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

Importance: 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. Objective: To assess whether the rate of positive BRCA test results changed between 2008 and 2018 among older women in the United States. Design, Setting, and Participants: 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. Main Outcomes and Measures: 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. Results: 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. Conclusions and Relevance: 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.