Assessing colorectal cancer screening and outcomes among First Nations people in Alberta

First Nations (FN) people in Canada are commonly diagnosed with colorectal cancers. Although Canada has treaty responsibilities to ensure FNs people have equitable access to quality health services, access to colorectal cancer screening in Canada by FNs people has not been fully assessed.

The objectives of our retrospective population-level study that linked multiple administrative databases were to investigate differences in colorectal cancer screening rates: participation, retention, positivity, follow-up colonoscopy, and invasive colorectal cancer detection, as well as wait times to follow-up colonoscopy, and stages at diagnosis between FNs and non-FNs people in Alberta. All Alberta residents eligible for colorectal cancer screening (aged 50-74) between 2012 and 2018 were included. The study and descriptive methods adhered to FNs principles of ownership, control, access, and possession.

FNs people were less likely to participate in colorectal cancer screening (lower by 15.9% among women, P < 0.00001, and 17.0% among men; P = 0.0007), and less likely to be retained in the screening program (lower by 11.6%, P = 0.0013, among women and 9.9% %, P = 0.034, among men). They were more likely to screen positive (average difference of 7.0% among women and 7.3%, among men, both P < 0.0002). Invasive colorectal cancer detection rates were higher (3.2/1000) versus (2.3/1000) as were late-stage diagnoses (61% versus 43%, P = P = 0.004) among FNs people than non-FNs people, respectively.

Higher invasive colorectal cancer detection rates and more late-stage diagnoses in FNs people can be due to lower participation and retention in colorectal cancer screening programs. Understanding and addressing the reasons for these inequities are needed to improve these outcomes for FNs people.