Real-World Impact of Pharmacogenomic Testing on Medication Use and Healthcare Resource Utilization in Patients With...

Pharmacogenomic (PGx) testing can help improve response and remission rates for patients with major depressive disorder (MDD) and at least one treatment failure. To investigate real-world outcomes, we examined 1) significant gene-drug interactions (GDIs) and 2) healthcare resource utilization (HRU) in a large US insurance claims dataset.

Weighted multigene PGx testing results in adult patients with MDD were linked with deidentified US claims data. The PGx test report organized medications as congruent (no known or moderate GDI) or incongruent (significant GDI). Medication claims data before and after PGx testing was used to categorize patients as no change in congruency, incongruent-to-congruent, or congruent-to-incongruent. HRU (hospitalizations and emergency department visits) was compared in the 180 days before and after PGx testing.

A total of 20,933 patients met inclusion criteria; 16,965 of whom filled medication prescriptions before and after PGx testing. After PGx testing, the proportion of patients filling prescriptions with significant GDIs was reduced (26.1% pretesting vs 15.9% posttesting). All HRU was significantly reduced ( P  < 0.001) after PGx testing except for nonpsychiatric hospitalizations ( P  > 0.05). Psychiatric hospitalizations were significantly reduced after PGx testing in the incongruent-to-congruent and no change in congruency categories ( P  < 0.001), but not in the congruent-to-incongruent category. Conversely, emergency department visits were significantly reduced after PGx testing in all congruency categories ( P  < 0.005) and did not differ when compared across congruency categories.

After PGx testing, patients with MDD had decreased prescribing of medications with significant GDI and reduced HRU. PGx testing may have influenced these outcomes, but the retrospective study design limits clarity on its impact.