Geographic inequalities in paediatric emergency department visits in Ontario and Alberta: a multilevel analysis of 2.5 million visits

According to recent data from the Canadian Institute for Health Information’s (CIHI) National Ambulatory Care Reporting System (NACRS), 21% of ED visits in 2019–2020 occurred among those aged 0 to 19 years in Canada, with 38% of these visits among children 0 to 4 years old [1]. The number of paediatric emergency department (PED) visits in Canada has been increasing [2‐4], contributing to healthcare concerns related to ED overcrowding and disruptions to patient flow and care [4]. For instance, in a retrospective cohort study of visits to eight PEDs in four provinces (British Columbia, Alberta, Manitoba, and Ontario), the volume of PED visits increased annually between 2010 and 2014 [3]. For instance, in one PED in British Columbia, the volume of visits increased 30% from 2002 to 2011 [4].

With approximately 70% of Canadians currently living in census metropolitan areas (CMAs) [5], it is important to understand the determinants of variations in PED visits within (intra-CMA variation) and across (inter-CMA variation) these metropolitan areas [6‐8]. These intra- and inter-urban variations may arise from contextual factors such as differential distribution of primary healthcare physicians within and across urban centers [9, 10], or proximity to healthcare facilities [11, 12]. Previous research has indicated that greater supply of primary care providers is associated with fewer non-urgent ED visits among children [13], and proximity to healthcare facilities has also been found to play an important role in the use of EDs [14]. Additionally, some research has highlighted the impact of area-level deprivation on health services utilization as children who live in deprived areas tend to have worse health outcomes than children living in more advantaged areas [6, 15]. With increasing PED visits in Canada, additional research on intra- and inter-regional variations in ED visits among children can provide a better understanding of the patterns of PED utilization and further insight into how contextual features of the urban environment may be associated with these health events.

Currently, there is limited knowledge about geographic inequalities in PED visits in Canada’s urban areas and the contribution of contextual factors to these inequalities, with most studies focusing on intra-urban variation in PED visits for respiratory conditions [6‐8]. Therefore, this study aimed to quantify the magnitude of intra-metropolitan and inter-metropolitan variation in PED visits in large urban centers in Ontario and Alberta, Canada and assess if contextual factors related to material and social deprivation, proximity to healthcare facilities, and supply of family physicians can account for this variation.

The objective of this study was to assess the intra- and inter-metropolitan variation in PED visits in CMAs in Ontario and Alberta, Canada and to assess if contextual predictors related to material and social deprivation, proximity to healthcare facilities, and supply of family physicians can account for this variation. In total, there were 2,537,442 PED visits across 520 FSAs in CMAs in Alberta and Ontario. The overall crude FSA-level rate of PED visits was 415.38 per 1,000 children population. We found evidence of statistically significant and substantial intra- and inter-urban variation in the rates of PED visits. The interquartile range in FSA-level rates was 156,48 per 1,000 children population and, at the CMA level, the crude rate of PED visits was highest in Thunder Bay (771.65 per 1,000 children population) and lowest in Windsor (237.19 per 1,000 children population). In terms of the intra- and inter-metropolitan variation in PED visits, the FSA- and CMA-level variances were statistically significant across all models (before and after adjusting for age and sex and considering the contextual predictors). About 50% of the overall variance was due to differences between CMAs. The contextual predictors accounted for 31.41% and 18.61% of the CMA- and FSA-level variance, respectively; however, most of the original observed variation was not accounted for. Together, this indicates that there are significant inequalities in FSA-level rates of PED visits across CMAs and across FSAs that cannot be fully explained by age and sex distributions, nor by differences in material and social deprivation, proximity to healthcare facilities, or supply of family physicians. Furthermore, in the adjusted model including the contextual predictors, Thunder Bay, St. Catharines – Niagara, Belleville, and Brantford had significantly higher rates of PED visits than the overall mean rate of ED visits (651.88, 575.59, 563.93, and 553.65 per 1,000 children population, respectively), whereas Windsor, Ottawa, and Kitchener – Cambridge – Waterloo, had significantly lower rates of PED visits (259.09, 341.58, and 358.68 per 1,000 children population, respectively). The three CMAs in Alberta (Calgary, Edmonton, and Lethbridge) were not significantly different from the overall mean rate reported in the adjusted model with contextual predictors.

