Mohammad R. Rezai

The Cardiovascular Health in Ambulatory Care Research Team (CANHEART) Using Big Data to Measure and Improve Cardiovascular Health and Healthcare Services

Background—The CArdiovascular HEalth in Ambulatory care Research Team (CANHEART) is conducting a unique, population-based observational research initiative aimed at measuring and improving cardiovascular health and the quality of ambulatory cardiovascular care provided in Ontario, Canada. A particular focus will be on identifying opportunities to improve the primary and secondary prevention of cardiovascular events in Ontario’s diverse multiethnic population. Methods and Results—A population-based cohort comprising 9.8 million Ontario adults ≥20 years in 2008 was assembled by linking multiple electronic survey, health administrative, clinical, laboratory, drug, and electronic medical record databases using encoded personal identifiers. The cohort includes ≈9.4 million primary prevention patients and ≈400 000 secondary prevention patients. Follow-up on clinical events is achieved through record linkage to comprehensive hospitalization, emergency department, and vital statistics administrative databases. Profiles of cardiovascular health and preventive care will be developed at the health region level, and the cohort will be used to study the causes of regional variation in the incidence of major cardiovascular events and other important research questions. Conclusions—Linkage of multiple databases will enable the CANHEART study cohort to serve as a powerful big data resource for scientific research aimed at improving cardiovascular health and health services delivery. Study findings will be shared with clinicians, policy makers, and the public to facilitate population health interventions and quality improvement initiatives.

The Incidence of Major Cardiovascular Events in Immigrants to Ontario, Canada: The CANHEART Immigrant Study.

Background —Immigrants from ethnic minority groups represent an increasing proportion of the population in many high-income countries but little is known about the causes and amount of variation between various immigrant groups in the incidence of major cardiovascular events. Methods and Results —We conducted the Cardiovascular Health in Ambulatory Care Research Team (CANHEART) Immigrant study, a big data initiative, linking information from Citizenship and Immigration Canadas Permanent Resident database to nine population-based health databases. A cohort of 824 662 first-generation immigrants aged 30 to 74 as of January 2002 from eight major ethnic groups and 201 countries of birth who immigrated to Ontario, Canada between 1985 and 2000 were compared to a reference group of 5.2 million long-term residents. The overall 10-year age-standardized incidence of major cardiovascular events was 30% lower among immigrants compared with long-term residents. East Asian immigrants (predominantly ethnic Chinese) had the lowest incidence overall (2.4 in males, 1.1 in females per 1000 person-years) but this increased with greater duration of stay in Canada. South Asian immigrants, including those born in Guyana had the highest event rates (8.9 in males, 3.6 in females per 1000 person-years), along with immigrants born in Iraq and Afghanistan. Adjustment for traditional risk factors reduced but did not eliminate differences in cardiovascular risk between various ethnic groups and long-term residents. Conclusions —Striking differences in the incidence of cardiovascular events exist among immigrants to Canada from different ethnic backgrounds. Traditional risk factors explain part but not all of these differences.Background— Immigrants from ethnic minority groups represent an increasing proportion of the population in many high-income countries, but little is known about the causes and amount of variation between various immigrant groups in the incidence of major cardiovascular events. Methods and Results— We conducted the Cardiovascular Health in Ambulatory Care Research Team (CANHEART) Immigrant Study, a big data initiative, linking information from Citizenship and Immigration Canada’s Permanent Resident database to 9 population-based health databases. A cohort of 824 662 first-generation immigrants aged 30 to 74 as of January 2002 from 8 major ethnic groups and 201 countries of birth who immigrated to Ontario, Canada between 1985 and 2000 were compared with a reference group of 5.2 million long-term residents. The overall 10-year age-standardized incidence of major cardiovascular events was 30% lower among immigrants than among long-term residents. East Asian immigrants (predominantly ethnic Chinese) had the lowest incidence overall (2.4 in males, 1.1 in females per 1000 person-years), but this increased with greater duration of stay in Canada. South Asian immigrants, including those born in Guyana, had the highest event rates (8.9 in males, 3.6 in females per 1000 person-years), along with immigrants born in Iraq and Afghanistan. Adjustment for traditional risk factors reduced but did not eliminate the differences in cardiovascular risk between various ethnic groups and long-term residents. Conclusions— Striking differences in the incidence of cardiovascular events exist among immigrants to Canada from different ethnic backgrounds. Traditional risk factors explain a part but not all of these differences.

