Recent advancements in pharmacogenomics, the study of how a patient’s genes affect their response to certain medications, could have major implications for both patients and providers. Typically, personalized technology can have a large financial burden on patients; however, these techniques are becoming more available and affordable with results that have significant impacts on patient care. Here we discuss a patient with treatment resistant mood disorder from Alzheimer’s Dementia.

Patient is an 89-year-old female with hypothyroidism and Alzheimer’s dementia. Mood control for depression, anxiety, and insomnia had been difficult due to lack of efficacy of numerous medications and intolerable side effects. She was intolerant to Mirtazapine due to paradoxical increased stimulation at night. Bupropion also resulted increased stimulation with insomnia, confusion, and anxiety. Alprazolam caused disequilibrium, resulting in frequent falls. The most successful medication for mood control was Sertraline 150 milligrams, which worked for years until she developed hyponatremia, prompting discontinuation and reinitiation at 25 milligrams. Due to these difficulties, we pursued psychotropic pharmacogenetic testing through GeneSight®. Results of genetic testing showed that she is a poor metabolizer of CYP2D6 indicating the need for a low dose of Quetiapine which she was prescribed with good outcomes for nighttime activity. She is an intermediate metabolizer of CYP3A4 requiring a higher dose of Sertraline, which was consistent with past successful dosing. She is heterozygous for the short/long promoter polymorphism of the serotonin transporter gene; therefore, she may have a moderately decreased response to certain SSRIs due to the presence of the short form of the gene.

The progression of pharmacogenetics and the ease of use, opens up the exciting possibility of higher efficacy therapy through tailored treatment. These techniques are financially accessible and easy to collect. A physician orders the kit which is sent to the patient, who swabs their cheek and mails back the sample. Results are sent to the physician within a week. Testing is covered by most insurances and Medicaid and is free for patients with Medicare part B. The results of these test can expedite care by eliminating trial and error dosing, ultimately leading to faster, safer outcomes.

References and Resources

1. Oslin, D. W., Lynch, K. G., Shih, M. C., Ingram, E. P., Wray, L. O., Chapman, S. R., Kranzler, H. R., Gelernter, J., Pyne, J. M., Stone, A., DuVall, S. L., Lehmann, L. S., Thase, M. E., PRIME Care Research Group, Aslam, M., Batki, S. L., Bjork, J. M., Blow, F. C., Brenner, L. A., Chen, P., … Wood, A. E. (2022). Effect of Pharmacogenomic Testing for Drug-Gene Interactions on Medication Selection and Remission of Symptoms in Major Depressive Disorder: The PRIME Care Randomized Clinical Trial. JAMA, 328(2), 151–161. https://doi- org.ummc.idm.oclc.org/10.1001/jama.2022.9805
2. Forester, B. P., Parikh, S. V., Weisenbach, S., Ajilore, O., Vahia, I., Rothschild, A. J., Thase, M. E., Dunlop, B. W., DeBattista, C., Conway, C. R., Shelton, R. C., Macaluso, M., Li, J., Traxler, P., Logan, J., Brown, L., Dechairo, B., & Greden, J. F. (2021). Combinatorial Pharmacogenomic Testing Improves Outcomes for Older Adults With Depression. Focus (American Psychiatric Publishing), 19(1), 76–85. https://doi- org.ummc.idm.oclc.org/10.1176/appi.focus.19107