NEW YORK (GenomeWeb) – Researchers from the Impact of Personal Genomics (PGen) study have found that nearly 6 percent of customers who use direct-to-consumer personal genetic testing (DTC-PGT) services made changes to their prescription medication based on their test results.
PGen has reported several important results over the past few years, including a study from 2013 that looked into the emotional and practical impacts of DTC testing and a study from 2015 that reported that consumers understood basic genetic concepts after testing. The researchers also published several studies earlier this year, including one published in March that revealed that consumers feel less confident in their genetic knowledge after they receive their results.
For this study, the PGen study researchers surveyed two US companies that provide DTC-PGT services, 23andMe and Pathway Genomics. Both companies have since modified the services they offer based on warnings and investigations from the US Food and Drug Administration. The companies allowed for some of their customers to be surveyed to determine their reactions to genetic risk information.
The researchers recruited 1,648 customers — 1,085 from 23andMe and 563 from Pathway Genomics — to fill out surveys before they received their test results. The team also sent follow-up surveys two weeks and then six months after the customers received results. These were returned by 1,464 customers — 947 from 23andMe and 517 from Pathway Genomics. As they reported in Genetics in Medicine, the researchers specifically looked into changes customers made based to their prescription medications based on pharmacogenetic results of DTC-PGT.
Customers of 23andMe received eight pharmacogenomic results which presented relative risks or benefits for treatment compared with someone in the general population of the same ethnicity. Pathway customers received up to nine pharmacogenetics results presented as either "normal," "beneficial effect," or "adverse effect."
The researchers conducted statistical analysis using SAS 9.3 on data from participants who submitted baseline and six-month surveys, as well as complete data on age, gender, race/ethnicity, education, self-reported health, interest in pharmacogenomics PGT results, baseline prescription medication use, and changes to prescription medications after PGT.
Of the 961 participants who reported their pharmacogenomics results to the researchers, 54 participants (5.6 percent) reported changing a prescription medication they were already using or starting a new medication by the six-month follow-up. The researchers noted that of those 54 participants, 46 participants reported consulting a healthcare provider before making prescription changes. They also reported that among the 537 participants who reported baseline use of prescription medication, 39 of them (7.3 percent) reported a change to a prescription medication they were already using and 34 of them reported consulting a healthcare provider.
"The potential utility of pharmacogenomic results is limited by the pharmacological treatment needs of a particular individual at particular time," the researchers wrote. "This may explain, in part, why so few participants — relative to the 91.2 percent receiving a positive pharmacogenomic result and to the 49 percent who predict using their results to guide future medication decisions — reported changing a prescription medication in our study."
The PGen researchers concluded that while there are consumers of DTC-PGT that made changes in the six month period after they received results, it was a proportionally small number of them, and their reasoning for making these decisions is not yet well understood. "Further investigation of how physician consultation during the post-PGT period motivates or discourages such changes is warranted," the authors added.