, compared with people without a disability (3.2%), the use of ≥5 medications concurrently was more common in those with multiple disabilities (13.4%; aRR 2.21, 95% CI: 2.02-2.41) and an intellectual or developmental disability (9.3%; aRR 2.13, 95% CI: 1.86-2.45). Interpretation: Among people with disabilities, medication use in pregnancy is prevalent, especially for potentially teratogenic medications and polypharmacy, highlighting the need for preconception counseling/monitoring to reduce medication-related harm in pregnancy.

The association between off- and on-premise alcohol outlet density and 100% alcohol-attributable emergency department visits by neighbourhood-level socioeconomic status in Ontario, Canada

Alcohol availability is positively associated with alcohol use and harms, but the influence of socioeconomic status (SES) on these associations is not well established. This population-based cross-sectional study examined neighbourhood-level associations between physical alcohol availability (measured as off- and on-premise alcohol outlet density) and 100% alcohol-attributable emergency department (ED) visits by neighbourhood SES in Ontario, Canada from 2017 to 2019 (n = 19,740). A Bayesian spatial modelling approach was used to assess associations and account for spatial autocorrelation, which produced risk ratios (RRs) and 95% credible intervals (95% CrI). Each additional off-premise alcohol outlet in a neighbourhood was associated with a 3% increased risk of alcohol-attributable ED visits in both men (RR = 1.03, 95%CrI: 1.02-1.04) and women (RR = 1.03, 95% CrI: 1.02-1.04). Positive associations were also observed between on-premise alcohol outlet density and alcohol-attributable ED visits, although effect sizes were small. A disproportionately greater association with ED visits was observed with increasing alcohol outlet density in the lowest compared to higher SES neighbourhoods. Reducing physical alcohol availability may be an important policy lever for reducing alcohol harm and alcohol-attributable health inequities.

Small area variations in non-affective first-episode psychosis: the role of socioeconomic and environmental factors

BACKGROUND

There is strong evidence supporting the association between environmental factors and increased risk of non-affective psychotic disorders. However, the use of sound statistical methods to account for spatial variations associated with environmental risk factors, such as urbanicity, migration, or deprivation, is scarce in the literature.

METHODS

We studied the geographical distribution of non-affective first-episode psychosis (NA-FEP) in a northern region of Spain (Navarra) during a 54-month period considering area-level socioeconomic indicators as putative explanatory variables. We used several Bayesian hierarchical Poisson models to smooth the standardized incidence ratios (SIR). We included neighborhood-level variables in the spatial models as covariates.

RESULTS

We identified 430 NA-FEP cases over a 54-month period for a population at risk of 365,213 inhabitants per year. NA-FEP incidence risks showed spatial patterning and a significant ecological association with the migrant population, unemployment, and consumption of anxiolytics and antidepressants. The high-risk areas corresponded mostly to peripheral urban regions; very few basic health sectors of rural areas emerged as high-risk areas in the spatial models with covariates.

DISCUSSION

Increased rates of unemployment, the migrant population, and consumption of anxiolytics and antidepressants showed significant associations linked to the spatial-geographic incidence of NA-FEP. These results may allow targeting geographical areas to provide preventive interventions that potentially address modifiable environmental risk factors for NA-FEP. Further investigation is needed to understand the mechanisms underlying the associations between environmental risk factors and the incidence of NA-FEP.

A synthetic vulnerable population dataset for fine scale geographical equity analysis and urban planning

Assessing the social and economic vulnerability of populations within a given area is essential for conducting environmental equity evaluations and devising effective public policies to mitigate disparities. However, prevailing indicators used to measure socio-economic vulnerability exhibit several shortcomings. Primarily relying on factor analysis, these indicators face challenges in terms of comparability over time, lack of standardized scales, and inherent limitations associated with composite indicators. To address these shortcomings, we propose a novel approach that estimates the number of potentially vulnerable individuals by constructing a synthetic population. Our methodology, developed using open tools and datasets, offers a scalable solution applicable to the entire Canadian context. The resulting percentage of potentially vulnerable populations demonstrates strong correlations with traditional vulnerability indicators commonly used in Canada, while overcoming their inherent limitations. The generated dataset holds significant potential and serves as a valuable resource for both researchers and governmental organizations. It provides a robust foundation for conducting equity analyses, assessments, and policy evaluations, thereby facilitating evidence-based decision-making processes aimed at promoting social and economic inclusivity.

EXploring Patterns of Use and Effects of Adult Day Programs to Improve Trajectories of Continuing Care (EXPEDITE): Protocol for a Retrospective Cohort Study

BACKGROUND

Adult day programs provide critical supports to older adults and their family or friend caregivers. High-quality care in the community for as long as possible and minimizing facility-based continuing care are key priorities of older adults, their caregivers, and health care systems. While most older adults in need of care live in the community, about 10% of newly admitted care home residents have relatively low care needs that could be met in the community with the right supports. However, research on the effects of day programs is inconsistent. The methodological quality of studies is poor, and we especially lack robust, longitudinal research.

OBJECTIVE

Our research objectives are to (1) compare patterns of day program use (including nonuse) by province (Alberta, British Columbia, and Manitoba) and time; (2) compare characteristics of older adults by day program use pattern (including nonuse), province, and time; and (3) assess effects of day programs on attendees, compared with a propensity score-matched cohort of older nonattendees in the community.

METHODS

In this population-based retrospective cohort study, we will use clinical and health administrative data of older adults (65+ years of age) who received publicly funded continuing care in the community in the Canadian provinces of Alberta, British Columbia, and Manitoba between January 1, 2012, and December 31, 2024. We will compare patterns of day program use between provinces and assess changes over time. We will then compare characteristics of older adults (eg, age, sex, physical or cognitive disability, area-based deprivation indices, and caregiver availability or distress) by pattern of day program use or nonuse, province, and time. Finally, we will create a propensity score-matched comparison group of older adults in the community, who have not attended a day program. Using time-to-event models and general estimating equations, we will assess whether day program attendees compared with nonattendees enter care homes later; use emergency, acute, or primary care less frequently; experience less cognitive and physical decline; and have better mental health.

