Trends in Positive BRCA Test Results Among Older Women in the United States, 2008-2018

Genetic testing for BRCA1/2 pathogenic variants has been used for targeted, individualized cancer prevention and treatment. A positive BRCA test result indicates a higher risk for developing BRCA-related cancers. During the past decade, testing criteria have loosened. The impact of these loosened criteria on BRCA testing in older women has not previously been studied.

To assess whether the rate of positive BRCA test results changed between 2008 and 2018 among older women in the United States.

This cross-sectional study used a 10% random sample of women 65 years of age or older from Optum's deidentified Integrated Claims-Clinical data set (2008-2018), a large national electronic health record data set. A total of 5533 women with BRCA test results from January 1, 2008, to March 31, 2018, were evaluated.

Annual percentage change in positive BRCA test results was evaluated. Multivariable logistic regression models were used to assess the association between positive test results and race/ethnicity, region of residence, income, educational level, and personal history of breast or ovarian cancer.

Of 5533 women 65 years of age or older (mean age, 68.1 years [95% CI, 67.9-68.4 years]) who underwent BRCA testing from 2008 to 2018, most (4679 [84.6%]) were non-Hispanic White women, and 1915 (34.6%) resided in the Midwest. Positive BRCA test results decreased from 85.7% (36 of 42) in 2008 to 55.6% (140 of 252) in 2018 (annual percentage change, -2.55; 95% CI, -3.45 to -1.64). Among patients with breast or ovarian cancer, positive test results decreased from 83.3% (20 of 24) in 2008 to 61.6% (61 of 99) in 2018, while among women without breast or ovarian cancer, positive test results decreased from 87.5% (21 of 24) in 2008 to 48.4% (74 of 153) in 2018 (annual percentage change, -3.17 vs -2.49; P = .29). Women with positive test results were more likely to be non-Hispanic Black women, to live in the West or South, to live in areas with a low percentage of college graduates, or to not have a personal history of breast or ovarian cancer.

This study suggests that there was a significantly decreasing rate of positive BRCA test results among women 65 years of age or older. Socioeconomic and regional disparities in testing use remain an issue.