Mortality

“Ontario Population Trends in Improved Mortality: Informing Sustainability & Equity of the health care system”

Wide variations in health care utilization and mortality across the population are a signal that the health system is not functioning to its full potential for all members of society. Advancements in medical and public health interventions have led to large improvements in population health and mortality; however, not all groups have benefited equally. Despite a universal health system, there is ample evidence that individuals of higher socio-economic status (SES) have experienced greater reductions in mortality than the less well off. These disparities have implications for overall population health and health system sustainability and equity.

Project Overview

The Ontario Population Trends in Improved Mortality: Informing Sustainability & Equity of the health care system (OPTIMISE) research program represented a cross-sectoral, multidisciplinary effort to generate actionable solutions to improve both population health and health care sustainability while reducing growing mortality gaps among Ontario’s marginalized populations. The  project used novel and comprehensive multi-linked mortality files to develop measures of health system functioning and inform health system planning in Ontario. The OPTIMISE Research Program embraced an integrated knowledge translation approach,  in which we assembled a steering committee of senior health system decision  makers from the major health agencies of Ontario. The results of the analyses were used to facilitate discussions with health system leaders about strategic priorities to improve health outcomes and reduce disparities in mortality declines in Ontario.

The OPTIMISE research program examined three main areas:

1. We analyzed all-cause, premature, and cause-specific mortality trends overall in Ontario and across marginalized groups, SES groups, immigrants, chronic disease cohorts and life-stages to identify disparities in overall and preventable mortality.  

Key learnings:  We found that despite large improvements in population mortality, certain subpopulations within Ontario are not benefiting fully from public health and health care system improvements. The existence of steep socioeconomic gradients in mortality suggests that interventions must include a strong focus on health equity, which are signatures of a population health approach.

• Buajitti E, Frank J, Watson T, Kornas K, & Rosella LC. (2020). Changing relative and absolute socioeconomic health inequalities in Ontario, Canada: A population-based cohort study of adult premature mortality, 1992 to 2017. PLOS ONE, 15(4), e0230684. https://doi.org/10.1371/journal.pone.0230684 
• Buajitti E, & Rosella LC. (2023). Neighborhood socioeconomic improvement, residential mobility and premature death: A population-based cohort study and inverse probability of treatment weighting analysis. International Journal of Epidemiology, 52(2), 489–500. https://doi.org/10.1093/ije/dyac117 
• Buajitti E, Watson T, Norwood T, Kornas K, Bornbaum C, Henry D, & Rosella LC. (2019). Regional variation of premature mortality in Ontario, Canada: A spatial analysis. Population Health Metrics, 17(1), 9. https://doi.org/10.1186/s12963-019-0193-9 
• Henry D, Buajitti E, Rosella L. Regional Inequalities in All-Cause and Premature Mortality in Ontario. Healthc Pap. 2018 Jan;17(3):28-34. doi: 10.12927/hcpap.2018.25504. PMID: 30052183. https://doi.org/doi:10.12927/hcpap.2018.25504 
• Khan, AM, Urquia, M, Kornas, K, Henry, D, Cheng, SY, Bornbaum, C, & Rosella LC. (2017). Socioeconomic gradients in all-cause, premature and avoidable mortality among immigrants and long-term residents using linked death records in Ontario, Canada. J Epidemiol Community Health, 71(7), 625–632. https://doi.org/10.1136/jech-2016-208525 
• Lachaud J, Donnelly PD, Henry D, Kornas K, Calzavara A, Bornbaum C, & Rosella LC. (2017). A population-based study of homicide deaths in Ontario, Canada using linked death records. International Journal for Equity in Health, 16(1). https://doi.org/10.1186/s12939-017-0632-9 
• Lachaud J, Donnelly P, Henry D, Kornas K, Fitzpatrick T, Calzavara A, Bornbaum C, & Rosella LC. (2018). Characterising violent deaths of undetermined intent: A population-based study, 1999–2012. Injury Prevention, 24(6), 424–430. https://doi.org/10.1136/injuryprev-2017-042376 
• Liang CY, Buajitti E, Kornas K, Diemert LM, Bornbaum C, Henry D, & Rosella LC. (2020). Canadian atlas of premature mortality, 1992-2015: Cross-provincial comparisons. Population Health Analytics Lab.
• Rosella LC, & Buajitti E. (2024). Risk of premature mortality due to smoking, alcohol use, obesity and physical activity varies by income: A population-based cohort study. SSM – Population Health, 25, 101638. https://doi.org/10.1016/j.ssmph.2024.101638 
• Rosella LC, Calzavara A, Frank JW, Fitzpatrick T, Donnelly PD, & Henry D. (2016). Narrowing mortality gap between men and women over two decades: A registry-based study in Ontario, Canada. BMJ Open, 6(11), e012564. https://doi.org/10.1136/bmjopen-2016-012564 
• Rosella LC, Kornas K, Huang A, Grant L, Bornbaum C, & Henry D. (2019). Population risk and burden of health behavioral–related all-cause, premature, and amenable deaths in Ontario, Canada: Canadian Community Health Survey–linked mortality files. Annals of Epidemiology, 32, 49-57.e3. https://doi.org/10.1016/j.annepidem.2019.01.009 

