Featured Research

from universities, journals, and other organizations

Improved Statistical Tool To Rank Sickest Patients Waiting For Liver Transplants

Date:
September 3, 2008
Source:
Mayo Clinic
Summary:
Researchers have developed an improved statistical model that could help ensure that the sickest patients receive liver transplants first.

Mayo Clinic researchers have developed an improved statistical model that could help ensure that the sickest patients receive liver transplants first.

Researchers found that including serum sodium concentration in the statistical model now used could reduce by 7 percent the number of patients (as many as 50 people) who die each year while waiting for a liver transplant. Serum sodium levels can be measured with a blood test.

The study will be published in the Sept. 4, 2008, issue of the New England Journal of Medicine.

"The subset of patients with the lowest sodium blood levels is not served well by the current system," says W. Ray Kim, M.D., liver transplant physician at Mayo Clinic and lead researcher on the study. Low serum sodium occurs in patients with advanced liver disease, who frequently have a large amount of ascites (fluid in abdomen), a serious complication of liver cirrhosis.

In the United States, the United Network for Organ Sharing (UNOS), a nonprofit, scientific and educational organization, administers the distribution of organs from deceased donors to patients waiting for transplants.

In 2001, Mayo Clinic researchers developed the formula used to rank patients waiting for livers from deceased donors. Called the Model for End-Stage Liver Disease (MELD), it was adopted by UNOS in 2002. The highest MELD scores indicate the sickest patients, who are placed at the top of the transplant waiting list.

The MELD score is based on three standard laboratory tests:

  • Total serum bilirubin concentration, indicated by jaundice
  • International normalized ratio for the prothrombin time, which measures the blood's ability to clot
  • Serum creatinine concentration, an indicator of renal (kidney) function

"The addition of sodium to MELD would be a relatively modest improvement," says Dr. Kim. "Since low serum sodium does not affect the majority of patients, we didn't pick it up in our original work. However, we have discovered that in those affected, low sodium has a substantial impact on mortality. This impact is particularly large in patients with low MELD, who would be placed low on the waiting list under the current system."

How the study was done. In this observational study, researchers analyzed patient data collected upon UNOS registration for liver transplantation. In 2005, there were 6,769 patients placed on the list. Of those, 422 died and 1,781 underwent liver transplant within 90 days. Based on these data, researchers created a new statistical model that incorporates serum sodium and MELD.

The new model was verified by using waiting-patient data from 2006, when 477 patients died within three months of placement on the waiting list. "By factoring in sodium, researchers predicted that about 7 percent of deaths of waiting patients would have had considerably higher priority for transplant, and it may have prevented their deaths," says Dr. Kim.

More than 400 patients receive liver transplants at Mayo Clinic's sites in Minnesota, Florida and Arizona each year. Mayo Clinic is the most experienced liver transplant center in the nation, with some of the highest survival rates in the world.

Other Mayo Clinic researchers involved in this study include Walter Kremers, Ph.D.; Russell Wiesner, M.D.; Patrick Kamath, M.D.; Joanne Benson; and Terry Therneau, Ph.D.


Story Source:

The above story is based on materials provided by Mayo Clinic. Note: Materials may be edited for content and length.


Cite This Page:

Mayo Clinic. "Improved Statistical Tool To Rank Sickest Patients Waiting For Liver Transplants." ScienceDaily. ScienceDaily, 3 September 2008. <www.sciencedaily.com/releases/2008/09/080903172148.htm>.
Mayo Clinic. (2008, September 3). Improved Statistical Tool To Rank Sickest Patients Waiting For Liver Transplants. ScienceDaily. Retrieved September 23, 2014 from www.sciencedaily.com/releases/2008/09/080903172148.htm
Mayo Clinic. "Improved Statistical Tool To Rank Sickest Patients Waiting For Liver Transplants." ScienceDaily. www.sciencedaily.com/releases/2008/09/080903172148.htm (accessed September 23, 2014).

Share This



More Health & Medicine News

Tuesday, September 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Liberia Pleads for Help to Fight Ebola

Liberia Pleads for Help to Fight Ebola

AP (Sep. 22, 2014) Liberia's finance minister is urging the international community to quickly follow through on pledges of cash to battle Ebola. Bodies are piling up in the capital Monrovia as the nation awaits more help. (Sept. 22) Video provided by AP
Powered by NewsLook.com
Ebola Doctor Says Border Controls Critical

Ebola Doctor Says Border Controls Critical

AP (Sep. 22, 2014) A Florida doctor who helped fight the expanding Ebola outbreak in West Africa says the disease can be stopped, but only if nations quickly step up their response and make border control a priority. (Sept. 22) Video provided by AP
Powered by NewsLook.com
Global Ebola Aid Increasing But Critics Say It's Late

Global Ebola Aid Increasing But Critics Say It's Late

Newsy (Sep. 21, 2014) More than 100 tons of medical supplies were sent to West Africa on Saturday, but aid workers say the global response is still sluggish. Video provided by Newsy
Powered by NewsLook.com
Sierra Leone in Lockdown to Control Ebola

Sierra Leone in Lockdown to Control Ebola

AP (Sep. 21, 2014) Sierra Leone residents remained in lockdown on Saturday as part of a massive effort to confine millions of people to their homes in a bid to stem the biggest Ebola outbreak in history. (Sept. 20) 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