Hyrum Wright and Karen Whitt, College of Nursing

Introduction

Pharmacogenetics is the study of the relationship between genetics and the metabolism of medications. Some classes of drugs have been shown to be metabolized differently in people of specific genetic profiles, with gene markers correlating to the differences in metabolism. For example, patients taking simvastatin have a modest increase in myopathy risk even with lower doses of simvastatin if they have the C allele at SLCO1B1 rs4149056, compared with other alleles. This would be significant to the provider who prescribes a statin drug to patients. The provider, ideally, would be aware that certain patients have an increased risk for myopathy and would encourage the patient to obtain a genetic screening. This screening would then be used to adjust the dose of the drug, if necessary. Many allele variations have been found to have pharmacological ramifications and prescribers are better able to serve their clients when they are aware of the risks and can access the clients’ genetic profiles. The differences in metabolism can range from more rapid metabolism of a drug, slower metabolism of a drug, and outright contraindications for a drug. A contraindication is a reason for which a drug should not be given to a patient, such as an allergy or hypersensitivity. Some drugs are never given to certain types of patients, the risks outweighing potential benefits.

We wanted to investigate whether providers are aware of and using the pharmacogenetic resources available to them. Although the guidelines are publicly available (see pharmgkb.org), not all drugs have pharmacogenetic evidence, at this time. The field is still developing and it is believed that some providers may not be prescribing according to pharmacogenetic guidelines and may need basic education about them.

Methodology

Information was collected on the prescribing practices of Nurse practitioners at a gathering of practitioners in June 2015. Specifically, the utilization of pharmacogenetic principles in prescribing and the level of experience with pharmacogenetics were evaluated. Participants were asked to rate their knowledge of pharmacogenetics on a scale of 1 to 10, 1 meaning no knowledge of pharmacogenetics and 10 meaning extremely knowledgeable. Participants were also asked about the types of medications prescribed based on pharmacogenetics and whether their current electronic health record system had the means to provide support to clinical decisions based on pharmacogenetics. This information was then to be analyzed and presented.

Results

It was found that 20 percent of the nurse practitioners were prescribing according to pharmacogenetic profiles of the patients. 22 different types of medications were listed as being prescribed with consideration of pharmacogenetics. Only 7.7 percent of participants reported that their current electronic health record systems included clinical decision support reminders of pharmacogenetic implications. The mean self-reported knowledge rating of pharmacogenetics among those surveyed was 3.6 on a 1 to 10 scale.

Discussion

Review of others’ research shows that lack of familiarity with pharmacogenetics is not unique to one practitioner population. Our research indicates, and others may be seen to support that pharmacogenetic education would be beneficial to prescribers, to better allow them to meet the needs of their patients. The low percentage of practitioners who use pharmacogenetics in their prescribing practices does not reflect the lack of possible prescription tools, but rather the health record systems’ lack of inclusion of available information. One may speculate as to the reasons for which clinicians do not use pharmacogenetics regularly, but further study would be required to accurately assign cause. It is notable, however, that the health records systems do not provide support for those wishing to use pharmacogenetics in prescription. The benefits of pharmacogenetics are significant to patients’ wellbeing and are growing in scope.

Conclusion

The field of pharmacogenetics is continuously growing and research is being conducted to discover more genetic markers and their connections to medication metabolism. The strength of prescription guidelines varies from drug to drug, but many drugs already have guidelines with significant evidence to support them. This information is helpful to clinicians, but many clinicians are unaware of its importance. Our research should serve to highlight this deficit and help increase awareness of pharmacogenetics as a field. Many clinicians admit to their unfamiliarity with pharmacogenetics and efforts to educate them in the fields of pharmacogenetics and genetics, in general, would be helpful in increasing the use of pharmacogenetics in prescription. Those wishing to learn more about specific gene markers and prescription considerations may visit pharmgkb.org. References to the presentations and publications based on our research are included below.

Presentations

Whitt, K. J., Wright, H., & O’Brien, T. J. (2016, March, 10). Utilization of pharmacogenetics profiles as a basis for prescribing by nurse practitioners. American College of Medical Genetics, Annual Clinical Genetics Meeting, Tampa, FL

Whitt, K. J., Wright, H., & O’Brien, T. (2016, September, 15). Nurse practitioners’ use of pharmacogenetics in clinical practice. Abstract of distinction and top-rated podium presentation at the Council for the Advancement of Nursing Science, State of the Science Congress on Nursing Research. Washington, DC.

Publications

Whitt, K. J., Wright, H., & O’Brien, T. (In Review) Nurse practitioners’ utilization and knowledge of pharmacogenomics for prescribing in clinical practice. The Pharmacogenomics Journal.