Table 10. Predictors Associated with Uptake of Genetic Testing (GT) continued...
Uptake of genetic counseling and genetic testing in diverse populations
Degree of uptake of genetic counseling and genetic testing in diverse populations
There are limited data on uptake of genetic counseling and testing among nonwhite populations, and further research will be needed to define factors influencing uptake in these populations. The uptake of BRCA testing appears to vary across some racial/ethnic groups. A few studies have compared uptake rates between African American and white women.[14,37] In a case-control study of women who had been seen in a university-based primary care system, African American women with family histories of breast cancer or ovarian cancer were less likely to undergo BRCA1/2 testing than were white women who had similar histories. In another study among breast cancer patients who were counseled about BRCA1/2 risk in a clinical setting, lower uptake was reported among African American women than among white women.
Notably, the racial differences observed in these studies do not appear to be explained by factors related to cost, access to care, risk factors for carrying a BRCA1 or BRCA2 mutation, or differences in psychosocial factors, including risk perceptions, worry, or attitudes toward testing.
Factors influencing uptake of genetic counseling and genetic testing in diverse populations
Several studies have examined uptake or "acceptance" of BRCA testing among African Americans enrolled in genetic research programs. Among study enrollees from an African American kindred in Utah, 83% underwent BRCA1 testing. Age, perceived risk of being a carrier, and more extensive cancer knowledge predicted testing acceptance. Another study that recruited African American women through physician and community referrals reported a BRCA1/2 testing acceptance rate of 22%. Predictors of test acceptance included having a higher probability of having a mutation, being married, and being less certain about one's cancer risk. Finally, a third study that recruited at-risk African American women from an urban cancer screening clinic found that acceptors of BRCA testing were more knowledgeable about breast cancer genetics and perceived fewer barriers to testing, including negative emotional reactions, stigmatization concerns, and family-related guilt. While these are independent predictors of genetic testing uptake, they do not explain the disparities in testing uptake across different ethnic groups. What may explain these differences are several attitudes and beliefs held about testing by individuals from diverse populations.