Researchers at Kaiser Permanente have found that colorectal cancer disparities between Black and white adults were eliminated in Northern California after the healthcare organization instituted a regionwide, structured colorectal cancer screening program.
“Our study found that organized screening works to improve colorectal cancer outcomes for all of our members,” said the study’s senior author Theodore Levin, M.D., a research scientist at the Kaiser Permanente Division of Research and a gastroenterologist with The Permanente Medical Group, in a statement. “I knew our program had helped to reduce disparities, but I was surprised by the magnitude and the rate of improvement. It exceeded my expectations.”
Disparities between Black and white adults in colorectal cancer screening, incidence, and death rates have been documented for more than 40 years. Screening programs create an opportunity to find colorectal cancers when they are small and easier to treat. Screening can also prevent cancers from developing through the removal of precancerous polyps.
The new study, published February 24 in the New England Journal of Medicine, looked at colorectal cancer screening participation, incidence, and death rates for Black and white Kaiser Permanente members in Northern California age 50 to 75 from 2000 through 2019. The 19-year time period spanned 6 years before and 11 years after the colorectal cancer screening program was rolled out in 2006 through 2008.
In 2009, the colorectal cancer death rate (per 100,000) was 54.2 for Black members and 32.6 for white members. By 2019, death rates had fallen by more than half among Black members — decreasing to 20.9 — compared to 19.3 for white members, essentially eliminating the previous disparity. Colorectal cancer incidence also markedly decreased with similar rates seen between Black and white members.
The findings highlight the need for healthcare organizations to address the social and structural barriers that contribute to ongoing health disparities. “Many people have sought to show that health equity is not just a pipe dream,” said the study’s co-lead author Chyke Doubeni, M.B.B.S., M.P.H., who directs the Mayo Clinic Center for Health Equity and Community Engagement Research, in a statement. “This study shows how a thoughtful, intentional, coordinated, and sustained approach to delivering care in an equitable manner can eliminate health disparities.”
The colorectal cancer screening program identifies who needs screening and offers a choice of screening tests. Program managers and electronic systems identify all eligible members who are not up to date and automated alerts remind health care providers to offer screening at clinic visits. For members who are not up to date with screening, a fecal immunochemical test (FIT) is mailed annually. These tests are completed at home and returned by mail. Patients can request a colonoscopy, rather than use a FIT kit.
After starting organized screening outreach, the proportions of people up to date with screening rapidly increased, from about 40 percent among both Black and white Kaiser Permanente members in Northern California in 2009 to 80 percent among Black members and 83 percent among white members by 2019.
The research team is already discussing ways to perfect and expand the program. “We are always looking to improve, to understand why a small proportion of people choose not to be screened, to identify those at highest risk for more intensive screening, and to increase efforts for culturally appropriate care,” said Douglas Corley, M.D., Ph.D., M.P.H., the study’s co-lead author, and a research scientist at the Kaiser Permanente Division of Research and a gastroenterologist with The Permanente Medical Group. “Our findings suggest similar organized approaches can play a major role nationally and internationally in decreasing disparities for colorectal cancer and potentially for other diseases,” he added in a statement.
The study was funded by the National Cancer Institute.