The Risk of Ischemic Heart Disease and Stroke Among Immigrant Populations: A Systematic Review

BACKGROUND The increasing frequency of global migration to Canada and other high-income countries has highlighted the need for information on the risk of ischemic heart disease (IHD) and stroke among migrant populations. METHODS Using the MEDLINE and EMBASE databases, we conducted an English-language literature review of articles published from 2000 to 2014 to study patterns in the incidence of IHD or stroke in migrant populations to high-income countries. Our search revealed 17 articles of interest. All studies stratified immigrants according to country or region of birth, except 2 from Canada and 1 from Denmark, in which all immigrant groups were analyzed together. RESULTS The risk of IHD or stroke varied by country of origin, country of destination, and duration of residence. In our review we found that most migrant groups to Western Europe were at a similar or higher risk of IHD and stroke compared with the host population. Those at a higher risk included many Eastern European, Middle-Eastern, and South Asian immigrants. When duration of residence was considered, it appeared that in most migrants the risk of IHD worsened over time. In contrast, immigrants overall were at lower risk of myocardial infarction and stroke in Ontario compared with long-term residents of Canada. CONCLUSIONS The risks of IHD and stroke vary widely in immigrant populations in Western Europe. Detailed studies of immigrants to Canada according to country of birth and duration of residence should be undertaken to guide future cardiovascular health promotion initiatives.

Incidence of Major Cardiovascular Events in Immigrants to Ontario, CanadaCLINICAL PERSPECTIVE

Background —Immigrants from ethnic minority groups represent an increasing proportion of the population in many high-income countries but little is known about the causes and amount of variation between various immigrant groups in the incidence of major cardiovascular events. Methods and Results —We conducted the Cardiovascular Health in Ambulatory Care Research Team (CANHEART) Immigrant study, a big data initiative, linking information from Citizenship and Immigration Canadas Permanent Resident database to nine population-based health databases. A cohort of 824 662 first-generation immigrants aged 30 to 74 as of January 2002 from eight major ethnic groups and 201 countries of birth who immigrated to Ontario, Canada between 1985 and 2000 were compared to a reference group of 5.2 million long-term residents. The overall 10-year age-standardized incidence of major cardiovascular events was 30% lower among immigrants compared with long-term residents. East Asian immigrants (predominantly ethnic Chinese) had the lowest incidence overall (2.4 in males, 1.1 in females per 1000 person-years) but this increased with greater duration of stay in Canada. South Asian immigrants, including those born in Guyana had the highest event rates (8.9 in males, 3.6 in females per 1000 person-years), along with immigrants born in Iraq and Afghanistan. Adjustment for traditional risk factors reduced but did not eliminate differences in cardiovascular risk between various ethnic groups and long-term residents. Conclusions —Striking differences in the incidence of cardiovascular events exist among immigrants to Canada from different ethnic backgrounds. Traditional risk factors explain part but not all of these differences.Background— Immigrants from ethnic minority groups represent an increasing proportion of the population in many high-income countries, but little is known about the causes and amount of variation between various immigrant groups in the incidence of major cardiovascular events. Methods and Results— We conducted the Cardiovascular Health in Ambulatory Care Research Team (CANHEART) Immigrant Study, a big data initiative, linking information from Citizenship and Immigration Canada’s Permanent Resident database to 9 population-based health databases. A cohort of 824 662 first-generation immigrants aged 30 to 74 as of January 2002 from 8 major ethnic groups and 201 countries of birth who immigrated to Ontario, Canada between 1985 and 2000 were compared with a reference group of 5.2 million long-term residents. The overall 10-year age-standardized incidence of major cardiovascular events was 30% lower among immigrants than among long-term residents. East Asian immigrants (predominantly ethnic Chinese) had the lowest incidence overall (2.4 in males, 1.1 in females per 1000 person-years), but this increased with greater duration of stay in Canada. South Asian immigrants, including those born in Guyana, had the highest event rates (8.9 in males, 3.6 in females per 1000 person-years), along with immigrants born in Iraq and Afghanistan. Adjustment for traditional risk factors reduced but did not eliminate the differences in cardiovascular risk between various ethnic groups and long-term residents. Conclusions— Striking differences in the incidence of cardiovascular events exist among immigrants to Canada from different ethnic backgrounds. Traditional risk factors explain a part but not all of these differences.