RESULTS

This will be a 3-year study (July 1, 2024, to June 30, 2027). We received ethics approvals from the relevant ethics boards. Starting on July 1, 2024, we will work with the 3 provincial health systems on data access and linkage, and we expect data analyses to start in early 2025.

CONCLUSIONS

This study will generate robust Canadian evidence on the question whether day programs have positive, negative, or no effects on various older adult and caregiver outcomes. This will be a prerequisite to improving the quality of care provided to older adults in day programs, ultimately improving the quality of life of older adults and their caregivers.

TRIAL REGISTRATION

ClinicalTrials.gov NCT06440447; https://clinicaltrials.gov/study/NCT06440447.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

PRR1-10.2196/60896.

Epidemiology of Hepatitis C over 28 years of monitoring Canadian blood donors: Insight into a low-risk undiagnosed population

BACKGROUND

Hepatitis C is a blood-borne infection with the hepatitis C virus (HCV) that can progress to cirrhosis and liver cancer. About 70% (50-80%) of infections become chronic and exhibit anti-HCV and HCV nucleic acid (NAT) positivity. Direct acting oral pan genotypic antiviral treatment became available in 2014 and was free for most Canadians in 2018. Clinical screening for HCV infection is risk-based. About 1% of Canadians have been infected with HCV, with 0.5% chronically infected (about 25% unaware) disproportionately impacting marginalized groups. Blood donors are in good health, are deferred for risks such as injection drug use and can provide insight into the low-risk undiagnosed population. Here we describe HCV epidemiology in first-time blood donors over 28 years of monitoring.

METHODS

All first-time blood donors in all Canadian provinces except Quebec (1993 to 2021) were analyzed. All blood donations were tested for HCV antibodies (anti-HCV) and since late 1999 also HCV NAT. A case-control study was also included. All HCV positive donors (cases) since 2005 and HCV negative donors (1:4 ratio controls) matched for age, sex and location were invited to complete a risk factor interview. Separate logistic regression models for anti-HCV positivity and chronic HCV assessed the association between age cohort, sex, region and neighbourhood material deprivation and ethnocultural concentration.

CASE

control data were analysed by logistic regression.

RESULTS

There were 2,334,238 donors from 1993 to 2021 included. Prevalence for anti-HCV was 0.33% (0.30,0.37) in 1993 and 0.07% (0.05,0.09) in 2021 (p < 0.0001). In 2021 0.03% (0.01,0.04) had chronic HCV. Predictors for both anti-HCV positivity and chronic HCV were similar, for chronic HCV were male sex (OR 1.8, 1.6,2.1), birth between 1945 and 1975 (OR 7.1, 5.9,8.5), living in the western provinces (OR 1.4, 1.2,1.7) and living in material deprived (OR 2.7, 2.1,3.5) and more ethnocultural concentrated neighbourhoods (OR 1.8, 1.3,2.5). There were 318 (35.4%) of chronic HCV positive and 1272 (39.6%) of controls who participated in case control interviews. The strongest risks for acquisition were injection drug use (OR 96.9, 22.3,420.3) and birth in a high prevalence country (OR 24.5, 11.2,53.6).

CONCLUSIONS

Blood donors have 16 times lower HCV prevalence then the general population. Donors largely mirror population trends and highlight the ongoing prevalence of untreated infections in groups without obvious risks for acquisition missed by risk-based patient screening.

Impact of Location of Residence and Distance to Cancer Centre on Medical Oncology Consultation and Neoadjuvant Chemotherapy for Triple-Negative and HER2-Positive Breast Cancer

Despite consensus guidelines, most patients with early-stage triple-negative (TN) and HER2-positive (HER2+) breast cancer do not see a medical oncologist prior to surgery and do not receive neoadjuvant chemotherapy (NAC). To understand barriers to care, we aimed to characterize the relationship between geography (region of residence and cancer centre proximity) and receipt of a pre-treatment medical oncology consultation and NAC for patients with TN and HER2+ breast cancer. Using linked administrative datasets in Ontario, Canada, we performed a retrospective population-based analysis of women diagnosed with stage I-III TN or HER2+ breast cancer from 2012 to 2020. The outcomes were a pre-treatment medical oncology consultation and the initiation of NAC. We created choropleth maps to assess the distribution of the outcomes and cancer centres across census divisions. To assess the relationship between distance to the nearest cancer centre and outcomes, we performed multivariable regression analyses adjusted for relevant factors, including tumour extent and nodal status. Of 14,647 patients, 29.9% received a pre-treatment medical oncology consultation and 77.7% received NAC. Mapping demonstrated high interregional variability, ranging across census divisions from 12.5% to 64.3% for medical oncology consultation and from 8.8% to 64.3% for NAC. In the full cohort, compared to a distance of ≤5 km from the nearest cancer centre, only 10-25 km was significantly associated with lower odds of NAC (OR 0.83, 95% CI 0.70-0.99). Greater distances were not associated with pre-treatment medical oncology consultation. The interregional variability in medical oncology consultation and NAC for patients with TN and HER2+ breast cancer suggests that regional and/or provider practice patterns underlie discrepancies in the referral for and receipt of NAC. These findings can inform interventions to improve equitable access to NAC for eligible patients.

Epidemiological studies likely need to consider PM2.5 composition even if total outdoor PM2.5 mass concentration is the exposure of interest

Background

Outdoor fine particulate air pollution, <2.5 µm (PM2.5) mass concentrations can be constructed through many different combinations of chemical components that have varying levels of toxicity. This poses a challenge for studies interested in estimating the health effects of total outdoor PM2.5 (i.e., how much PM2.5 mass is present in the air regardless of composition) because we must consider possible confounders of the version of treatment-outcome relationships.

