Grade 7 school performance of children born preterm: a retrospective Canadian Cohort study.

IMPORTANCE: Data on the middle school outcomes of preterm children are limited and have methodologic issues. OBJECTIVE: To study the association between preterm birth and grade 7 school performance. METHODS: A retrospective population-based cohort study of children born in Manitoba, Canada between 1994 and 2006 using their grade 7 school performance data. A secondary sibling cohort was created comprising children born preterm and their full-term siblings. Primary exposure was preterm birth categorized as <28, 28-33 and 34-36 weeks gestation. The two co-primary grade 7 outcome measures were: not meeting the mathematics competencies, and not meeting the student engagement competencies. Multivariable logistic regression models tested the association between preterm birth and both co-primary outcomes; adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were calculated. RESULTS: 7653 preterm (gestational age median [IQR]: 35 weeks [34,36]) and 110,313 term (40 [39,40]) were included. 43% of < 28 weeks, 18% of 28-33 weeks and 17% of 34-36 weeks had the mathematics co-primary outcome compared to 13% of term children. The corresponding % for the student engagement outcome were 42%, 24%, 24% and 24% respectively. Preterm birth was associated with the mathematics (<28 weeks: 5.48, 3.89-7.70; 28-33 weeks: 1.47, 1.27-1.70; 34-36 weeks: 1.26, 1.16-1.35) and student engagement outcomes (<28 weeks: 2.49, 1.76-3.51; 28-33 weeks: 1.21, 1.06-1.39; 34-36 weeks: 1.09, 1.01-1.16). However, there was no difference in outcomes among the sibling cohort. CONCLUSIONS AND RELEVANCE: Children born preterm had lower grade 7 performance compared to children born term in this population-based cohort. Screening and supports for them in their middle school years are warranted.

Risk Prediction Scores for Type 2 Diabetes Microvascular and Cardiovascular Complications Derived and Validated With Real-world Data From 2 Provinces: The DIabeteS COmplications (DISCO) Risk Scores.

OBJECTIVES: Existing tools to predict the risk of complications among people with type 2 diabetes poorly discriminate high- from low-risk patients. Our aim in this study was to develop risk prediction scores for major type 2 diabetes complications using real-world clinical care data, and to externally validate these risk scores in a different jurisdiction. METHODS: Using health-care administrative data and electronic medical records data, risk scores were derived using data from 25,088 people with type 2 diabetes from the Canadian province of Ontario, followed between 2002 and 2017. Scores were developed for major clinically important microvascular events (treatment for retinopathy, foot ulcer, incident end-stage renal disease), cardiovascular disease events (acute myocardial infarction, heart failure, stroke, amputation), and mortality (cardiovascular, noncardiovascular, all-cause). They were then externally validated using the independent data of 11,416 people with type 2 diabetes from the province of Manitoba. RESULTS: The 10 derived risk scores had moderate to excellent discrimination in the independent validation cohort, ranging from 0.705 to 0.977. Their calibration to predict 5-year risk was excellent across most levels of predicted risk, albeit with some displaying underestimation at the highest levels of predicted risk. CONCLUSIONS: The DIabeteS COmplications (DISCO) risk scores for major type 2 diabetes complications were derived and externally validated using contemporary real-world clinical data. As a result, they may be more accurate than other risk prediction scores derived using randomized trial data. The use of more accurate risk scores in clinical practice will help improve personalization of clinical care for patients with type 2 diabetes.

Comparison of socio-economic determinants of COVID-19 testing and positivity in Canada: A multi-provincial analysis.

BACKGROUND: The effects of the COVID-19 pandemic have been more pronounced for socially disadvantaged populations. We sought to determine how access to SARS-CoV-2 testing and the likelihood of testing positive for COVID-19 were associated with demographic factors, socioeconomic status (SES) and social determinants of health (SDH) in three Canadian provinces. METHODS: An observational population-based cross-sectional study was conducted for the provinces of Ontario, Manitoba and New Brunswick between March 1, 2020 and April 27, 2021, using provincial health administrative data. After excluding residents of long-term care homes, those without current provincial health insurance and those who were tested for COVID-19 out of province, records from provincial healthcare administrative databases were reviewed for 16,900,661 healthcare users. Data was modelled separately for each province in accordance to a prespecified protocol and follow-up consultations among provincial statisticians and collaborators. We employed univariate and multivariate regression models to examine determinants of testing and test results. RESULTS: After adjustment for other variables, female sex and urban residency were positively associated with testing, while female sex was negatively associated with test positivity. In New Brunswick and Ontario, individuals living in higher income areas were more likely to be tested, whereas in Manitoba higher income was negatively associated with both testing and positivity. High ethnocultural composition was associated with lower testing rates. Both high ethnocultural composition and high situational vulnerability increased the odds of testing positive for SARS-CoV-2. DISCUSSION: We observed that multiple demographic, income and SDH factors were associated with SARS-CoV-2 testing and test positivity. Barriers to healthcare access identified in this study specifically relate to COVID-19 testing but may reflect broader inequities for certain at-risk groups.

