Background Direct-to-consumer (DTC) genomic testing has generated controversy, however the actual impact of testing on consumer behaviour has been understudied, particularly for pharmacogenomic (PGx) testing.

Methods We recruited a sample of adults who purchased a DTC genomic test and had previously received their genomic test results for complex disease risk. All participants additionally underwent PGx testing. At follow-up, to assess the impact of PGx testing on consumer behaviour, healthcare utilisation and psychological status were compared between approximately a third of participants who had received their PGx results and the remaining two-thirds of participants who were still awaiting results. The PGx test included genetic testing for drug effectiveness or risk of side effects for 12 medications.

Results At follow-up, there were 481 PGx test recipients and 844 non-recipients still awaiting results. PGx test recipients had more physician visits (p=0.04) and were more likely to share their results with their physician (p=0.001). Both groups showed a decrease in anxiety symptoms from baseline to follow-up, with a trend for PGx recipients to show less of a decrease compared with non-recipients (p=0.10). PGx recipients were more likely to report that their physician ordered additional tests (p=0.01) based on their genomic test. There were no group differences in follow-up test-related distress (p=0.67).

Conclusions DTC PGx risk profiling among a selected sample of individuals was associated with increased physician utilisation and did not result in any adverse changes in psychological health or follow-up test-related distress.