Methods

We evaluated the extent of possible bias in mortality hazard ratios for total outdoor PM2.5 by examining models with and without adjustment for sulfate and nitrate in PM2.5 as examples of potential confounders of version of treatment-outcome relationships. Our study included approximately 3 million Canadians and Cox proportional hazard models were used to estimate hazard ratios for total outdoor PM2.5 adjusting for sulfate and/or nitrate and other relevant covariates.

Results

Hazard ratios for total outdoor PM2.5 and nonaccidental, cardiovascular, and respiratory mortality were overestimated due to the confounding version of treatment-outcome relationships, and associations for lung cancer mortality were underestimated. Sulfate was most strongly associated with nonaccidental, cardiovascular, and respiratory mortality suggesting that regulations targeting this specific component of outdoor PM2.5 may have greater health benefits than interventions targeting total PM2.5.

Conclusions

Studies interested in estimating the health impacts of total outdoor PM2.5 (i.e., how much PM2.5 mass is present in the air) need to consider potential confounders of the version of treatment-outcome relationships. Otherwise, health risk estimates for total PM2.5 will reflect some unknown combination of how much PM2.5 mass is present in the air and the kind of PM2.5 mass that is present.

Disparities in Access to a Regular Primary Care Physician Among First-Generation Migrants with Early Psychosis in Ontario, Canada

Disparities in primary care utilization among migrants with early psychosis may be related to lack of access to a regular primary care physician. This study aimed to investigate access to a regular primary care physician among first-generation migrants with early psychosis. People aged 14-35 years with first onset non-affective psychotic disorder in Ontario, Canada were identified in health administrative data (N = 39,440). Access to a regular primary care physician through enrollment in the year prior to diagnosis was compared between first-generation migrants (categorized by country of birth) and the general population using modified Poisson regression. Most migrant groups had a lower prevalence of regular primary care physician access relative to the general population, particularly migrants from Africa (African migrants: 81% vs. non-migrants: 89%). Adjustment for sociodemographic and clinical factors attenuated these differences, although the disparities for migrants from Africa remained (PR = 0.96, 95%CI = 0.94-0.99). Interventions aimed at improving primary care physician access in migrant groups may facilitate help-seeking and improve pathways to care in early psychosis.

Neighborhood-Level Burden of Social Risk Factors on Respiratory Syncytial Virus Hospitalization in Ontario, Canada, 2016-2019

Background

Beyond clinical risk factors, little is known about the impact of social determinants on respiratory syncytial virus (RSV) burden. Our study aimed to estimate RSV-related hospitalization rates across sociodemographic and housing characteristics.

Methods

We conducted a population-based study of all RSV-related hospitalizations in Ontario, Canada, between September 1, 2016, and August 31, 2019, using validated hospital discharge codes and census data. Crude and age-standardized annualized RSV incidence rates and rate ratios (RRs) were estimated for a range of individual-level demographics and neighborhood-level measures of marginalization and housing characteristics.

Results

Overall, the annual RSV-related hospitalization rate was 27 per 100 000, with the highest rates observed in children age <12 months (1049 per 100 000) and 12-23 months (294 per 100 000) and adults age ≥85 years (155 per 100 000). Higher RSV-related hospitalization rates were associated with increasing marginalization quintile (Q) of material resources (RR, 1.4; Q5: 33 per 100 000 vs Q1: 24 per 100 000) and household instability (RR, 1.5; Q5: 31 per 100 000 vs Q1: 22 per 100 000).

Conclusions

The burden of RSV-related hospitalization was greatest in young children and older adults, with variation by sociodemographic and housing factors. Understanding the role of these social factors is crucial for informing equitable preventive program delivery.

Ambient polycyclic aromatic hydrocarbon exposure and breast cancer risk in a population-based Canadian case-control study

PURPOSE

Polycyclic aromatic hydrocarbons (PAHs) represent a class of ubiquitous pollutants recognized as established human carcinogens and endocrine-disrupting chemicals. PAHs have seldom been modeled at the population-level in epidemiological studies. Fluoranthene is a prevalent PAH in urban settings and correlates with the occurrence of other PAHs. The purpose of this study was to evaluate associations between long-term residential exposure to ambient PAHs and breast cancer risk, both pre- and post-menopausal, in Canada.

METHODS

Using the National Enhanced Cancer Surveillance System (NECSS), a national-scale Canadian population-based case-control study, annual fluoranthene exposures were estimated using the GEM-MACH-PAH chemical transport model on the basis of geocoded residential histories throughout a 20-year exposure window. Odds ratios (ORs) and 95% confidence intervals (CIs) controlling for potential confounders were estimated using logistic regression. Separate analyses were conducted for Ontario and national samples given a finer-resolution exposure surface and additional risk factor information available for Ontario.

RESULTS

Positive associations were observed between fluoranthene exposure and premenopausal breast cancer, with inconsistent findings for postmenopausal breast cancer. For premenopausal breast cancer, adjusted ORs of 2.48 (95% CI: 1.29, 4.77) and 1.59 (95% CI: 1.11, 2.29) were observed when comparing the second highest category of exposure to the lowest, among the Ontario and national samples, respectively. For postmenopausal breast cancer, adjusted ORs were 1.10 (95% CI: 0.67, 1.80) and 1.33 (95% CI: 1.02, 1.73). Associations for the highest level of exposure, across both samples and menopausal strata, were non-significant.

CONCLUSION

This study provides support for the hypothesis that ambient PAH exposures increase the risk of premenopausal breast cancer.

Cost Evaluation of the Ontario Virtual Urgent Care Pilot Program: Population-Based, Matched Cohort Study

BACKGROUND

In 2020, the Ministry of Health (MoH) in Ontario, Canada, introduced a virtual urgent care (VUC) pilot program to provide alternative access to urgent care services and reduce the need for in-person emergency department (ED) visits for patients with low acuity health concerns.

OBJECTIVE

This study aims to compare the 30-day costs associated with VUC and in-person ED encounters from an MoH perspective.

