The use of pharmacogenomics in the treatment of major depressive disorder (MDD) is supported by study data published in the Journal of Psychiatry Research.
Researchers designed an open-label prospective study to examine the efficacy of pharmacogenomics for patients with MDD in both psychiatric and primary care settings. Pharmacogenomic testing was performed for all patients at baseline (N=1871), using genomic DNA isolated from buccal swabs. Medications were classified as congruent or incongruent via genotyping results. Depressive symptoms were assessed at baseline and at 8 to 12 weeks’ follow-up using the Beck Depression Inventory (BDI).
The total patient cohort experienced a 27.9% reduction in depressive symptoms at follow-up, as well as response (≥50% decrease in BDI score) and remission (BDI score ≤10) rates of 25.7% and 15.2%, respectively. Patients treated by primary care providers had significantly improved symptom reduction rates (31.7% vs 24.9%), response rates (30.1% vs 22.3%), and remission rates (19.5% vs 12.0%) compared with patients treated by psychiatrists (P <.01 for all). Additionally, 16.4% of patients taking medications congruent with their combinatorial pharmacogenomic test experienced remission compared with just 13.9% of patients taking ≥1 incongruent medication (P =.039). Patients taking congruent medications experienced an overall 31% relative improvement in response rate compared with patients taking incongruent medications. Patients treated by primary care providers experienced slightly higher rates of congruence (87.6%) compared with patients treated by psychiatrists (85.2%), though the difference was not statistically significant.
Researchers noted that the discrepancy in treatment responses across provider types may result from the higher rates of psychiatric comorbidities in patients treated by psychiatrists.
These data support the clinical use of combinatorial pharmacogenetics for patients with MDD. Patient improvement across provider types also suggests that pharmacogenetics may have use in broader treatment settings.
Tanner J-A, Davies PE, Voudouris NC, et al. Combinatorial pharmacogenomics and improved patient outcomes in depression: treatment by primary care physicians or psychiatrists. J Psychiatr Res. 2018;104:157-162.