Breast cancer screening study shows disparities among Ontario immigrant women

Regular breast cancer screening can save women's lives by detecting cancer at an early, treatable stage. Mandana Vahabi's research has shown that immigrant women in Ontario have lower breast cancer screening rates overall and that could explain the high rate of advanced breast cancer among immigrant women.

Vahabi's new population-based study, "Breast Cancer Screening Disparities Among Immigrant Women by World Region of Origin: A Population-Based Study in Ontario, Canada", published in Cancer Medicine this month, investigated and observed for the first time striking disparities in screening rates among 183,000 Ontario immigrant women (ages 50-69) from eight world regions of origin.

"Previous studies have looked at immigrants as a homogeneous population. We wanted to see if there were significant differences among immigrant populations by their region of origin and we found that screening is disproportionately low for certain subgroups of women," says Vahabi, a professor in Ryerson's Daphne Cockwell School of Nursing, Faculty of Community Services.

Her study showed that fewer than half (48.5 per cent) of eligible South Asian women between 50 and 69 had breast cancer screening every two years, far below the provincial rate of 61 per cent and the Cancer Care Ontario target rate of 70 per cent. Eastern European, Central Asian and Sub-Saharan African women also had lower rates of screening. Women from the Caribbean, Latin America and Western Europe had slightly higher screening rates than the provincial average.

"These findings help healthcare planners and policy makers to know which groups are more at risk of being under-screened. By identifying these differences, we can develop culturally informed strategies and outreach programs to help more women from these groups get screened," explains Vahabi, who led the study in collaboration with Dr. Aisha Lofters and Dr. Richard Glazier of St. Michael's Hospital and the Institute for Clinical Evaluative Sciences (ICES), and Matthew Kumar, also with ICES.

Vahabi also found other key factors that made urban immigrant women less likely to be screened than Canadian-born women, both in this study and a 2015 BMC Public Health study titled "Breast Cancer Screening Disparities in Ontario, Canada" that analyzed data for 1.4 million women in Ontario who were eligible for screening from 2010 to 2012.

New and recent immigrants, and refugees, had lower screening rates. Barriers to screening included not having a regular physical check-up, not being enrolled in a primary care patient enrolment model, having a male physician, having an internationally trained physician and living in a low-income neighbourhood.

She recommends proactive strategies to give immigrant women greater access to primary care patient enrolment models (such as Family Health Networks) and female health professionals, including nurse practitioners.

Settlement and community agencies should help educate new and recent immigrants, and refugees, about the benefits of preventive breast and cervical cancer screening and the services to which they are entitled. "We also need targeted, culturally tailored programs that identify and address barriers for high-risk subgroups, such as South Asian and Sub-Saharan women," she says, noting that cervical cancer screening rates are lower for these women too.

Vahabi believes a multi-pronged approach that promotes preventive screening for breast, cervical and colorectal cancer can have a greater impact than focusing on one cancer alone. "If we can increase preventive cancer screening among all groups of immigrant women to the level of the general population, we'll detect cancer earlier, save many lives and reduce the economic burden on society," she says.