METHODS

Using administrative data from Ontario (the most populous province of Canada), a population-based, matched cohort study of Ontarians who used VUC services from December 2020 to September 2021 was conducted. As it was expected that VUC and in-person ED users would be different, two cohorts of VUC users were defined: (1) those who were promptly referred to an ED by a VUC provider and subsequently presented to an ED within 72 hours (these patients were matched to in-person ED users with any discharge disposition) and (2) those seen by a VUC provider with no referral to an in-person ED (these patients were matched to patients who presented in-person to the ED and were discharged home by the ED physician). Bootstrap techniques were used to compare the 30-day mean costs of VUC (operational costs to set up the VUC program plus health care expenditures) versus in-person ED care (health care expenditures) from an MoH perspective. All costs are expressed in Canadian dollars (a currency exchange rate of CAD $1=US $0.76 is applicable).

RESULTS

We matched 2129 patients who presented to an ED within 72 hours of VUC referral and 14,179 patients seen by a VUC provider without a referral to an ED. Our matched populations represented 99% (2129/2150) of eligible VUC patients referred to the ED by their VUC provider and 98% (14,179/14,498) of eligible VUC patients not referred to the ED by their VUC provider. Compared to matched in-person ED patients, 30-day costs per patient were significantly higher for the cohort of VUC patients who presented to an ED within 72 hours of VUC referral ($2805 vs $2299; difference of $506, 95% CI $139-$885) and significantly lower for the VUC cohort of patients who did not require ED referral ($907 vs $1270; difference of $362, 95% CI 284-$446). Overall, the absolute 30-day costs associated with the 2 VUC cohorts were $18.9 million (ie, $6.0 million + $12.9 million) versus $22.9 million ($4.9 million + $18.0 million) for the 2 in-person ED cohorts.

CONCLUSIONS

This costing evaluation supports the use of VUC as most complaints were addressed without referral to ED. Future research should evaluate targeted applications of VUC (eg, VUC models led by nurse practitioners or physician assistants with support from ED physicians) to inform future resource allocation and policy decisions.

Associations of neighborhood greenspace, and active living environments with autism spectrum disorders: A matched case-control study in Ontario, Canada

BACKGROUND

Increasing evidence links early life residential exposure to natural urban environmental attributes and positive health outcomes in children. However, few studies have focused on their protective effects on the risk of autism spectrum disorder (ASD). The aim of this study was to investigate the associations of neighborhood greenspace, and active living environments during pregnancy with ASD in young children (≤6 years).

METHODS

We conducted a population-based matched case-control study of singleton term births in Ontario, Canada for 2012-2016. The ASD and environmental data was generated using the Ontario Autism Spectrum Profile, the Better Outcomes Registry & Network Ontario, and Canadian Urban Environmental Health Research Consortium. We employed conditional logistic regressions to estimate the odds ratio (OR) between ASD and environmental factors characterizing selected greenspace metrics and neighborhoods conducive to active living (i.e., green view index (GVI), normalized difference vegetation index (NDVI), tree canopy, park proximity and active living environments index (ALE)).

RESULTS

We linked 8643 mother-child pairs, including 1554 cases (18%). NDVI (OR 1.034, 0.944-1.024, per Inter Quartile Range [IQR] = 0.08), GVI (OR 1.025, 95% CI 0.953-1.087, per IQR = 9.45%), tree canopy (OR 0.992, 95% CI 0.903-1.089, per IQR = 6.24%) and the different categories of ALE were not associated with ASD in adjusted models for air pollution. In contrast, living closer to a park was protective (OR 0.888, 0.833-0.948, per 0.06 increase in park proximity index), when adjusted for air pollution.

CONCLUSIONS

This study reported mixed findings showing both null and beneficial effects of green spaces and active living environments on ASD. Further investigations are warranted to elucidate the role of exposure to greenspaces and active living environments on the development of ASD.

Mental health is positively associated with biodiversity in Canadian cities

Cities concentrate problems that affect human well-being and biodiversity. Exploring the link between mental health and biodiversity can inform more holistic public health and urban planning. Here we examined associations between bird and tree species diversity estimates from eBird community science datasets and national forest inventories with self-rated mental health metrics from the Canadian Community Health Survey. We linked data across 36 Canadian Metropolitan Areas from 2007-2022 at a postal code level. After controlling for covariates, we found that bird and tree species diversity were significantly positively related to good self-reported mental health. Living in a postal code with bird diversity one standard deviation higher than the mean increased reporting of good mental health by 6.64%. Postal codes with tree species richness one standard deviation more than the mean increased reporting of good mental health by 5.36%. Our results suggest that supporting healthy urban ecosystems may also benefit human well-being.

Adolescent Health Care Needs and Relationship to Disease in Patients With Childhood-Onset Systemic Lupus Erythematosus

OBJECTIVE

Our objective was to characterize adolescent health and psychosocial issues in patients with childhood-onset systemic lupus erythematosus (cSLE) and evaluate demographic and disease characteristics associated with adolescent health.

METHODS

We retrospectively examined adolescents aged 12 to 18 years with cSLE seen at the Hospital for Sick Children meeting the American College of Rheumatology/Systemic Lupus International Collaborating Clinics classification criteria, assessed by adolescent medicine in the cSLE clinic between 2018 and 2020. Adolescent health issues were characterized using the Home, Education/Employment, Activities, Diet/Drugs, Sexuality, Suicide/mood (HEADDSS) framework. Issues were classified as presenting and/or identified; adolescent health burden was tabulated as the number of distinct adolescent issues per patient. Multiple Poisson regression models examined associations between patient and disease characteristics (age, sex, material deprivation, disease activity, disease damage, and high-dose glucocorticoid exposure) and adolescent health issues.

RESULTS

A total of 108 (60%) of 181 adolescents with cSLE were seen by adolescent medicine, with a median of 2 (interquartile range [IQR] 1-3) visits and a median of 2 (IQR 1-5) adolescent health issues during the study period. Common issues were mood (presenting in 21% vs identified in 50%), sleep (27% vs 2%), school and education (26% vs 1%), and nonadherence (23% vs 8%). Psychoeducation was provided by adolescent medicine to 54% of patients. High-dose glucocorticoids (risk ratio [RR] 1.82, 95% confidence interval [CI] 1.41-2.35, P < 0.001), material deprivation (RR 1.17, 95% CI 1.04-1.30, P = 0.007), and lower SLE Disease Activity Index scores (RR 0.95, 95% CI 0.92-0.98, P = 0.004) were associated with higher adolescent health burden.

