Do you know every prescription and over-the-counter medication your patient is taking? The Medicare Annual Wellness Visit requires you to review a list of all their medications from all their providers.
A recent poll by the John A. Hartford Foundation found that 33 percent of patients did not have a regular review of their medications.
Medication errors occur in nearly one out of every five doses given to patients. ADRs cause more than 100,000 deaths a year, one of the top five causes of death. If eliminated, ADRs could save the United States $2 billion a year.
Seniors who are eligible for the free AWV take the most medications and therefore are at the most risk for an ADR. For example, interactions among prescribed medications result in more than 50 percent of emergency department visits by seniors (Budnitz et al, 2007) and one in four seniors receive a medication they should not have been prescribed (Aparusa & Mort, 2004; Salazar et al 2007).
Seniors often see more than one provider and take OTC medications they hear about from the media and friends. Medication reconciliation from a basic drug-to-drug interaction analysis can be provided by most EHRs and pharmacists, but only when they know all the medications a patient is taking.
More complete analysis is provided by the newest science known as “personalized medication prescribing or personalized medicine” which uses pharmacogenomics and pharmacogenetic testing.
The patient’s DNA is analyzed to determine the patient drug metabolizing gene variants. The most studied enzymes are the members of the Cytochrome P450 family of about 50 liver enzymes. They account for about 75 percent of the total number of different metabolic reactions, such as the 2C19 effect on Plavix (clopidogrel). The FDA is so committed to using genetic information to better tailor therapeutic dosing that it has required a “black box warning” on Plavix that says mutations in a patient’s genetic profile may render them unable to respond to the drug and places them at increased risk for heart attack and stroke. They list over 100 other drugs and combinations on their site which could indicate ineffective treatment due to genetic profiles.
The AMA has been developing resources that aim to enhance physicians’ understanding of pharmacogenomics. Among those are a CME course on pharmacogenetics, plus a brochure on the genetic variation that influences warfarin dosing.
The most effective analysis of medication interaction is to analyze not only the drug-to-drug interaction, but also the drug-to-DNA interaction. More effective still is to conduct cumulative interaction testing on the effect of each drug as a combination with the genetic profile.
Patients can be separated into genetic classes of poor, intermediate, normal, and ultra-rapid metabolizers of drugs based on their enzyme variations. When a patient who is a poor metabolizer of a particular drug, like a patient with a poor CYP2C19 taking Plavix, he/she will process the drug more slowly or not at all, resulting in increased levels of the drug in his bloodstream and the potential for side effects and toxicity. For an ultra-metabolizer, the standard dose may be ineffective as the drug is processed too rapidly to have its full effect.
Genelex Corporation , a CLIA certified genetic lab in Seattle, has a thorough software program to provide pharmacogenetic analysis, including cumulative testing, which is covered by Medicare. They provide testing supplies direct to the physician and assume the full cost by charging insurance and Medicare.
“Eventually, everyone will have his or her own drug profile” says Frank Giardiello, MD, professor and Chief of Gastroenterology at Johns Hopkins.
Editor’s Note: The author is a paid representative for Genelex in the state of Florida.
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