Study finds obesity linked to kidney injury after heart surgery

July 3, 2012 by Kathy Whitney

(Medical Xpress) -- Obesity increases the risk of acute kidney injury (AKI) following cardiac surgery, according to a Vanderbilt study published in the Journal of the American Society of Nephrology.

Considered common after cardiac surgery, AKI represents a fivefold increase in within 30 days after the procedure and is associated with longer hospital stays and a range of complications.

The study, led by anesthesiologist Frederic T. (Josh) Billings IV, M.D., M.Sc., followed a sample of 455 cardiac surgery patients at Vanderbilt University Hospital and Brigham and Women’s Hospital in Boston. Some 25 percent of the patients developed AKI after their procedure.

The study found that patients with a higher body mass index (BMI) had a much greater risk. After adjusting for several other risk factors, the odds of AKI increased a staggering 26.5 percent for every five-point increase in a patient’s BMI.

Billings and colleagues used a statistical technique called mediation analysis to discover that oxidative stress could be the mechanism by which influences acute . Oxidative stress is the toxic overabundance of reactive oxygen species, brought on by excess generation or insufficient elimination.

“By identification of this mechanism, we now may be able to target intraoperative oxidative stress with the hope of reducing injury following . That may be particularly appropriate for obese individuals,” Billings said.

The authors noted that the finding is “consistent with the hypothesis that oxidative partially mediates the association between BMI and AKI.”

“I think we learned something really important by doing the mediation analysis,” said biostatistician Jonathan Schildcrout, Ph.D., one of the study’s authors. “You could have just examined the BMI and AKI association, and everybody would have said, ‘OK, obese people have higher risk of AKI.’

“When you learn the mechanism, you can start to learn how to intervene to prevent the injury,” Schildcrout said.

Explore further: Patients with persistent kidney injuries rarely see specialists

More information: The study was funded by the National Institutes of Health (RO1HL77389, RO1HL65193, and UL1RR024975). Clinical Trial Registration: NCT00141778.

Related Stories

Recommended for you

Monkeys in Asia harbor virus from humans, other species

November 19, 2015

When it comes to spreading viruses, bats are thought to be among the worst. Now a new study of nearly 900 nonhuman primates in Bangladesh and Cambodia shows that macaques harbor more diverse astroviruses, which can cause ...

One-step test for hepatitis C virus infection developed

November 14, 2015

UC Irvine Health researchers have developed a cost-effective one-step test that screens, detects and confirms hepatitis C virus (HCV) infections. Dr. Ke-Qin Hu, director of hepatology services, will present findings at the ...

Computer model reveals deadly route of Ebola outbreak

November 10, 2015

Using a novel statistical model, a research team led by Columbia University's Mailman School of Public Health mapped the spread of the 2014-2015 Ebola outbreak in Sierra Leone, providing the most detailed picture to date ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.