U.S. colon cancer screening rates vary widely

Last Updated: 2018-03-28

By Lisa Rapaport

(Reuters Health) - The proportion of U.S. adults who get recommended colon cancer screenings has never been as high as doctors would like, but a new study suggests that it's much lower than expected in some pockets of the country.

Adults aged 50 to 75 are typically advised to get screened every 10 years with a colonoscopy or annually with fecal tests. Nationwide, only about 67% of adults in this age range were current with screening, the study found.

At the state level, screening rates ranged from a low of 59% in Wyoming to a high of 75% in Massachusetts.

Researchers found even greater variability within some states. Screening rates were lowest in one county in Alaska, at just 40%, and highest in one county in Florida, at 80%.

The widest gap among counties was in South Dakota, with a 29-percentage point difference between the counties with the lowest and highest screening rates; the smallest gap was in Connecticut, with about 4 percentage points separating the counties with the highest and lowest screening rates.

"We anticipated variations by county in colorectal cancer screening within the states because of different educational and income levels and geographical inequalities, but we were still struck by differences of more than 20 percentage points between counties in some states," said lead study author Zahava Berkowitz, of the National Center for Chronic Disease Prevention and Health Promotion, at the U.S. Centers for Disease Control and Prevention in Atlanta.

For the current study, researchers modeled county level screening rates by using CDC survey data for 251,360 adults aged 50 to 75 and looking at U.S. population estimates for 3,142 counties nationwide.

Screening varied by ethnicity, with about 69% of white adults current on recommended screenings, compared with 57% of Hispanics, the study found.

One limitation of the study is that researchers relied on survey participants to accurately recall and report their screening exams, and inaccurate responses might throw off the estimated screening rates, researchers noted March 1 online in Cancer, Epidemiology, Biomarkers and Prevention.

The study also doesn't offer insight into why so many people are not current with their recommended screenings, and there are many factors that can contribute to this, said Electra Paskett, a cancer researcher at Ohio State University in Columbus who wasn't involved in the study.

Screening rates tend to be lowest in places that don't have polices to cover these tests for everyone or don't have providers in the community who can do the tests, Paskett said by email. Doctors also might not recommend screening, or people might not want it or want to travel too far to get it.

"All of these act and interact in different ways to keep people from screening," Paskett added. "It matters because colorectal cancer is totally preventable as is death from colorectal cancer if people get screened regularly."

SOURCE: https://bit.ly/2GkLQn0

Cancer Epidemiol Biomarkers Prev 2018.