Featured Research

from universities, journals, and other organizations

Transfusions add risk in some heart attacks, finds study of patients with anemia

Date:
December 26, 2012
Source:
Brown University
Summary:
A new study finds that while blood transfusions for heart attack patients with anemia are commonly performed in emergency rooms, the practice can increase the risk of death when the transfusions are too extensive. The authors, led by Saurav Chatterjee, a cardiology fellow at Brown University, compared evidence from 10 prior studies of more than 203,000 patients.

When heart attack patients present in the emergency department with some degree of anemia, or anemic patients have a heart attack, physicians have a tendency, but not much guidance, about whether to provide a blood transfusion. The idea is that a transfusion could help more oxygen get to the heart. Recent national guidelines suggested that there simply isn't good evidence to encourage or discourage the common practice, but a new meta-analysis of 10 studies involving more than 203,000 such patients comes down on the side of it increasing the risk of death.

Related Articles


The next step for determining when the practice could be appropriate needs rigorous randomized trials that will generate more decisive, high-quality data, said lead author Dr. Saurav Chatterjee, a cardiology fellow at the Alpert Medical School of Brown University and the Providence VA Medical Center.

For the analysis published Dec. 24 in the Archives of Internal Medicine, Chatterjee and his co-authors combined and analyzed data from studies in which anemia patients with heart attacks either received "liberal" transfusions or received more restricted versions of the treatment or no transfusions at all. Liberal transfusions were defined as cases in which patients either received two units of blood or more or had a transfusion even with a hematocrit reading (a measure of red blood cell concentration) higher than 30 percent (normal is in the low 40s).

What the researchers found, after statistical adjustments to control for important medical factors, was that the risk of death was 12 percent higher for people who received the liberal transfusions than those who did not. Moreover, the group that received liberal transfusions had twice the odds of having another heart attack.

"What we found is that the possibility of real harm exists with transfusion," Chatterjee said. "It is practiced in emergency departments all across the United States. I think it is high time that we need to answer the question definitively with a randomized trial."

Of the 10 papers that Chatterjee and his co-authors reviewed, all but one were observational studies. The only randomized trial was a small pilot experiment.

Searching for an answer

Chatterjee began the study when he was a resident at Maimonides Medical Center in New York. He noticed a paper by the AABB (formerly the American Association of Blood Banks) in which the association said there was not enough clinical evidence for or against transfusions in heart attack patients.

For clinicians, the practice has always been a tough judgment call. Some transfusions are clearly necessary, for example when a patient's troubles include not just a heart attack but also severe ongoing bleeding, Chatterjee said. But transfusions also create health risks, such as an increase in potential clotting because platelets may clump together more, or from an inflammatory immune response to the introduction of blood of a "foreign" source into the body.

Chatterjee and his co-authors decided to comb the literature to determine whether, if properly combined and analyzed, existing data could provide some insight. They found 729 potentially relevant studies, but only 10 that had the right data to help answer the question.

Few as they were, Chatterjee said, the studies all told much the same story.

"One of the things that struck us is that there were very few studies in evidence of transfusion at all," Chatterjee said. "In our case, though, we found that the effect was pretty consistently harmful across the spectrum of studies, spectrum of time, and spectrum of patients that were enrolled in the individual studies."

Chatterjee said the study should not be taken to mean that transfusions should be stopped altogether for anemic heart attack patients. Instead, he said, doctors must continue exercising their clinical judgment, at least until results from a large, well-designed randomized trial can be produced. Mindful of the risk his study found, however, they might just want to shift their thinking about where the border is among borderline cases.

"Before a definitive trial is out there, we should be conservative, especially considering the high risk of harm," he said.

In addition to Chatterjee, the paper's other authors are Jorn Wetterslev of the Centre for Clinical Intervention Research in Copenhagen, Denmark; Abhishek Sharma and Edgar Lichstein of Maimonedes Medical Center; and Debabrata Mukherjee of Texas Tech University.


Story Source:

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


Journal Reference:

  1. Chatterjee S, Wetterslev J, Sharma A, Lichstein E, Mukherjee D. Association of Blood Transfusion With Increased Mortality in Myocardial Infarction: A Meta-analysis and Diversity-Adjusted Study Sequential Analysis. Archives of Internal Medicine, 2012; DOI: 10.1001/2013.jamainternmed.1001

Cite This Page:

Brown University. "Transfusions add risk in some heart attacks, finds study of patients with anemia." ScienceDaily. ScienceDaily, 26 December 2012. <www.sciencedaily.com/releases/2012/12/121226080904.htm>.
Brown University. (2012, December 26). Transfusions add risk in some heart attacks, finds study of patients with anemia. ScienceDaily. Retrieved December 22, 2014 from www.sciencedaily.com/releases/2012/12/121226080904.htm
Brown University. "Transfusions add risk in some heart attacks, finds study of patients with anemia." ScienceDaily. www.sciencedaily.com/releases/2012/12/121226080904.htm (accessed December 22, 2014).

Share This


More From ScienceDaily



More Health & Medicine News

Monday, December 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Christmas Kissing Good for Health

Christmas Kissing Good for Health

Reuters - Innovations Video Online (Dec. 22, 2014) Scientists in Amsterdam say couples transfer tens of millions of microbes when they kiss, encouraging healthy exposure to bacteria. Suzannah Butcher reports. Video provided by Reuters
Powered by NewsLook.com
Brain-Dwelling Tapeworm Reveals Genetic Secrets

Brain-Dwelling Tapeworm Reveals Genetic Secrets

Reuters - Innovations Video Online (Dec. 22, 2014) Cambridge scientists have unravelled the genetic code of a rare tapeworm that lived inside a patient's brain for at least four year. Researchers hope it will present new opportunities to diagnose and treat this invasive parasite. Matthew Stock reports. Video provided by Reuters
Powered by NewsLook.com
Touch-Free Smart Phone Empowers Mobility-Impaired

Touch-Free Smart Phone Empowers Mobility-Impaired

Reuters - Innovations Video Online (Dec. 21, 2014) A touch-free phone developed in Israel enables the mobility-impaired to operate smart phones with just a movement of the head. Suzannah Butcher reports. Video provided by Reuters
Powered by NewsLook.com
Earthworms Provide Cancer-Fighting Bacteria

Earthworms Provide Cancer-Fighting Bacteria

Reuters - Innovations Video Online (Dec. 21, 2014) Polish scientists isolate bacteria from earthworm intestines which they say may be used in antibiotics and cancer treatments. Suzannah Butcher reports. Video provided by Reuters
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