CONCLUSION

Adolescents with cSLE experience many adolescent issues, especially low mood. High-dose glucocorticoids and social marginalization are associated with greater adolescent health burden. This study highlights the importance of addressing adolescent health needs as part of routine care.

Predictors of 30-day recurrent emergency department visits for hyperglycemia in patients with types 1 and 2 diabetes: a population-based cohort study

OBJECTIVES

This study's aims were to describe the outcomes of patients with diabetes presenting with their first ED visit for hyperglycemia, and to identify predictors of recurrent ED visits for hyperglycemia.

METHODS

Using linked databases, we conducted a population-based cohort study of adult and pediatric patients with types 1 and 2 diabetes presenting with a first ED visit for hyperglycemia from April 2010 to March 2020 in Ontario, Canada. We determined the proportion of patients with a recurrent ED visit for hyperglycemia within 30 days of the index visit. Using multivariable regression analysis, we examined clinical and socioeconomic predictors for recurrent visits.

RESULTS

There were 779,632 patients with a first ED visit for hyperglycemia. Mean (SD) age was 64.3 (15.2) years; 47.7% were female. 11.0% had a recurrent visit for hyperglycemia within 30 days. Statistically significant predictors of a recurrent visit included: male sex, type 1 diabetes, regions with fewer visible minority groups and with less education or employment, higher hemoglobin A1C, more family physician or internist visits within the past year, being rostered to a family physician, previous ED visits in the past year, ED or hospitalization within the previous 14 days, access to homecare services, and previous hyperglycemia encounters in the past 5 years. Alcoholism and depression or anxiety were positive predictors for the 18-65 age group.

CONCLUSIONS

This population-level study identifies predictors of recurrent ED visits for hyperglycemia, including male sex, type 1 diabetes, regions with fewer visible minority groups and with less education or employment, higher hemoglobin A1C, higher previous healthcare system utilization (ED visits and hospitalization) for hyperglycemia, being rostered to a family physician, and access to homecare services. Knowledge of these predictors may be used to develop targeted interventions to improve patient outcomes and reduce healthcare system costs.

Residential surrounding greenness and the incidence of childhood asthma: Findings from a population-based cohort in Ontario, Canada

Several epidemiological studies have investigated the possible role that living in areas with greater amounts of greenspace has on the incidence of childhood asthma. These findings have been inconsistent, and few studies explored the relevance of timing of exposure. We investigated the role of residential surrounding greenness on the risk of incident asthma using a population-based retrospective cohort study. We included 982,131 singleton births in Ontario, Canada between 2006 and 2013. Two measures of greenness, the Normalized Difference Vegetation Index (NDVI) and the Green View Index (GVI), were assigned to the residential histories of these infants from pregnancy through to 12 years of age. Longitudinally-based diagnoses of asthma were determined by using provincial administrative health data. The extended Cox hazards model was used to characterize associations between greenness measures and asthma (up to age 12 years) while adjusting for several risk factors. In a fully adjusted model, that included a term for traffic-related air pollution (NO2), we found no association between an interquartile range increase (0.08) of the NDVI during childhood and asthma incidence (HR = 0.99; 95 % CI = 0.99-1.01). In contrast, we found that an 0.08 increase in NDVI during childhood reduced the risk of asthma in children 7-12 years of age by 14 % (HR = 0.86, 95 % CI:0.79-0.95). Seasonal differences in the association between greenness and asthma were noted. Our findings suggest that residential proximity to greenness reduces the risk of asthma in children aged 7-12.

Association between immigration status and total knee arthroplasty outcomes in Ontario, Canada: a population-based matched cohort study

BACKGROUND

Immigrants and refugees face unique challenges navigating the health care system to manage severe arthritis, because of unfamiliarity, lack of awareness of surgical options, or access. The purpose of this study was to assess total knee arthroplasty (TKA) uptake, surgical outcomes, and hospital utilization among immigrants and refugees compared with Canadian-born patients.

METHODS

We included all adults undergoing primary TKA from January 2011 to December 2020 in Ontario. Cohorts were defined as Canadian-born or immigrants and refugees. We assessed change in yearly TKA utilization for trend. We compared differences in 1-year revision, infection rates, 30-day venous thromboembolism (VTE), presentation to emergency department, and hospital readmission between matched Canadian-born and immigrant and refugee groups.

RESULTS

We included 158 031 TKA procedures. A total of 11 973 (7.6%) patients were in the immigrant and refugee group, and 146 058 (92.4%) patients were in the Canadian-born group. The proportion of TKAs in Ontario performed among immigrants and refugees nearly doubled over the 10-year study period (p < 0.001). After matching, immigrants were at relatively lower risk of 1-year revision (0.9% v. 1.6%, p < 0.001), infection (p < 0.001), death (p = 0.004), and surgical complications (p < 0.001). No differences were observed in rates of 30-day VTE or length of hospital stay. Immigrants were more likely to be discharged to rehabilitation (p < 0.001) and less likely to present to the emergency department (p < 0.001) than Canadian-born patients.

CONCLUSION

Compared with Canadian-born patients, immigrants and refugees have favourable surgical outcomes and similar rates of resource utilization after TKA. We observed an underutilization of these procedures in Ontario relative to their proportion of the population. This may reflect differences in perceptions of chronic pain or barriers accessing arthroplasty.

Characteristics of primary care practices by proportion of patients unvaccinated against SARS-CoV-2: a cross-sectional cohort study

BACKGROUND

Variations in primary care practices may explain some differences in health outcomes during the COVID-19 pandemic. We sought to evaluate the characteristics of primary care practices by the proportion of patients unvaccinated against SARS-CoV-2.