Our findings indicate that across the 19 CMAs included in this study, Thunder Bay – a CMA in northern Ontario – had the highest average rate of PED visits across all models. This finding aligns with previous research which indicates that residents of northern Ontario have poorer geographic access to primary healthcare, hospitals, and worse health status and outcomes [12, 26]. This is not just limited to adults, as children and youth living in northern Ontario had higher rates of hospitalization and mortality than the provincial rate [27]. Windsor, on the other hand, had the lowest average rate of PED visits across all models. Further research on potential confounding factors is needed to better understand why some children in some CMAs visit EDs more than children in other CMAs.

Geographic inequalities and intra-urban variation have been identified in previous studies in the provinces of Alberta and Ontario. In Calgary and Edmonton, Alberta, Serrano-Lomelin et al. found geographic inequalities and intra-urban variations in use of acute respiratory health services (hospitalizations and ED visits) during early childhood that could not be completely explained by area-level material and social deprivation, suggesting that other unmeasured contextual factors also played a role in influencing the use of these services [7]. They also found that small conglomerate areas across the city of Calgary had greater demand for acute paediatric respiratory health services, whereas in Edmonton, the demand for these services followed a regional-cluster spatial distribution [7]. Sheriff et al. found that the highest number of hot spots for paediatric asthma-related ED visit and re-visit rates in Ottawa, Ontario were within areas that were associated with neighborhood residential instability, material deprivation, dependency, and ethnic concentration [6].

This study addresses inequalities in overall ED utilization among children living in CMAs in Ontario and Alberta. We found that more socially, but not materially, deprived FSAs had increased rates of PED visits. Material and social deprivation have previously been found to be associated with increases in overall [28] and low-acuity [29] ED visits among the general population and with recurrent ED visits among the paediatric population [30]. Belon et al. found that social and material deprivation were significantly associated with episodes of care for paediatric respiratory diseases in Alberta; however, contrary to our study, there was a more consistent gradient of increased rates of ED visits for all respiratory diseases with material deprivation [15]. Children are often accompanied by parents or caregivers to the ED, and parents’ decision to seek care in EDs are complex and often extend beyond measures of socioeconomic status. Driving factors for parents bringing their child to the ED include feelings of anxiety, urgency, need for immediate care and reassurance, perceptions that the ED was the best place to receive care, and the convenience and access of EDs (i.e., not needing appointment and around-the-clock care). These feelings and perceptions may be exacerbated in single-parent families or among those who experience greater social deprivation, resulting in higher rates of ED visits [31, 32].

Closer proximity to healthcare facilities was associated with reduced rates of PED visits in our study, which is consistent with previous research. Results from a study in the United States found that children living closer to their primary care physician had lower ED use, while those living closer to an ED had higher ED use [14]. Although we did not assess proximity to hospitals separately, research has indicated that proximity to an ED results in higher use. In British Columbia, geographic proximity was one of the top reasons for parents’ bringing their child to the ED for non-emergent complaints [33]. Similarly, Shechter et al. found that living closer to the ED compared to the clinic was a significant predictor of ED utilization among children in the United States [34]. Thus, separate measures of proximity to specific healthcare facilities (e.g., hospitals, primary healthcare clinics) should be considered in future studies assessing geographic inequalities in PED visits.

Interestingly, we found that CMAs with a greater supply of family physicians also had higher rates of ED visits. While having greater numbers of family physicians would seemingly reduce rates of ED utilization, our results may stem from the unequal distribution of family physicians in an area, as opposed to absolute supply [9, 13]. Furthermore, the accessibility of family physicians and primary healthcare services (e.g., hours, location) may also contribute to ED visits. Children in the United Kingdom registered in practices that were easily accessible were 9% less likely to visit the ED [35]. Given that the contextual factors related to social and material deprivation, proximity to healthcare facilities, and supply of family physicians did not account for all the variation in PED visits, it is likely that other social and environmental factors at the neighbourhood-level, (e.g., safety, air pollution, and features of the built environment), may also affect the utilization of the ED by children.

In conclusion, there are geographic inequalities in the rates of PED visits across FSAs in Canada’s large urban centers. As some urban areas have higher rates of PED visits, there is a need to further explore the role of contextual factors, as they are important in addressing health inequalities, particularly in urban settings. It would also be beneficial to extend the scope of the current study to assess spatial distribution of inequalities in PED visits.