Incidence of Major Cardiovascular Events in Immigrants to Ontario, CanadaCLINICAL PERSPECTIVE: The CANHEART Immigrant Study

Background —Immigrants from ethnic minority groups represent an increasing proportion of the population in many high-income countries but little is known about the causes and amount of variation between various immigrant groups in the incidence of major cardiovascular events. Methods and Results —We conducted the Cardiovascular Health in Ambulatory Care Research Team (CANHEART) Immigrant study, a big data initiative, linking information from Citizenship and Immigration Canadas Permanent Resident database to nine population-based health databases. A cohort of 824 662 first-generation immigrants aged 30 to 74 as of January 2002 from eight major ethnic groups and 201 countries of birth who immigrated to Ontario, Canada between 1985 and 2000 were compared to a reference group of 5.2 million long-term residents. The overall 10-year age-standardized incidence of major cardiovascular events was 30% lower among immigrants compared with long-term residents. East Asian immigrants (predominantly ethnic Chinese) had the lowest incidence overall (2.4 in males, 1.1 in females per 1000 person-years) but this increased with greater duration of stay in Canada. South Asian immigrants, including those born in Guyana had the highest event rates (8.9 in males, 3.6 in females per 1000 person-years), along with immigrants born in Iraq and Afghanistan. Adjustment for traditional risk factors reduced but did not eliminate differences in cardiovascular risk between various ethnic groups and long-term residents. Conclusions —Striking differences in the incidence of cardiovascular events exist among immigrants to Canada from different ethnic backgrounds. Traditional risk factors explain part but not all of these differences.Background— Immigrants from ethnic minority groups represent an increasing proportion of the population in many high-income countries, but little is known about the causes and amount of variation between various immigrant groups in the incidence of major cardiovascular events. Methods and Results— We conducted the Cardiovascular Health in Ambulatory Care Research Team (CANHEART) Immigrant Study, a big data initiative, linking information from Citizenship and Immigration Canada’s Permanent Resident database to 9 population-based health databases. A cohort of 824 662 first-generation immigrants aged 30 to 74 as of January 2002 from 8 major ethnic groups and 201 countries of birth who immigrated to Ontario, Canada between 1985 and 2000 were compared with a reference group of 5.2 million long-term residents. The overall 10-year age-standardized incidence of major cardiovascular events was 30% lower among immigrants than among long-term residents. East Asian immigrants (predominantly ethnic Chinese) had the lowest incidence overall (2.4 in males, 1.1 in females per 1000 person-years), but this increased with greater duration of stay in Canada. South Asian immigrants, including those born in Guyana, had the highest event rates (8.9 in males, 3.6 in females per 1000 person-years), along with immigrants born in Iraq and Afghanistan. Adjustment for traditional risk factors reduced but did not eliminate the differences in cardiovascular risk between various ethnic groups and long-term residents. Conclusions— Striking differences in the incidence of cardiovascular events exist among immigrants to Canada from different ethnic backgrounds. Traditional risk factors explain a part but not all of these differences.

DIFFUSION OF CARDIAC COMPUTED TOMOGRAPHY ANGIOGRAPHY AND ITS EFFECT ON CORONARY ANGIOGRAPHY IN ONTARIO, CANADA

Over the past several years, cardiac computed tomography angiography (CCTA) has emerged as a non-invasive method of assessing coronary artery disease. The province of Ontario began funding CCTA through its publicly funded Ontario Health Insurance Plan at the beginning of fiscal year 2011 (April 2011