METHODS

We conducted a population-based, cross-sectional cohort study using linked administrative data sets in Ontario, Canada. We calculated the percentage of patients unvaccinated against SARS-CoV-2 enrolled with each comprehensive-care family physician, ranked physicians according to the proportion of patients unvaccinated, and identified physicians in the top 10% (v. the other 90%). We compared characteristics of family physicians and their patients in these 2 groups using standardized differences.

RESULTS

We analyzed 9060 family physicians with 10 837 909 enrolled patients. Family physicians with the largest proportion (top 10%) of unvaccinated patients (n = 906) were more likely to be male, to have trained outside of Canada, to be older, and to work in an enhanced fee-for-service model than those in the remaining 90%. Vaccine coverage (≥ 2 doses of SARS-CoV-2 vaccine) was 74% among patients of physicians with the largest proportion of unvaccinated patients, compared with 87% in the remaining patient population. Patients in the top 10% group tended to be younger and live in areas with higher levels of ethnic diversity and immigration and lower incomes.

INTERPRETATION

Primary care practices with the largest proportion of patients unvaccinated against SARS-CoV-2 served marginalized communities and were less likely to use team-based care models. These findings can guide resource planning and help tailor interventions to integrate public health priorities within primary care practices.

Early life exposure to pollens and increased risks of childhood asthma: a prospective cohort study in Ontario children

Asthma is a disease characterised by wheeze, cough and shortness of breath, and constitutes the most prevalent chronic disease among children [1]. Various phenotypes have been specifically identified in the paediatric population, and include early transient wheeze, current wheeze/asthma, and mild or moderate asthma [2]. Lifestyle behaviours, genetics, maternal and paternal factors, and environment exposures have been identified as risk factors in the multifactorial aetiology of childhood asthma [3].

Increased exposure to tree canopy around the place of residence at birth prevented the risk of childhood asthma development, but this protective effect can be reduced when exposure to weed and tree pollen increases https://bit.ly/3Tboabo

Sociodemographic Factors and Trends in Bronchiolitis-Related Emergency Department Visit and Hospitalization Rates

Importance

Bronchiolitis is the most common and most cumulatively expensive condition in pediatric hospital care. Few population-based studies have examined health inequalities in bronchiolitis outcomes over time.

Objective

To examine trends in bronchiolitis-related emergency department (ED) visit and hospitalization rates by sociodemographic factors in a universally funded health care system.

Design, Setting, and Participants

This repeated cross-sectional cohort study was performed from April 1, 2004, to March 31, 2022, using population-based health administrative data from children younger than 2 years in Ontario, Canada.

Main Outcome and Measures

Bronchiolitis ED visit and hospitalization rates per 1000 person-years reported for the equity stratifiers of sex, residence location (rural vs urban), and material resources quintile. Trends in annual rates by equity stratifiers were analyzed using joinpoint regression and estimating the average annual percentage change (AAPC) with 95% CI and the absolute difference in AAPC with 95% CI from April 1, 2004, to March 31, 2020.

Results

Of 2 921 573 children included in the study, 1 422 088 (48.7%) were female and 2 619 139 (89.6%) lived in an urban location. Emergency department visit and hospitalization rates were highest for boys, those with rural residence, and those with least material resources. There were no significant between-group absolute differences in the AAPC in ED visits per 1000 person-years by sex (female vs male; 0.22; 95% CI, -0.92 to 1.35; P = .71), residence (rural vs urban; -0.31; 95% CI -1.70 to 1.09; P = .67), or material resources (quintile 5 vs 1; -1.17; 95% CI, -2.57 to 0.22; P = .10). Similarly, there were no significant between-group absolute differences in the AAPC in hospitalizations per 1000 person-years by sex (female vs male; 0.53; 95% CI, -1.11 to 2.17; P = .53), residence (rural vs urban; -0.62; 95% CI, -2.63 to 1.40; P = .55), or material resources (quintile 5 vs 1; -0.93; 95% CI -3.80 to 1.93; P = .52).

Conclusions and Relevance

In this population-based cohort study of children in a universally funded health care system, inequalities in bronchiolitis ED visit and hospitalization rates did not improve over time.

The impact of referring hospital resources on interfacility overtriage: A population-based analysis

BACKGROUND

Nearly half of patients transferred from non-trauma to trauma centres have minor injuries. The transfer of patients with minor injuries to trauma centres is not associated with any known patient benefit and represents an opportunity to reduce healthcare costs and improve patient experience. In this study, we evaluated the relationship between hospital resources and overtriage, with the objective of identifying targets for system-level intervention.

METHODS

We conducted a population-based cohort study of adults, age ≥ 16, presenting with minor injuries to non-trauma centres in Ontario, Canada (2009-2020). The primary outcome was overtriage, defined as transfer to a trauma centre. Hierarchical logistic regression was used to evaluate the association between hospital resources and a patient's likelihood of being overtriaged, adjusting for case-mix.

RESULTS

amongst 165,302 patients with minor injuries, 15,641 (9.5 %) were transferred to a trauma centre (overtriage). Presence of a CT scanner, surgical support, or intensive care unit had no impact on a patient's likelihood of overtriage. Relative to community hospitals, presentation to a teaching hospital was independently associated with greater odds of overtriage (OR 2.97, 95 % CI: 1.26-7.00). Accounting for case-mix and resources, the median difference in a patient's odds of overtriage varied 3.7-fold across non-trauma centres (MOR 3.76).

CONCLUSIONS

There is significant variability in overtriage across non-trauma centres, even after adjusting for case-mix and hospital resources. These finding suggests that some centres have developed processes to minimize overtriage independent of available resources. Broad implementation of these processes may represent an opportunity for system-wide quality improvement.

