Integrating pharmacogenetic information and clinical decision support into the electronic health record

Abstract

Pharmacogenetics (PG) examines gene variations for drug disposition, response, or toxicity. At the National Institutes of Health Clinical Center (NIH CC), a multidepartment Pharmacogenetics Testing Implementation Committee (PGTIC) was established to develop clinical decision support (CDS) algorithms for abacavir, carbamazepine, and allopurinol, medications for which human leukocyte antigen (HLA) variants predict severe hypersensitivity reactions. Providing PG CDS in the electronic health record (EHR) during order entry could prevent adverse drug events. Medical Logic Module (MLM) programming was used to implement PG CDS in our EHR. The MLM checks to see if an HLA sequence-based gene test is ordered. A message regarding test status (result present, absent, pending, or test not ordered) is displayed on the order form, and the MLM determines if the prescriber can place the order, place it but require an over-ride reason, or be blocked from placing the order. Since implementation, more than 725 medication orders have been placed for over 230 patients by 154 different prescribers for the three drugs included in our PG program. Prescribers commonly used an over-ride reason when placing the order mainly because patients had been receiving the drug without reaction before implementation of the CDS program. Successful incorporation of PG CDS into the NIH CC EHR required a coordinated, interdisciplinary effort to ensure smooth activation and a positive effect on patient care. Prescribers have adapted to using the CDS and have ordered PG testing as a direct result of the implementation.

Keywords: Clinical Decision Support; Computerized Prescriber Order Entry; Informatics; Patient Safety; Pharmacogenetics.

Figure 1

The clinical decision support data flow algorithm used for carbamazepine is shown. The medical logic module checks for the laboratory (lab) test first. If laboratory test results are found, a message appropriate to the results is displayed to the prescriber. If results are not found, then a different message is displayed recommending that the pharmacogenetics (PG) test is carried out. In this case, the PG Testing Implementation Committee (PGTIC) decided that an order can be placed if the gene variation is found, the test results are pending, or to proceed without ordering the test as long an over-ride reason is provided. In contrast, the PGTIC decided to block the order for abacavir if the relevant gene variation is detected.

Figure 2

The design for the order set form for drugs included in the pharmacogenetics (PG) program is shown. In this case, the information displayed to the prescriber is based on the case where the HLA test has not yet been ordered. The displayed messages and order actions are determined by the control table. The standard design for the order set form includes the following areas. (A) Message box where the clinical information message is displayed. (B) Message box where over-ride reasons are displayed, if appropriate for the case and test result. The ‘over-ride reason number’ field becomes a required entry if an over-ride reason is allowed. (C) Message box where PG test information is displayed. (D) Grid where PG tests can be ordered or are automatically preselected depending on the case. (E) Grid where medications can be ordered. CRIS, Clinical Research Information System.

Figure 3

The resulting order placed through one of the order set forms is shown. A field has been added to our standard order form that provides the over-ride reason, if appropriate, selected by the prescriber. BMI, body mass index; BSA, body surface area.