The effect of pharmacogenetic profiling with a clinical decision support tool on healthcare resource utilization and estimated costs in the elderly exposed to polypharmacy.

OBJECTIVE To compare healthcare resource utilization (HRU) and clinical decision-making for elderly patients based on cytochrome P450 (CYP) pharmacogenetic testing and the use of a comprehensive medication management clinical decision support tool (CDST), to a cohort of similar non-tested patients. METHODS An observational study compared a prospective cohort of patients ≥65 years subjected to pharmacogenetic testing to a propensity score (PS) matched historical cohort of untested patients in a claims database. Patients had a prescribed medication or dose change of at least one of 61 oral drugs or combinations of ≥3 drugs at enrollment. Four-month HRU outcomes examined included hospitalizations, emergency department (ED) and outpatient visits and provider acceptance of test recommendations. Costs were estimated using national data sources. RESULTS There were 205 tested patients PS matched to 820 untested patients. Hospitalization rate was 9.8% in the tested group vs. 16.1% in the untested group (RR = 0.61, 95% CI = 0.39-0.95, p = 0.027), ED visit rate was 4.4% in the tested group vs. 15.4% in the untested group (RR = 0.29, 95% CI = 0.15-0.55, p = 0.0002) and outpatient visit rate was 71.7% in the tested group vs. 36.5% in the untested group (RR = 1.97, 95% CI = 1.74-2.23, p < 0.0001). The rate of overall HRU was 72.2% in the tested group vs. 49.0% in the untested group (RR = 1.47, 95% CI = 1.32-1.64, p < 0.0001). Potential cost savings were estimated at $218 (mean) in the tested group. The provider majority (95%) considered the test helpful and 46% followed CDST provided recommendations. CONCLUSION Patients CYP DNA tested and treated according to the personalized prescribing system had a significant decrease in hospitalizations and emergency department visits, resulting in potential cost savings. Providers had a high satisfaction rate with the clinical utility of the system and followed recommendations when appropriate.