A study protocol for a predictive model to assess population-based avoidable hospitalization risk: Avoidable Hospitalization Population Risk Prediction Tool (AvHPoRT)

INTRODUCTION

Avoidable hospitalizations are considered preventable given effective and timely primary care management and are an important indicator of health system performance. The ability to predict avoidable hospitalizations at the population level represents a significant advantage for health system decision-makers that could facilitate proactive intervention for ambulatory care-sensitive conditions (ACSCs). The aim of this study is to develop and validate the Avoidable Hospitalization Population Risk Tool (AvHPoRT) that will predict the 5-year risk of first avoidable hospitalization for seven ACSCs using self-reported, routinely collected population health survey data.

METHODS AND ANALYSIS

The derivation cohort will consist of respondents to the first 3 cycles (2000/01, 2003/04, 2005/06) of the Canadian Community Health Survey (CCHS) who are 18-74 years of age at survey administration and a hold-out data set will be used for external validation. Outcome information on avoidable hospitalizations for 5 years following the CCHS interview will be assessed through data linkage to the Discharge Abstract Database (1999/2000-2017/2018) for an estimated sample size of 394,600. Candidate predictor variables will include demographic characteristics, socioeconomic status, self-perceived health measures, health behaviors, chronic conditions, and area-based measures. Sex-specific algorithms will be developed using Weibull accelerated failure time survival models. The model will be validated both using split set cross-validation and external temporal validation split using cycles 2000-2006 compared to 2007-2012. We will assess measures of overall predictive performance (Nagelkerke R2), calibration (calibration plots), and discrimination (Harrell's concordance statistic). Development of the model will be informed by the Transparent Reporting of a multivariable prediction model for Individual Prognosis or Diagnosis (TRIPOD) statement.

ETHICS AND DISSEMINATION

This study was approved by the University of Toronto Research Ethics Board. The predictive algorithm and findings from this work will be disseminated at scientific meetings and in peer-reviewed publications.

Acute health care use among children during the first 2.5 years of the COVID-19 pandemic in Ontario, Canada: a population-based repeated cross-sectional study

BACKGROUND

The effects of the decline in health care use at the start of the COVID-19 pandemic on the health of children are unclear. We sought to estimate changes in rates of severe and potentially preventable health outcomes among children during the pandemic.

METHODS

We conducted a repeated cross-sectional study of children aged 0-17 years using linked population health administrative and disease registry data from January 2017 through August 2022 in Ontario, Canada. We compared observed rates of emergency department visits and hospital admissions during the pandemic to predicted rates based on the 3 years preceding the pandemic. We evaluated outcomes among children and neonates overall, among children with chronic health conditions and among children with specific diseases sensitive to delays in care.

RESULTS

All acute care use for children decreased immediately at the onset of the pandemic, reaching its lowest rate in April 2020 for emergency department visits (adjusted relative rate [RR] 0.28, 95% confidence interval [CI] 0.28-0.29) and hospital admissions (adjusted RR 0.43, 95% CI 0.42-0.44). These decreases were sustained until September 2021 and May 2022, respectively. During the pandemic overall, rates of all-cause mortality, admissions for ambulatory care-sensitive conditions, newborn readmissions or emergency department visits or hospital admissions among children with chronic health conditions did not exceed predicted rates. However, after declining significantly between March and May 2020, new presentations of diabetes mellitus increased significantly during most of 2021 (peak adjusted RR 1.49, 95% CI 1.28-1.74 in July 2021) and much of 2022. Among these children, presentations for diabetic ketoacidosis were significantly higher than expected during the pandemic overall (adjusted RR 1.14, 95% CI 1.00-1.30). We observed similar time trends for new presentations of cancer, but we observed no excess presentations of severe cancer overall (adjusted RR 0.91, 95% CI 0.62-1.34).

INTERPRETATION

In the first 30 months of the pandemic, disruptions to care were associated with important delays in new diagnoses of diabetes but not with other acute presentations of select preventable conditions or with mortality. Mitigation strategies in future pandemics or other health system disruptions should include education campaigns around important symptoms in children that require medical attention.

Prevalence of Hepatitis B in Canadian First-Time Blood Donors: Association with Social Determinants of Health

Hepatitis B is transmitted sexually, by blood contact, and vertically from mother to child. Chronic hepatitis B is often seen in immigrants from higher-prevalence countries and their Canadian-born children. We assessed the relationship between hepatitis B and social determinants of health. Included were 1,539,869 first-time Canadian blood donors from April 2005 to December 2022. All donations were tested for hepatitis B markers. Logistic regression was fit with chronic hepatitis B as the dependent variable and age, sex, year, and ethnocultural composition and material deprivation quintiles as independent variables. Chronic hepatitis B prevalence was 47.5/100,000 (95% CI 41.5-53.5, years 2017-2022). Chronic hepatitis B prevalence was elevated in males, older age groups, and those living in more materially deprived and higher ethnocultural neighbourhoods. Of 212,518 donors from 2020 to 2022 with race/ethnicity data, chronic hepatitis B prevalence was highest in East Asians. The findings are consistent with infections in immigrants, acquired in their country of origin, in their Canadian-born children and in those with other risks. As blood donors are a low-risk population unaware of their infection and unlikely to seek testing, our results highlight the ongoing public health challenges of diagnosing chronic hepatitis B and treating it when appropriate.

Stroke risk in women with atrial fibrillation

BACKGROUND AND AIMS

Female sex is associated with higher rates of stroke in atrial fibrillation (AF) after adjustment for other CHA2DS2-VASc factors. This study aimed to describe sex differences in age and cardiovascular care to examine their relationship with stroke hazard in AF.

METHODS

Population-based cohort study using administrative datasets of people aged ≥66 years diagnosed with AF in Ontario between 2007 and 2019. Cause-specific hazard regression was used to estimate the adjusted hazard ratio (HR) for stroke associated with female sex over a 2-year follow-up. Model 1 included CHA2DS2-VASc factors, with age modelled as 66-74 vs. ≥ 75 years. Model 2 treated age as a continuous variable and included an age-sex interaction term. Model 3 further accounted for multimorbidity and markers of cardiovascular care.

