The Value of Using Pharmacogenetic Risk Scores in Routine Practice

Conducting genetic tests for variants of drug metabolizing enzyme (DME) is a potential option for personalizing medication prescribing, optimizing patient outcomes, and reducing healthcare resource utilization and costs.

Researchers assessed the clinical utility and value of this preemptive pharmacogenetic test. The results of the study were presented at the AMCP Annual Meeting during a poster session titled “Optimizing the Value of Pharmacogenetic Risk Screening Among Patients with Polypharmacy: A Healthcare System Experience.”

This cross-sectional study included 559,445 patients of all age groups who visited the University of Utah Healthcare and were included in the electronic data warehouse medical/pharmacy claims. They included patients who were taking three prescription drugs (one metabolized by a polymorphic DME) from June 1, 2015, to December 31, 2016.

In this cohort, 236,822 patients (42%) were on one of the targeted drugs for genetic testing; of these, 54,509 patients met the full eligibility criteria. The mean patient age was 48 (standard deviation, 19 years), 42% were male, and 84% were white.

Approximately 40% of the study population were taking at least one prescription drug metabolized by a polymorphic DME.

Among the top 10 drugs across all age groups with major DME susceptibility were pain medications (tramadol and codeine) and antidepressants (citalopram, escitalopram, amitriptyline, nortriptyline, and paroxetine).

Younger patients (≤29 years) were more likely to be prescribed oral contraceptives (25%), while older patients (50-64 years) were more likely to be prescribed hormone replacement therapy (12%).

The frequency of clopidogrel use increased with age group (3% among ≤29 years vs 17% among ≥65 years).

The trend of the genetic risk increased with age in the following clinics:

• Cardiology
• Endocrinology
• Surgery
• Emergency medicine

“This information is important in identifying the right cohort for a pragmatic clinical trial, so appropriate outcomes measures can be identified in a population to determine the value of incorporating pharmacogenetic risk scores in routine clinical practice,” the researchers concluded.

Biltaji E, Biskupiak J, Sherwin C, McMillin G, Brixner D. Optimizing the Value of Pharmacogenetic Risk Screening Among Patients with Polypharmacy: A Healthcare System Experience. Abstract U50. Presented at the AMCP Managed Care & Specialty Pharmacy Annual Meeting, April 23-26; Boston, MA.