Pharmacogenetics in Psychiatry: Perceived Value and Opinions in a Chilean Sample of Practitioners

Pharmacogenetics of selective serotonin reuptake inhibitors (SSRI): A serotonin reuptake transporter (SERT)-based approach

Neuropsychiatric disorders are considered to be the most common cause of disability worldwide. Serotonin and its transporter is a prominent paradigm in mood disorders. Response to selective serotonin reuptake inhibitors (SSRI) is altered due to heterogeneity in the serotonin transporter gene, SLC6A4 (solute carrier family 6 member 4). The reported polymorphisms are found to be in different regions of the transporter gene: promoter region (5-HTTLPR and various single nucleotide polymorphisms within it), intron (STin2), and exon 9 (I425V). The long and short alleles of the 5-HTTLPR gene, which are prevalent among variations, may mediate differential effects. In long allelic variant carriers, an increased response to SSRI and timely recovery is due to increased availability of SERT. Whereas, SERT availability is significantly decreased in short allelic carriers, necessitating a reduction in SSRI dosage due to the increased risk of adverse drug reactions. Thus, pharmacogenetic investigations are required to understand the impact of functional variations on the efficacy and tolerability of SSRI. Identifying the carrier variants may aid in clear-decision making of the treatment regimen, aiding the approach of personalized medication.

User Experiences of Pharmacogenomic Testing and Opinions among Psychiatry Patients

Pharmacogenomic testing (PGx) is a tool used to guide physicians in selecting an optimal medication for clients based on their genetic profile. The objective of this qualitative study is to understand patients' experiences with PGx testing as well as their opinions regarding the clinical adoption of such tests in psychiatry. A focus group was conducted to assess the needs of clients who had experience using a PGx test. Participants were recruited from a large study on PGx testing that offered physicians an opportunity to use PGx reports to guide psychotropic prescriptions. The focus group discussions were recorded, transcribed, and coded using NVivo to identify core themes. A total of 11 people participated in the focus group. Our analysis revealed that many participants were in favour of implementing PGx testing in psychiatric practice, and all expressed important considerations for patient-centred optimization of PGx testing. The main themes captured were: education and awareness among clinicians, cost considerations, PGx results-sharing and accessibility, and prospective benefits. The results of this study suggest that patients are keen to see PGx testing in widespread clinical care, but they report important opportunities to improve knowledge mobilization of PGx testing.

Perspectives on the Clinical Use of Pharmacogenetic Testing in Late-Life Mental Healthcare: A Survey of the American Association of Geriatric Psychiatry Membership

OBJECTIVE

To assess perspectives on pharmacogenetic (PGx) testing among members of the American Association of Geriatric Psychiatry (AAGP).

DESIGN

Cross-sectional survey.

PARTICIPANTS

Members of the AAGP.

MEASUREMENTS

Anonymous web-based survey consisting of 41 items covering experiences, indications, barriers, facilitators and ethical, legal and social implications for PGx testing.

RESULTS

A total of 124 surveys were completed (response rate = 13%). Most respondents (60%) had used PGx testing but an equal proportion (58%) was uncertain about the clinical usefulness of PGx testing in late-life mental health. Despite self-reported confidence in the ability to order and interpret PGx testing, 60% of respondents felt there was not enough clinical evidence for them to use PGx testing in their practice. This was compounded by uncertainties related to their ethical obligation and legal liability when interpreting and using (or not using) PGx testing results. Respondents strongly affirmed that clinical and legal guidelines for PGx testing in older adults are needed and would be helpful.

CONCLUSION

The findings suggest additional PGx research and physician education in late-life mental healthcare settings is required to reconcile uncertainties related to the clinical efficacy and ethico-legal aspects of PGx testing as well as address current knowledge barriers to testing uptake. These efforts would be further facilitated by the development of clinical practice guidelines to ensure equitable access to testing and standardized implementation of PGx-informed prescribing in older adults.

Pharmacogenetic Testing Knowledge and Attitudes among Pediatric Psychiatrists and Pediatricians in Alberta, Canada

OBJECTIVE

To assess knowledge, attitudes, and barriers as well as ethical, legal and social concerns towards pharmacogenetic (PGx) testing among pediatric psychiatrists and pediatricians in Alberta, Canada.

METHOD

An anonymous electronic survey was sent to pediatric psychiatrists (n = 49) and pediatricians (n = 93) in Alberta.

RESULTS

A total of 20 surveys were completed (response rate = 14%). Respondents agreed that PGx testing is clinically useful and a majority believed testing had the potential to aid in medication selection, dosing, switching, augmentation, and deprescribing, particularly among children with treatment-resistant conditions. However, most respondents could not identify an appropriate lab to perform testing, did not have the necessary training to interpret PGx results, and did not have access to experts that could assist them in interpreting results.

CONCLUSION

The findings suggest additional PGx education and training is required to boost self-efficacy and uptake of PGx testing among pediatric psychiatrists and pediatricians in Alberta, Canada. In addition, local and global efforts to develop clinical practice guidelines, provide clear legal guidance, and ensure equitable access to testing may facilitate the implementation of PGx-informed prescribing.