RESULTS

The cohort consisted of 354 254 individuals with AF (median age 78 years, 49.2% female). Females were more likely to be diagnosed in emergency departments and less likely to receive cardiologist assessments, statins, or LDL-C testing, with higher LDL-C levels among females than males. In Model 1, the adjusted HR for stroke associated with female sex was 1.27 (95% confidence interval 1.21-1.32). Model 2 revealed a significant age-sex interaction, such that female sex was only associated with increased stroke hazard at age >70 years. Adjusting for markers of cardiovascular care and multimorbidity further decreased the HR, so that female sex was not associated with increased stroke hazard at age ≤80 years.

CONCLUSION

Older age and inequities in cardiovascular care may partly explain higher stroke rates in females with AF.

Socioeconomic representativeness of Australian, Canadian and British cohorts from the paediatric diabetes AdDIT study: comparisons to regional and national data

BACKGROUND

Given limited data regarding the involvement of disadvantaged groups in paediatric diabetes clinical trials, this study aimed to evaluate the socioeconomic representativeness of participants recruited into a multinational clinical trial in relation to regional and national type 1 diabetes reference populations.

METHODS

Retrospective, cross-sectional evaluation of a subset of adolescent type 1 diabetes cardiorenal intervention trial (AdDIT) participants from Australia (n = 144), Canada (n = 312) and the UK (n = 173). Validated national measures of deprivation were used: the Index of Relative Socioeconomic Disadvantage (IRSD) 2016 (Australia), the Material Resources (MR) dimension of the Canadian Marginalisation index 2016 (Canada) and the Index of Multiple Deprivation (IMD) 2015 (UK). Representativeness was assessed by comparing the AdDIT cohort's distribution of deprivation quintiles with that of the local paediatric type 1 diabetes population (regional), and the broader type 1 diabetes population for which the trial's intervention was targeted (national).

RESULTS

Recruited study cohorts from each country had higher proportions of participants with higher SES, and significant underrepresentation of lower SES, in relation to their national references. The socioeconomic make-up in Australia mirrored that of the regional population (p = 0.99). For Canada, the 2nd least deprived (p = 0.001) and the most deprived quintiles (p < 0.001) were over- and under-represented relative to the regional reference, while the UK featured higher regional and national SES bias with over-representation and under-representation from the least-deprived and most-deprived quintiles (p < 0.0001).

CONCLUSIONS

Significant national differences in trial participation of low SES participants were observed, highlighting limitations in access to clinical research and the importance of reporting sociodemographic representation in diabetes clinical trials.

TRIAL REGISTRATION

NCT01581476. Registered on 20 April 2012.

Association of maternal risk factors with infant maltreatment: an administrative data cohort study

OBJECTIVE

We aimed to evaluate the risk of infant maltreatment associated with commonly used criteria for home visiting programmes: young maternal age, maternal adversity (homelessness, substance abuse, intimate partner violence), newcomer status and mental health concerns in Ontario, Canada.

DESIGN

This retrospective cohort study included infants born in hospital in Ontario from 1 April 2005 to 31 March 2017 captured in linked health administrative and demographic databases. Infants were followed from newborn hospitalisation until 1 year of age for child maltreatment captured in healthcare or death records. The association between type and number of maternal risk factors, and maltreatment, was analysed using multivariable logistic regression modelling, controlling for infant characteristics and material deprivation. Further modelling explored the association of each year of maternal age with maltreatment.

RESULTS

Of 989 586 infants, 434 (0.04%) had recorded maltreatment. Maternal age <22 years conferred higher risk of infant maltreatment (adjusted OR (aOR) 5.5, 95% CI 4.5 to 6.8) compared with age ≥22 years. Maternal mental health diagnoses (aOR 2.0, 95% CI 1.6 to 2.5) were also associated with maltreatment, while refugee status appeared protective (aOR 0.6, 95% CI 0.4 to 1.0). The odds of maltreatment increased with higher numbers of maternal risk factors. Maternal age was associated with maltreatment until age 28 years.

CONCLUSION

Infants born to young mothers are at greater risk of infant maltreatment, and this association remained until age 28 years. These findings are important for ensuring public health interventions are supporting populations experiencing structural vulnerabilities with the aim of preventing maltreatment.

Association of neighbourhood-level material deprivation with adverse outcomes and processes of care among patients with heart failure in a single-payer healthcare system: A population-based cohort study

AIM

We studied the association between neighbourhood material deprivation, a metric estimating inability to attain basic material needs, with outcomes and processes of care among incident heart failure patients in a universal healthcare system.

METHODS AND RESULTS

In a population-based retrospective study (2007-2019), we examined the association of material deprivation with 1-year all-cause mortality, cause-specific hospitalization, and 90-day processes of care. Using cause-specific hazards regression, we quantified the relative rate of events after multiple covariate adjustment, stratifying by age ≤65 or ≥66 years. Among 395 763 patients (median age 76 [interquartile range 66-84] years, 47% women), there was significant interaction between age and deprivation quintile for mortality/hospitalization outcomes (p ≤ 0.001). Younger residents (age ≤65 years) of the most versus least deprived neighbourhoods had higher hazards of all-cause death (hazard ratio [HR] 1.19, 95% confidence interval [CI] 1.10-1.29]) and cardiovascular hospitalization (HR 1.29 [95% CI 1.19-1.39]). Older individuals (≥66 years) in the most deprived neighbourhoods had significantly higher hazard of death (HR 1.11 [95% CI 1.08-1.14]) and cardiovascular hospitalization (HR 1.13 [95% CI 1.09-1.18]) compared to the least deprived. The magnitude of the association between deprivation and outcomes was amplified in the younger compared to the older age group. More deprived individuals in both age groups had a lower hazard of cardiology visits and advanced cardiac imaging (all p < 0.001), while the most deprived of younger ages were less likely to undergo implantable cardioverter-defibrillator/cardiac resynchronization therapy-pacemaker implantation (p = 0.023), compared to the least deprived.

CONCLUSION

Patients with newly-diagnosed heart failure residing in the most deprived neighbourhoods had worse outcomes and reduced access to care than those less deprived.