Precision Medicine Finds A Home In Primary Care
By Joel Diamond, MD, FAAFP, an Adjunct Associate Professor of Biomedical Informatics at the University of Pittsburgh. He is a diplomat of the American Board of Family Practice and a fellow in the American Academy of Family Physicians. He cares for patients at Handelsman Family Practice in Pittsburgh and serves as chief medical officer for 2bPrecise.
In its earliest days, genetic and genomic testing typically fell under the purview of select specialties such as oncology, rare diseases and maternal-fetal medicine, but no longer. Increasingly, and appropriately, precision medicine is likewise finding a home within primary care.
It makes sense. The primary care provider (PCP) typically is the first-line point of access for a wide variety of medical services. Advances in genetic and genomic science equip PCPs with insights to speed accurate diagnosis of complex presenting conditions, improve medication safety for treatment of common conditions, and identify treatments and care plans most likely to produce desired outcomes.
Consider the value precision medicine can deliver in these three areas alone:
Improved medication safety. Healthcare has become adept at managing drug allergies, but lags in other areas that likewise influence medication safety and efficacy. Genetic variations drive how well – or poorly – a patient metabolizes a specific drug. If an individual is a fast metabolizer of clopidogrel, for example, his or her body will process it too quickly.
The medication may not provide appropriate protection against clotting which, in turn, has life-threatening consequences. Pharmacogenomic (PGx) testing provides PCPs with the information they need to select the safest, most effective medications for each patient. PGx is particularly valuable for PCPs treating behavioral health issues such as anxiety or depression (typical “trial-and-error” approaches delay therapeutic benefit for months), pain management (where efficacy is critical to timely recovery, management of comorbidities like high blood pressure and addiction avoidance) and common cardiovascular conditions like hyperlipidemia.
Better treatment decisions. Understanding a patient’s molecular profile, obtained through germline testing, enables PCPs to better understand the role genetics/genomics plays so they can arrive at a more precise diagnosis and therefore optimal treatment. PCPs treat many patients with congestive heart failure, for instance.
A stratification of this population through genomic testing may result in vastly different protocols. Recognizing patients with inherited dilated cardiomyopathy is, therefore, very important – not only for making the best treatment decision for them, but also enabling communication about risk to other family members. A second example could involve a patient with familial hypercholesterolemia, also revealed through germline testing and likewise requiring a care plan that differs from treatment of non-genetic forms of the condition.
Reduced costs. Results from genetic/genomic testing represent nothing more – and nothing less – than an additional data set for PCPs to use when caring for patients. In many cases, that information helps the provider “short circuit” a standard diagnostic process.
It is not uncommon for patients to schedule an appointment with their PCP due to heart palpitations and syncope. Initial workup – preceding any referral to a cardiologist or neurologist – might include 24-hour Holter monitoring, echocardiography and lab tests.
If the patient’s history includes family members dying suddenly of arrythmia or cardiomyopathy, the PCP might also decide to order a genetic test. Results, along with a referral to an electrophysiologist, would enable providers to bypass further expensive and time-consuming tests (e.g., MRI, carotid doppler studies, tilt table).
It is clear that precision medicine adds significant value to primary care. For PCPs to fully leverage this value, however, they must be able to access the information and apply it as they are making clinical decisions.
As noted above, genetic/genomic test results represent a new data set – and that means practices need informatics tools so the insights can be managed and shared with members of the care team. It is critical that practice leadership begin the process of educating PCPs about the benefits that can be derived through precision medicine, as well as implement the technology infrastructure essential for delivering test results within the clinical workflow.