Changes in Prevalence and Incidence at the Population Level of Type 2 Diabetes in First Nations and All Other Adults in Manitoba.

OBJECTIVES: The prevalence of type 2 diabetes (T2D) is increasing and Indigenous populations are at highest risk. Canadian data are crucial for health planning. METHODS: Population-based, de-identified, linked databases were used to calculate the incidence and prevalence of T2D for registered adult First Nations Manitobans and all other adult Manitobans from 2011-2012 to 2016-2017. RESULTS: The crude prevalence of T2D increased over the 6-year study period. The crude incidence of T2D for First Nations Manitobans dropped from 11.02 to 9.74 per 1,000 person-years at risk and the crude incidence for all other Manitobans did not change; in the last 2-year period, it was 6.53 per 1,000 person-years at risk. When incidence was stratified by age, the results differed between the younger and older age groups. For First Nations individuals, the adjusted incidence of T2D for those <30 years old increased over time, with no change in those ≥30 years old. For all other Manitobans, crude incidence increased over time in the young and middle age ranges (i.e. 18 to 29 years and 35 to 44 years, respectively). Both age- and sex-adjusted relative prevalence (adjusted rate ratio [aRR], 3.47; 95% confidence interval [CI], 2.56 to 4.70) and incidence (aRR, 1.97; 95% CI, 1.51 to 2.56) were higher for First Nations Manitobans. CONCLUSIONS: The prevalence of T2D continues to increase and disproportionately affects First Nations populations. Furthermore, the incidence is increasing in the younger age groups. Prevention and screening programs must include younger age groups and partner with First Nations communities.

Grade 3 school performance among children born preterm: a population-based cohort study.

OBJECTIVE: To study the association between prematurity and grade 3 school performance in a contemporary cohort of children. METHODS: Population-based retrospective cohort study in Manitoba, Canada. Children born between 1999 and 2011 who had their grade 3 school performance data available were eligible. Preterm birth (<37 weeks) was the exposure of interest assessed using multivariable logistic regression models. Our primary outcomes were 'needs ongoing help' or 'outside the range' in at least two of each of the (1) four numeracy and (2) three reading competencies. RESULTS: Of the 186 956 eligible children, 101 436 children (7187 preterm (gestational age, median (IQR) 35 weeks (34, 36)) and 94 249 term (40 weeks (39,40)) were included. Overall, 19% of preterm and 14% of term children had the numeracy outcome (adjusted OR (aOR) 1.38; 95% CI 1.29 to 1.47, p<0.001), while 19% and 13% had the reading outcome (aOR 1.38; 1.29 to 1.48, p<0.001). These differences showed a gestational age gradient. Gestational age (for numeracy, <28 weeks aOR 4.93 (3.45 to 7.03), 28-33 weeks 1.72 (1.50 to 1.98), 34-36 weeks 1.24 (1.15 to 1.34); for reading, <28 weeks 3.51 (2.40 to 5.14), 28-33 weeks 1.72 (1.49 to 1.98), 34-36 weeks 1.24 (1.17-1.37)), male sex, small for gestational age and maternal medical and sociodemographic factors were associated with the numeracy and reading outcomes in this cohort. CONCLUSIONS AND RELEVANCE: Children born preterm had poorer performance in grade 3 numeracy and reading proficiencies than children born full term. All children born preterm, not just those born extremely preterm, should be screened for reading and numeracy performance in school and strategies implemented to address any deficits.

Maternal and neonatal outcomes in pregnancies with type 2 diabetes in First Nation and other Manitoban people: a population-based study.

