Featured Research

from universities, journals, and other organizations

Genetics Determine Optimal Drug Dose Of Common Anticoagulant

Date:
August 24, 2007
Source:
American Society of Hematology
Summary:
Genetic testing can be used to help personalize the therapeutic dosage of warfarin, a commonly-used anticoagulant, according to new research. This result represents one of the first applications of using an individual's genetic information to guide personal medical care.

Genetic testing can be used to help personalize the therapeutic dosage of warfarin, a commonly-used anticoagulant, according to research published in the September 1, 2007, issue of Blood, the journal of the American Society of Hematology. This result represents one of the first applications of using an individual's genetic information to guide personal medical care.

Related Articles


Because individuals metabolize drugs differently, varying doses of warfarin are needed for the drug to be effective in each patient. Too much warfarin can cause severe bleeding, and too little can cause dangerous blood clots. Currently, there is little guidance for predicting how much of the drug a person will need. Physicians have had to roughly estimate an initial dose of warfarin and then continually monitor a patient's International Normalized Ratio (INR) value (a measure of how fast the blood clots), during treatment to tweak the dosage by trial and error.

For the first time, a group of St. Louis researchers combined the standard INR method with genetic testing to predict the therapeutic warfarin dose. Since warfarin is often prescribed after major orthopedic surgery to prevent blood clots in the legs, the study followed 92 adults undergoing either total hip or knee replacement at the Washington University Medical Center, who had never previously taken the anticoagulant.

Prior to warfarin treatment, the researchers collected blood samples and each patient's medical history. The blood tests were used to examine variations in two genes, CYP2C9 and VKORC1, that may affect warfarin dosing. Variants in CYP2C9 impair the body's breakdown of warfarin; variants in VKORC1 cause increased warfarin sensitivity. The patients were assigned initial doses of warfarin based on clinical factors and their genotype. The researchers followed the patients until successful treatment outcomes were achieved several weeks later.

By combining variants in these genes with initial INR response and other clinical factors, the researchers derived a dosing equation that estimated the therapeutic warfarin dose. The researchers found that these two genes were important in predicting the response to warfarin. Additional factors, such as blood loss during surgery and smoking status, also correlated with therapeutic dose.

Using these data, the researchers developed a therapeutic model that could be used by physicians to refine warfarin dosage with greater accuracy than clinical factors alone. The researchers have made this dosing model publicly available on a free Web site, http://www.warfarindosing.org, and are now validating it in orthopedic and non-orthopedic patients beginning warfarin therapy.

If validated, particularly in patients taking warfarin for reasons other than orthopedic surgery, such as to prevent stroke, this gene-based dosing could predict a safe and effective warfarin dose at the start of treatment, thus minimizing the risks of the current trial-and-error approach.

This work was funded by the National Institutes of Health.


Story Source:

The above story is based on materials provided by American Society of Hematology. Note: Materials may be edited for content and length.


Cite This Page:

American Society of Hematology. "Genetics Determine Optimal Drug Dose Of Common Anticoagulant." ScienceDaily. ScienceDaily, 24 August 2007. <www.sciencedaily.com/releases/2007/08/070821112246.htm>.
American Society of Hematology. (2007, August 24). Genetics Determine Optimal Drug Dose Of Common Anticoagulant. ScienceDaily. Retrieved December 19, 2014 from www.sciencedaily.com/releases/2007/08/070821112246.htm
American Society of Hematology. "Genetics Determine Optimal Drug Dose Of Common Anticoagulant." ScienceDaily. www.sciencedaily.com/releases/2007/08/070821112246.htm (accessed December 19, 2014).

Share This


More From ScienceDaily



More Health & Medicine News

Friday, December 19, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

The Best Tips to Curb Holiday Carbs

The Best Tips to Curb Holiday Carbs

Buzz60 (Dec. 19, 2014) It's hard to resist those delicious but fattening carbs we all crave during the winter months, but there are some ways to stay satisfied without consuming the extra calories. Vanessa Freeman (@VanessaFreeTV) has the details. Video provided by Buzz60
Powered by NewsLook.com
Sierra Leone Bikers Spread the Message to Fight Ebola

Sierra Leone Bikers Spread the Message to Fight Ebola

AFP (Dec. 19, 2014) More than 100 motorcyclists hit the road to spread awareness messages about Ebola. Nearly 7,000 people have now died from the virus, almost all of them in west Africa, according to the World Health Organization. Video provided by AFP
Powered by NewsLook.com
Researchers Test Colombian Village With High Alzheimer's Rates

Researchers Test Colombian Village With High Alzheimer's Rates

AFP (Dec. 19, 2014) In Yarumal, a village in N. Colombia, Alzheimer's has ravaged a disproportionately large number of families. A genetic "curse" that may pave the way for research on how to treat the disease that claims a new victim every four seconds. Duration: 02:42 Video provided by AFP
Powered by NewsLook.com
Kids Die While Under Protective Services

Kids Die While Under Protective Services

AP (Dec. 18, 2014) As part of a six-month investigation of child maltreatment deaths, the AP found that hundreds of deaths from horrific abuse and neglect could have been prevented. AP's Haven Daley reports. (Dec. 18) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins