A new paradigm in coagulation testing

A new paradigm in coagulation testing

The bottom line is that I am both worried and excited about the change in coagulation testing I see on the horizon. I’m not sure if my colleagues are aware of it or not, but it is there. Do I sound ominous? Well for laboratory medicine there is a significant change coming, a new paradigm in coagulation testing and since it will affect my job, I am taking notice of it. But at the same time as a healthcare provider I am excited and happy about the positive changes it will make for patients.
What is this change I see coming? Simply put, the demise of the warfarin industry. The value of this industry is in the billions, and some of those funds go to the lab. If the warfarin industry becomes obsolete, so does a source of income for labs.
First of all, a brief history lesson about warfarin. At the beginning of the 1900’s, farmers in the Midwest were noticing that their cattle were starting to die after eating in certain fields. Autopsies revealed they had all died of massive internal bleeding. The culprit was discovered to be the sweet clover they had eaten. Research isolated the compound that caused the bleeding, and it was named Coumadin. Coumadin’s action was found to decrease the blood’s clotting ability. It did this by interfering with Vitamin K’s ability to produce clotting proteins in the liver. Without being able to clot, eventually the smallest bump or scrape will lead to a massive bleed and eventually death. That is what made Coumadin such an effective poison, so effective that it was first marketed as a rat poison.
Now the major cause of death in the industrialized world is either heart attacks, strokes or both. What happens is that blood is clotting too much. A clot forms in the artery of either the brain or heart, blocking blood circulation. So if the clotting can be prevented, the blood flow is unaffected and death and sickness are prevented. Since Coumadin prevents blood from clotting, it can be used as a medication to prevent heart attacks and strokes. It seemed to work and was renamed Warfarin. These types of medication are known as anticoagulants (anti-against, coagulants-clotting).
Unfortunately, just because it was renamed Warfarin and used as a medicine didn’t mean that it wasn’t still poisonous. Warfarin levels had to be monitored by a lab test called the INR. If the INR was at an acceptable level then the medication didn’t have to be adjusted. Unfortunately, sometimes the INR would become unstable and the patient would have to have multiple blood tests to find the right dosage to bring the INR back to a therapeutic level. Remember, this stuff was originally rat poison, and if the INR was too high, the patient could bleed to death. Sometimes the patient will require a blood transfusion to replace the clotting factors they are missing.
Of course, this is all a major source of work (and revenue) for the lab. It is not convenient for the patients who have to have their blood constantly tested, or the physician to try and get the right dosage without killing their patient.
It has long been the Holy Grail of pharmacological research to find an anticoagulant that did not require blood testing to monitor it, nor have the nasty side effects of warfarin.
That Holy Grail has been found, and it is called Dabigatran. Next week’s entry will deal with its impact on the medical lab industry.