There is a wealth of published information describing interactions between drugs used to treat cardiovascular disease and the genetic variations that can affect how patients respond to them. But few heart specialists make routine use of this potentially life-saving data.
To help physicians make better-informed clinical decisions, researchers from the University of Chicago and Stanford University combed through scientific literature on the pharmacogenomics of 71 leading cardiovascular drugs.
“Tens of thousands of patients have been studied and the connections between common medications and the genetic variants that can lead to adverse drug reactions or treatment non-response have been described, but few physicians track this information or even know where to find it,” said study author Peter H. O’Donnell, MD, assistant professor of medicine at the University of Chicago.
“One dose does not fit all,” he said. “So we set out to boost awareness and simplify access.”
In the United States more than 50,000 patients are treated in emergency rooms annually for bad reactions to cardiovascular drugs. Patients over age 65 are particularly at risk, especially those taking warfarin and anti-platelet agents.
The researchers probed every paper published in English between January 2011 and May 2013, searching for articles that described a link between genetic variations and an unanticipated pharmacological or clinical outcome caused by a cardiovascular drug.
Creating new guidelines
They found 597 unique publications, involving 611 genetic markers or “variants” and 884 drug-variant pairs. Fifty-one of the 71 cardiovascular drugs they focused on (71.8 percent) had detectable pharmacogenomic effects.
Four high-scoring drug-variant pairs — involving the drugs clopidogrel (Plavix®), metoprolol (Lopressor®), simvastatin (Zocor®) and warfarin (Coumadin® and others) — deserved particular attention. The researchers also devoted extra attention to the nine most common cardiovascular drugs — such as simvastatin. They found that the seven most frequently prescribed medications warranted pharmacogenomic guidelines for clinical consideration.
The problem is that there is currently no one place where all this information is readily available to doctors.
“There is substantial pharmacogenetic information on cardiovascular drugs that could potentially be applied to patient care,” O’Donnell and colleagues conclude. “Considering the hundreds of millions of annual cardiovascular drug prescriptions, the frequency of adverse drug reactions, and the variable levels of drug response, the impact of this knowledge is potentially prodigious.”
myDNA medical director, Associate Professor Les Sheffield, said: “Pharmacogenomics can be informative in the area of cardiology and its use in this area is increasing. Any patient who has had a myDNA test can access their results through our secure online portal and share their test report and expert interpretation with all of their healthcare professionals, making this valuable information much more accessible.”