BACKGROUND: First Nation people living in Canada experience a high prevalence of type 2 diabetes in pregnancy. In this study, we aimed to describe maternal and neonatal outcomes in First Nation and all other females with type 2 diabetes living in Manitoba, Canada. METHODS: This was a population-level retrospective cohort study using linked administrative data from Manitoba (2012-2017). We compared First Nation females with type 2 diabetes with all other Manitoban females with type 2 diabetes, using relative risks (RRs) and 95% confidence intervals (CIs). RESULTS: A total of 2181 females with type 2 diabetes were included, and 1218 (55.8%) were First Nation. First Nation females with type 2 diabetes were significantly more likely to experience stillbirth (RR 2.14, 95% CI 1.11-4.13) and perinatal death (RR 2.39, 95% CI 1.37-4.17) than all other Manitoban females with type 2 diabetes. Offspring of First Nation females with type 2 diabetes had a higher risk of most neonatal complications than offspring of all other Manitoban females with type 2 diabetes, including a higher risk of congenital malformations (RR 1.97, 95% CI 1.30-2.99), but First Nation people did not have a higher risk of most maternal complications. INTERPRETATION: First Nation pregnant individuals living with type 2 diabetes experienced a higher risk for adverse pregnancy outcomes than all other Manitoban females with type 2 diabetes. Additional studies are needed to identify both high-risk and protective factors for pregnancy complications in First Nation people living with type 2 diabetes in pregnancy.

Geographic concentration of SARS-CoV-2 cases by social determinants of health in metropolitan areas in Canada: a cross-sectional study.

BACKGROUND: Understanding inequalities in SARS-CoV-2 transmission associated with the social determinants of health could help the development of effective mitigation strategies that are responsive to local transmission dynamics. This study aims to quantify social determinants of geographic concentration of SARS-CoV-2 cases across 16 census metropolitan areas (hereafter, cities) in 4 Canadian provinces, British Columbia, Manitoba, Ontario and Quebec. METHODS: We used surveillance data on confirmed SARS-CoV-2 cases and census data for social determinants at the level of the dissemination area (DA). We calculated Gini coefficients to determine the overall geographic heterogeneity of confirmed cases of SARS-CoV-2 in each city, and calculated Gini covariance coefficients to determine each city's heterogeneity by each social determinant (income, education, housing density and proportions of visible minorities, recent immigrants and essential workers). We visualized heterogeneity using Lorenz (concentration) curves. RESULTS: We observed geographic concentration of SARS-CoV-2 cases in cities, as half of the cumulative cases were concentrated in DAs containing 21%-35% of their population, with the greatest geographic heterogeneity in Ontario cities (Gini coefficients 0.32-0.47), followed by British Columbia (0.23-0.36), Manitoba (0.32) and Quebec (0.28-0.37). Cases were disproportionately concentrated in areas with lower income and educational attainment, and in areas with a higher proportion of visible minorities, recent immigrants, high-density housing and essential workers. Although a consistent feature across cities was concentration by the proportion of visible minorities, the magnitude of concentration by social determinant varied across cities. INTERPRETATION: Geographic concentration of SARS-CoV-2 cases was observed in all of the included cities, but the pattern by social determinants varied. Geographically prioritized allocation of resources and services should be tailored to the local drivers of inequalities in transmission in response to the resurgence of SARS-CoV-2.

Dementia and depression with ischemic heart disease: a population-based longitudinal study comparing interventional approaches to medical management.

BACKGROUND: We compared the proportion of ischemic heart disease (IHD) patients newly diagnosed with dementia and depression across three treatment groups: percutaneous coronary intervention (PCI), coronary artery bypass grafting (CABG) and medical management alone (IHD-medical). METHODS AND FINDINGS: De-identified, individual-level administrative records of health service use for the population of Manitoba, Canada (approximately 1.1 million) were examined. From April 1, 1993 to March 31, 1998, patients were identified with a diagnosis of IHD (ICD-9-CM codes). Index events of CABG or PCI were identified from April 1, 1998 to March 31, 2003. Outcomes were depression or dementia after the index event. Patients were followed forward to March 31, 2006 or until censored. Proportional hazards regression analysis was undertaken. Independent variables examined were age, sex, diabetes, hypertension and income quintile, medical management alone for IHD, or intervention by PCI or CABG. Age, sex, diabetes, and presence of hypertension were all strongly associated with the diagnosis of depression and dementia. There was no association with income quintile. Dementia was less frequent with PCI compared to medical management; (HR = 0.65; p = 0.017). CABG did not provide the same protective effect compared to medical management (HR = 0.90; p = 0.372). New diagnosis depression was more frequent with interventional approaches: PCI (n = 626; hazard ratio = 1.25; p = 0.028) and CABG (n = 1124, HR = 1.32; p = 0.0001) than non-interventional patients (n = 34,508). Subsequent CABG was nearly 16-fold higher (p<0.0001) and subsequent PCI was 22-fold higher (p<0.0001) for PCI-managed than CABG-managed patients. CONCLUSIONS: Patients managed with PCI had the lowest likelihood of dementia-only 65% of the risk for medical management alone. Both interventional approaches were associated with a higher risk of new diagnosed depression compared to medical management. Long-term myocardial revascularization was superior with CABG. These findings suggest that PCI may confer a long-term protective effect from dementia. The mechanism(s) of dementia protection requires elucidation.

