Breast cancer screening disparities among immigrant women by world region of origin: a population‐based study in Ontario, Canada

Abstract

Rates of mammography screening for breast cancer are disproportionately low in certain subgroups including low‐income and immigrant women. The purpose of the study was to examine differences in rates of appropriate breast cancer screening (i.e., screening mammography every 2 years) among Ontario immigrant women by world region of origin and explore the association between appropriate breast cancer screening among these women groups and individual and structural factors. A cohort of 183,332 screening‐eligible immigrant women living in Ontario between 2010 and 2012 was created from linked databases and classified into eight world regions of origin. Appropriate screening rates were calculated for each region by age group and selected sociodemographic, immigration, and healthcare‐related characteristics. The association between appropriate screening across the eight regions of origin and selected sociodemographic, immigration, and health‐related characteristics was explored using multivariate Poisson regression. Screening varied by region of origin, with South Asian women (48.5%) having the lowest and Caribbean and Latin American women (63.7%) the highest cancer screening rates. Factors significantly associated with lower screening across the world regions of origin included living in the lowest income neighborhoods, having a refugee status, being a new immigrant, not having a regular physical examination, not being enrolled in a primary care patient enrollment model, having a male physician, and having an internationally trained physician. Multiple interventions entailing cross‐sector collaboration, promotion of patient enrollment models, community engagement, comprehensive and intensive outreach to women, and knowledge translation and transfer to physicians should be considered to address screening disparities among immigrant population. Consideration should be given to design and delivery of culturally appropriate and easily accessible cancer screening programs targeted at high‐ risk immigrant subgroups, such as women of South Asian origin, refugees, and new immigrants.

Breast screening participation and retention among immigrants and nonimmigrants in British Columbia: A population‐based study

“…Our participation results are consistent with prior Canadian studies that have reported lower breast cancer screening rates among immigrant women and specific immigrant subpopulations 9, 10, 11, 24. Recent data from Ontario, Canada9 demonstrated that among immigrant women, South Asians had the lowest breast screening utilization rate with the age 60‐69 group demonstrating lower screening than those aged 50‐59 years.…”

“…Geopolitical changes that have taken place over the immigration dates covered by this data file necessitated combining some countries into single groups: countries of the former Union of Socialist Soviet Republics (USSR) were assembled into a “Former USSR State” group; countries of the former Yugoslavia were aggregated into “Former Yugoslavia”; women from the People's Republic of China, Macau, Hong Kong, and Taiwan were combined into a single group labeled “CMHT” in all tables and figures. We created world regions based primarily on groupings of countries used by the World Bank19 and consistent with other recent Canadian studies 9, 20. Immigrant women from countries with <100 total women were pooled into an “Other Immigrant” group within each world region.…”

“…Disappointing breast screening participation rates as well as a desire to assess potential health inequities in cancer screening have motivated several recent investigations into potential screening disparities among socio‐demographic groups in Canada 4, 5, 6, 7, 8, 9, 10, 11, 12. Studies that have specifically examined breast screening have found screening disparities among immigrant subpopulations, as well as associations between mammography rates and duration of residence in Canada, primary care physician characteristics, primary care contacts, and other health and socio‐demographic variables 8, 9, 10, 11, 12.…”

“…Studies that have specifically examined breast screening have found screening disparities among immigrant subpopulations, as well as associations between mammography rates and duration of residence in Canada, primary care physician characteristics, primary care contacts, and other health and socio‐demographic variables 8, 9, 10, 11, 12. Research in Ontario, Canada identified disparities in screening rates among immigrant groups defined by world region of birth, including that South Asians had the lowest breast screening rates among all groups examined 9. Further research from the same population suggests that South Asian women may have more advanced breast tumors at the time of diagnosis 13, 14.…”

“…The world region categorization used in prior Canadian studies8, 9, 11 pooled women from a diverse set of countries, all of which have sizeable populations in Canada. For example, the East Asia/Pacific group included Filipino, Chinese, Korean, and Japanese immigrants.…”