It's time for a health checkup, and your primary care provider offers you genetic testing to find out if you have an increased risk of certain diseases or conditions. With the increasing availability of affordable genetic tests, such a scenario is more likely in the near future, if it hasn't occurred already. Learning about genetic testing and its uses may help prepare you for a conversation with your provider about whether genetic testing is right for you.
Two articles published in the May issue of the journal Health Affairs provide insights on the recent exponential growth in the number of genetic tests and the views of primary care providers on testing patients for genetic risks.
Authors of the first Health Affairs report used recent data on genetic test availability and insurance claims to get a current view of the genetic testing landscape and to examine test availability and spending. They specifically looked at the rapid growth in genetic testing and spending between 2014 and 2017. This growth is a result of the increased role genetic testing plays in personalized medicine and the scientific advances that have reduced the cost of DNA sequencing. With an estimated 75,000 tests on the market today—that's about 10 new tests per day—the amount of health information available to patients and their healthcare providers is remarkable.
Overall, the authors saw growth in the number of and the spending on genetic tests that evaluate more than one gene at a time, with a majority of paid insurance claims coming from prenatal testing, including noninvasive prenatal genetic testing/screening (NIPT/NIPS) and carrier screening (33% to 43% of spending). NIPT/NIPS uses a blood sample taken from a pregnant woman to screen for chromosome disorders in her developing baby by examining placental DNA in the mother's blood. The authors suspect that NIPT/NIPS has become more popular and increasingly approved by insurance companies because other prenatal screening methods are less sensitive.
Tests for hereditary cancers were second to NIPT/NIPS for total spending (30%). BRCA gene mutation testing is a well-known hereditary cancer genetic test that assesses a person's risk of developing breast, ovarian or prostate cancer associated with hereditary mutations in the BRCA1 or BRCA2 genes.
Tests for oncology diagnostics and treatment (used to prescribe anti-cancer drugs based on cancer biomarkers) accounted for about 10% of spending, while pharmacogenetic tests (used to choose optimal drugs or drug dose for people based on their genetics) accounted for less than 5% of spending.
With this dramatic growth in genetic testing, more patients may be offered this kind of testing by their primary care providers. However, the Health Affairs authors say that the vast array of genetic tests could also "add to the difficulties for doctors to figure out which tests are appropriate and worth the price, and also make sure doctors can translate the results into meaningful information for patients."
The second report published in Health Affairs surveyed primary care providers (family physicians, nurse practitioners, general internists, physician assistants, and residents) on the challenges they may face when offering genetic tests and explaining results to their patients. The survey was conducted as part of a study in which the primary care providers enrolled patients of African ancestry and offered them genetic testing to determine whether they may have an increased risk for kidney disease. Specifically, the survey included 488 primary care providers in New York City who were about to enroll patients in the study and asked them about their knowledge of genetic tests and genetic test use with their patients.
Most of the surveyed primary care providers reported having a positive view of genetic testing and 70% agreed that genetic testing would generally improve the health of patients within the next five years. However, only one-third of them used or referred patients for genetic testing in the past year. About 40% of the primary care providers felt knowledgeable about genetic links to disease, and only 14% felt comfortable interpreting results for their patients. Most of the providers responded that they want resources to help their patients navigate the genetic testing process. Examples include resources on how to talk to their patients about genetics and genetic testing, patient handouts, and information on how to manage patients with positive results.
As genetic testing continues to expand, patients who are offered genetic testing will require resources too. Not all genetic testing is useful for everyone and, depending on the specific case, genetic testing may not be covered by a person's health insurance. Individuals will need to decide, with the help of their providers, whether genetic testing in right for them. People faced with decisions about genetic testing or who simply want to learn more about genetics and the testing process can turn to resources like National Society of Genetic Counselor's Patient Resource Site and the U.S. National Library of Medicine's Genetics Home Reference.