In 2009, the U.S. Preventive Services Task Force revised its mammography screening guidelines, recommending that routine breast cancer screening should begin at age 50 instead of age 40. They suggested an individualized approach for women between the ages of 40 and 49 and cited insufficient evidence for screening women aged 75 and older.
Researchers at the University of Vermont Cancer Center, Sarah Nowak, PhD, and Brian Sprague, PhD, discovered that the change in guidelines led to an unintended decline in mammography screening rates for all three age groups, including the 50-74 age group, who are most at risk of developing breast cancer and in greatest need of screenings. The researchers called this effect “spillover,” as the new guidelines aimed to reduce unnecessary screening for less at-risk groups but inadvertently affected at-risk women as well.
Their findings were published in The American Journal of Preventative Medicine, showing data from 2002 to 2018. The data revealed that after the 2009 guideline change, national screening rates dropped by 1.3 percentage points per year for ages 40-49, 0.5 percentage points per year for women aged 50-74, and 1.7 percentage points per year for those 75 and older.
Dr. Sprague explained that although these percentages may seem small, the cumulative impact over a decade means that 2.4 million fewer women in the United States aged 50-74 are up to date with screening mammography.
The research team is now investigating the reasons behind the spillover effect. One possible explanation is that women are more likely to encourage others to get screened when they personally know someone diagnosed with breast cancer through screening. The declining screening rates for women aged 40-49 and 75 and older could lead to fewer women in the 50-74 age group hearing about early-stage breast cancer diagnoses in their friends and family, thus reducing their motivation to get screened.
Key Takeaways in a Nutshell – Health Newstrack
– In 2009, the U.S. Preventive Services Task Force revised mammography screening guidelines, recommending routine breast cancer screening to start at age 50 instead of 40, with an individualized approach for women aged 40-49.
– Researchers found that the change in guidelines led to an unintended decline in mammography screening rates across all age groups, including women aged 50-74, who are most at risk of developing breast cancer.
– This unintended effect, called “spillover,” meant that 2.4 million fewer women aged 50-74 in the United States were up to date with screening mammography over a decade.
– The research team is currently exploring the reasons behind the spillover effect, with one possibility being that women are less likely to encourage others to get screened if they don’t personally know someone diagnosed with breast cancer through screening.