2. We conducted multiple studies with unique data linkages to measure the individual health conditions and system level health care utilization and costs associated with mortality trends over time, sub-populations and age groups. 

Key learnings: Our findings emphasize the importance of prevention to reduce the prevalence of risk behaviours that contribute to a large burden of premature deaths that are amenable to the health system. The trend toward greater multimorbidity over time and hospital-centered care at the end of life underscores the importance of integrated health care approaches to prevent and manage multiple complex conditions.

• O’Neill M, Buajitti E, Donnelly PD, Kornas K, & Rosella LC. (2021). Characterizing mental health/addictions and assault visits in the year prior to death: A population-based linked cohort study of homicide victims. International Journal of Population Data Science, 6(1), Article 1. https://doi.org/10.23889/ijpds.v6i1.1410 
• O’Neill M, Buajitti E, Donnelly PD, Lewis J, Kornas K, & Rosella LC. (2020). Characterising risk of homicide in a population-based cohort. J Epidemiol Community Health, 74(12), 1028–1034. https://doi.org/10.1136/jech-2019-213249 
• Rosella LC, Kornas K, Negatu E, & Zhou L. (2023). Variations in all-cause mortality, premature mortality and cause-specific mortality among persons with diabetes in Ontario, Canada. BMJ Open Diabetes Research and Care, 11(3), e003378. https://doi.org/10.1136/bmjdrc-2023-003378 
• Rosella LC, Kornas K, Huang A, Bornbaum C, Henry D, & Wodchis WP. (2018). Accumulation Of Chronic Conditions At The Time Of Death Increased In Ontario From 1994 To 2013. Health Affairs, 37(3), 464–472. https://doi.org/10.1377/hlthaff.2017.1150 
• Rosella LC, Negatu E, Kornas K, Chu C, Zhou L, & Buajitti E. (2023). Multimorbidity at time of death among persons with type 2 diabetes: a population-based study in Ontario, Canada. BMC Endocrine Disorders, 23(1), 127. 
• Rosella LC, Kornas K, Bornbaum C, Huang A, Watson T, Shuldiner J, & Wodchis WP. (2020). Population-based estimates of health care utilization and expenditures by adults during the last 2 years of life in Canada’s single-payer health system. JAMA Network Open, 3(4), e201917-e201917.  

3. We conducted a systematic review of mortality based indicators for measuring health system performance and population health. 

Key learnings: The review confirmed the utility of premature mortality as an meaningful indicator of population health and overall health system performance.

• Liang CY, Kornas K, Bornbaum C, Shuldiner J, De Prophetis E, Buajitti E, & Rosella LC. (2023). Mortality-based indicators for measuring health system performance and population health in high-income countries: a systematic review. IJQHC Communications, 3(2), lyad010.