In recent years, testing for the BRCA1
gene mutations has increased among women in both metropolitan and nonmetropolitan areas, helping to drastically reduce the gap in testing rates between the groups.
A new CDC Surveillance Summary
presents the rates of BRCA
testing from 2009 to 2013 among women aged 18 to 64 with employer-sponsored health insurance. Specifically, it compares metropolitan and non-metropolitan areas in terms of their rates of testing, as well as the receipt of preventive interventions and genetic counseling after getting the test.
Testing for BRCA
mutations has been identified as a method for earlier detection or prevention of cancer through enhanced screenings and preventive surgeries. BRCA
status can also help guide treatment decisions for women diagnosed with cancer. Although organizations like the US Preventive Services Task Force (USPSTF) and the National Comprehensive Cancer Network recommend testing for women who could benefit based on family history, little research exists on how rates of testing may vary nationwide.
For the Surveillance Summary, the researchers used a commercial claims database to compare rates of testing, preventive interventions, and genetic testing over time and by census region. In each year, the number of women included in the database ranged from 15 to 20 million.
From 2009 to 2014, BRCA
testing rates increased 2.3-fold in metropolitan areas and 3-fold in nonmetropolitan ones. In 2009, the relative difference in testing rates between the 2 areas had been 36.9%, but by 2014 it had decreased by nearly half to 19.6%. Still, urban women were more likely to receive the test than their rural counterparts during each year, for all test subgroups and across all age groups.
Rates of mastectomy after BRCA
testing were comparable among the urban and rural areas, but women in metropolitan areas were generally more likely to receive genetic counseling or a breast magnetic responance imaging after the test.
The study authors noted that the lower rates of testing and follow-up in nonmetropolitan areas could reflect difficulties in accessing specialists like genetic counselors. However, the patterns of increasing testing rates over time in rural areas may indicate that more women began to seek genetic testing and counseling from their primary care providers. This may have been encouraged by the 2013 recommendation
from the USPSTF that trained providers should provide counseling about BRCA
testing to at-risk women.
Despite the limitation that the study’s focus on commercially-insured women may have overestimated testing rates, the researchers wrote that the data provide a useful starting point for public health officials looking to monitor patterns in BRCA
testing and follow-up rates. These trends can be used to inform interventions targeting certain women, such as those in nonmetropolitan areas.
“Programs can build on the recent decrease in geographic disparities in receipt of BRCA
testing while simultaneously educating the public and health care providers about [USPSTF] recommendations and other clinical guidelines for BRCA
testing and counseling,” the study authors concluded.