Cardiac arrest is a leading cause of death in the U.S. but gets just a fraction of the government’s funding for medical research, according to a new study.

Researchers aren’t sure exactly why there’s such a disparity in funding from the National Institutes of Health, but say more is definitely needed considering about 450,000 Americans die each year from cardiac arrest. Most cardiac arrest victims don’t survive.

The new analysis of funding from 2007 to 2016 is the first to evaluate the annual trend of NIH cardiac arrest research funding over time, researchers said. The analysis was published Wednesday in the Journal of the American Heart Association.

The American Heart Association’s 2017 Statistical Update does not rank cardiac arrest as a separate cause of death, but the study authors cite Institute of Medicine statistics suggesting cardiac arrest is the country’s third-leading cause of death.

NIH funds allocated for cardiac arrest have declined from $35.4 million to $28.5 million during the past decade, the researchers noted. To put the investment disparity in perspective, researchers examined figures from 2015 and found the NIH invested about $2,200 per each stroke death annually; $2,100 for each heart disease death; and $91 for each cardiac arrest death. The investment also lagged far behind diabetes ($13,000) and cancer ($9,000).

This limited government funding is especially difficult because, unlike other diseases, cardiac arrest generally doesn’t get funding from industry, including pharmaceutical manufacturers, said study author Robert Neumar, M.D., Ph.D., professor and chair of the University of Michigan Health System’s Department of Emergency Medicine.

Kelly Sawyer, M.D., M.S., knows firsthand the importance of cardiac arrest research.

Six years ago, as she was conducting cardiac arrest-related research, Sawyer went into cardiac arrest and collapsed. Because of the quick actions of her colleagues, Sawyer is alive and well today.

“A lot of my care was in the hospital,” she said. “So, I experienced some of the same treatment I was doing research on at the time. Terribly ironic.”

About 25 percent of people survive cardiac arrests in the hospital, while just over 10 percent survive outside the hospital, according to AHA statistics.

“I wasn’t out on the street like many others are,” she said. “Lay rescuers either do or do not respond, and there’s a lot of research into understanding why that is and how we can get more people to respond, so we can provide CPR more quickly.

“In the emergency department we see that often, where we know there are large delays. And we can’t necessarily make up for those large delays with our current interventions.”

While there is a shortage of NIH funding, it does indeed help, said study author Ryan A. Coute, a medical student at Kansas City University of Medicine and Biosciences who conducted the research while completing a Sarnoff fellowship at University of Michigan.

“Research can lead to new resuscitation treatment strategies, innovative ways to identify people at risk for cardiac arrest and methods to optimize post-cardiac arrest care, to name a few,” he said.

For example, NIH funding of the Resuscitation Outcomes Consortium led to overall survival increases from 10.2 to 12.4 percent from 2006 to 2015 at participating study sites. The NIH-funded Public Access Defibrillation Trial demonstrated that deployment of public access defibrillators saves lives. And multiple animal studies funded by NIH have demonstrated hypothermia reduces brain injury caused by cardiac arrest, according to Coute.

What the new study doesn’t specify is why NIH research funds for cardiac arrest are dwindling.

“Our results show a lack of growth in the number of investigators funded by NIH to perform cardiac arrest research, which may suggest an inadequate pool of investigators focused on this disease,” Coute said. “We should encourage physician-scientists from various fields of medicine, such as cardiology, neurology and critical care, to focus their talents on cardiac arrest research.”

The problem is both a lack of researchers and funds, Neumar said.

Research dollars, according to Neumar, are needed to optimize the system of cardiac arrest care, so that bystanders, emergency medical services and hospital providers can work together and quickly to save lives.

“The other important area is post-cardiac arrest care,” Neumar said. “Once someone is resuscitated and gets to the hospital, that’s really only half the battle. Keeping them alive and minimizing the brain damage caused by cardiac arrest are areas where important research is needed.”