The Manitoba Healthy Baby Prenatal Benefit Program: who is participating?

BACKGROUND: Programs offering income supplements for lower-income pregnant women have been introduced in order to reduce the incidence of poor perinatal outcomes. This study used a population-based approach to examine the characteristics of mothers who received the Healthy Baby Prenatal Benefit in Manitoba. METHODS: All women giving birth between August 2001 and April 2003 (n = 22,643) were studied using de-identified linked administrative data. Multivariate logistic regression was used to determine factors that predicted receipt of the benefit, adjusting for potential confounding effects. Separate regressions were run for all mothers, and for a group of mothers eligible to receive the benefit (N = 1962). RESULTS: Almost 29% of mothers giving birth during the study period received the prenatal benefit. Mothers were more likely to receive the benefit if they: lived outside of Winnipeg; received income assistance during pregnancy; were younger at their first birth; were unmarried; made prenatal physician visits; experienced maternal depression; were having a first birth; and lived in the lowest income areas. Despite all being eligible, only 67% of non-Winnipeg and 80% of Winnipeg women receiving income assistance received the benefit. Factors related to benefit receipt for those eligible were: living in Winnipeg; making prenatal visits; not being a young teen at current birth; and experiencing a first birth. CONCLUSION: It is important to look not only at the characteristics of benefit recipients but also at those not receiving the benefit, in order to develop strategies to reach those who may most need and benefit from the program.

Does continuity of care with a family physician reduce hospitalizations among older adults?

OBJECTIVE: To examine the relation between continuity of primary care and hospitalizations. METHODS: Survey data from a representative sample of older adults aged 67 or over living in the province of Manitoba (n = 1863) were linked to administrative data, which provide complete records of physician visits and hospitalizations. A visit-based measure of continuity of care was derived using a majority-of-care definition, whereby individuals who made 75% of all their visits to family physicians (FPs) to the same FP were classified as having high continuity of care, and those with less than 75% of their visits to the same FP as having low continuity of care. Whether individuals were hospitalized (for either ambulatory care-sensitive conditions or all conditions) was also determined from administrative records. RESULTS: High continuity of care was associated with reduced odds of ambulatory care-sensitive hospitalizations (adjusted odds ratio = 0.67, confidence interval 0.51-0.90) controlling for demographic and self-reported, health-related measures. It was not related to hospitalizations for all conditions, however. CONCLUSIONS: The study highlights the importance of continuity of primary care in reducing potentially avoidable hospitalizations.

Does continuity of care matter in a universally insured population?

OBJECTIVE: To examine the relation between continuity of care and preventive health care and emergency department (ED) use in a universal health care system. DATA SOURCES/STUDY SETTING: Administrative data that capture health care use of the entire population of a midwestern Canadian city. STUDY DESIGN: A population-based, retrospective study of all individuals who had a least one physician contact in 1998 or 1999 (total N=536,893). METHODS: Logistic regressions were conducted to examine the relation between continuity of care, defined in terms of the proportion of total visits to family physicians (FPs) made to the same FP, and cervical cancer screening, breast cancer screening, influenza vaccination, pneumococcal vaccination, and ED visits, controlling for demographic variables, socioeconomic status (defined in terms of relative affluence of neighborhood of residence), and health status. PRINCIPAL FINDINGS: Continuity of care was related to better preventive health care and reduced ED use. A consistent socioeconomic gradient also emerged. For instance, the odds of having a mammogram was double for individuals living in the wealthiest neighborhoods, relative to those in the poorest neighborhoods (adjusted odds ratio=2.31, 99 percent CI 2.13-2.50). CONCLUSIONS: Having a long-term relationship with a single physician makes a difference even in a universal health care system. Moreover, socioeconomic disparities remain, suggesting the need to target specifically individuals from lower socioeconomic strata for preventive health care.