Study shows women less likely to survive out-of-hospital cardiac arrest than men

December 14, 2020

DALLAS - Dec. 15, 2020 - A study of patients resuscitated from out-of-hospital cardiac arrest shows that women have a lower likelihood of survival compared with men and are less likely to receive procedures commonly administered following cardiac arrest.

The multicenter study, led by UT Southwestern researchers, was published online today in Circulation. The percentage of patients who survived to hospital discharge was significantly lower among women (22.5 percent) than men (36.3 percent). About 300,000 people suffer cardiac arrests outside of a hospital setting each year in the U.S.

"Our work points to new directions in how we can work to improve survival in women," says Ahamed Idris, M.D., a professor of emergency medicine and internal medicine at UT Southwestern who practices at Parkland Memorial Hospital. "Why are emergency interventions different with women than with men?"

This study draws upon data from two clinical trials and a cardiac arrest registry conducted by the Resuscitation Outcomes Consortium (ROC), an initiative of the National Institutes of Health and the U.S. Department of Defense. The trials included patients at 10 sites in the U.S. and Canada during 2010-2015.

Among 4,875 successfully resuscitated patients in the study, 37.4 percent were women and 62.6 percent were men. The men were slightly younger, with an average age of 65 versus 67 for the women.

According to Idris, there are two treatments available for cardiac arrest following a successful resuscitation: therapeutic hypothermia (cooling a person's body to a temperature that is lower than normal) and coronary angiography, which is used to examine arteries to the heart and open them to blood flow. The study documents that women receive hypothermia 35 percent of the time compared with 44 percent for men. With coronary angiography, women receive this treatment 14 percent of the time compared with 30 percent for men. Further study is needed to find out why this disparity exists.

Also, women were 6 percent less likely to receive cardiopulmonary resuscitation (CPR) from a bystander. Other data showed fewer of them had cardiac arrests that were witnessed or had shockable rhythm versus the men.

Idris says that men are more likely to suffer cardiac arrest in public, resulting in a quicker call to 911 from a companion or bystander and therefore doubling their chance of survival to hospital discharge. However, once resuscitated, both women and men begin recovery from similar starting points.

"This is one of few studies looking at what happens to people post-resuscitation," says cardiologist Ambarish Pandey, M.D., assistant professor of internal medicine at UTSW. "Now we need insight into whether these outcomes may be driven by what happens in the hospital. We have a long way to go in providing gender equity in treatment."

Dallas-Fort Worth was the largest U.S. site in the ROC, with 36 hospitals and 22 emergency medicine agencies involved across Dallas, Collin, and Tarrant counties, including both UT Southwestern and Parkland Memorial Hospital. While the original Resuscitation Outcomes Consortium was discontinued in 2016, the Dallas-Fort Worth branch, the Center for Resuscitation Research, continues to be maintained with studies ongoing by Idris, who is director of emergency medicine research in the department of emergency medicine at UT Southwestern.

"Were the women sicker or was there a difference in care?" asks Purav Mody, M.D., a cardiologist and assistant professor of internal medicine at UT Southwestern. "Our study demonstrates the existence of gender disparities in post-resuscitation care and highlights the need for future research focused on decision-making and care being provided in the post-resuscitation phase in order to narrow gender-based differences in cardiac arrest outcomes."

Idris was part of the team that launched the study 15 years ago. "We followed these patients into the hospital and tracked what they received: every chest compression, every shock treatment, every ventilation (forcing air into the patient's lungs to start the breathing process). We studied the CPR features used out-of-hospital to see which worked best."

When he first started working in emergency medicine in 1979, heart attack patients usually were placed in intensive care for observation. If the patient went into cardiac arrest, the person was given shock treatment. Treatment options today, such as aspirin, beta blockers, or anti-coagulants, were not available at the time. Similarly, for patients resuscitated from cardiac arrest, once they reach the hospital they can receive therapeutic hypothermia and coronary angiography, both of which improve outcomes, but were not available in 1979.

"Today, if a patient makes it to the hospital early enough, they should not walk away with permanent heart damage," Idris says.
-end-
Co-senior author on the study is Laurie Morrison, M.D., University of Toronto, Canada. Other researchers involved include Arthur S. Slutsky, Matthew W. Segar, Alex Kiss, Paul Dorian, Janet Parsons, Damon C. Scales, Valeria E. Rac, Sheldon Cheskes, Arlene S. Bierman, Beth L. Abramson, Sara Gray, Rob A. Fowler, and Katie N. Dainty.

About UT Southwestern Medical Center

UT Southwestern, one of the premier academic medical centers in the nation, integrates pioneering biomedical research with exceptional clinical care and education. The institution's faculty has received six Nobel Prizes, and includes 23 members of the National Academy of Sciences, 17 members of the National Academy of Medicine, and 13 Howard Hughes Medical Institute Investigators. The full-time faculty of more than 2,500 is responsible for groundbreaking medical advances and is committed to translating science-driven research quickly to new clinical treatments. UT Southwestern physicians provide care in about 80 specialties to more than 105,000 hospitalized patients, nearly 370,000 emergency room cases, and oversee approximately 3 million outpatient visits a year.

UT Southwestern Medical Center

Related Cardiac Arrest Articles from Brightsurf:

Outcomes for out-of-hospital cardiac arrest during COVID-19 pandemic
This study used a large US registry of out-of-hospital cardiac arrests to asses the association between the COVID-19 pandemic and the outcomes of out-of-hospital cardiac arrests, including in areas with low and moderate COVID-19 disease.

Cardiac arrest is common in critically ill patients with COVID-19
Cardiac arrest is common in critically ill patients with covid-19 and is associated with poor survival, particularly among patients aged 80 or older, finds a study published by The BMJ today.

In-hospital cardiac arrest in COVID-19
Outcomes of in-hospital cardiac arrest among patients with COVID-19 are examined in this case series.

New risk tool developed for cardiac arrest patients
Experts have developed a risk score to predict cardiac arrest patient outcomes.

Intravenous sodium nitrite ineffective for out-of-hospital cardiac arrest
Among patients who had an out-of-hospital cardiac arrest, intravenous sodium nitrite given by paramedics during resuscitation did not significantly improve their chances of being admitted to or discharged from the hospital alive, according to research presented at the American College of Cardiology's Annual Scientific Session Together with World Congress of Cardiology (ACC.20/WCC).

Getting to the heart of epinephrine use in pediatric cardiac arrest patients
The effectiveness of epinephrine treatment during resuscitation of adult patients with cardiac arrest is generally promising, but little is known about its effects in pediatric patients.

Bystanders can help more cardiac arrest victims survive
Only 8% of Americans survive cardiac arrest outside a hospital, but that percentage could increase significantly if bystanders recognize cardiac arrest and perform simple lifesaving tasks, a UVA Health physician says in a New England Journal of Medicine article.

Opioid-related cardiac arrest patients differ from other cardiac arrests
People who suffer cardiac arrest due to an opioid overdose are younger, have fewer chronic medical conditions and may be more likely to be to receive bystander CPR, according to a review of emergency response records in Maine.

Selective coronary angiography following cardiac arrest
In the current issue of Cardiovascular Innovations and Applications volume 4, issue 2, pp.

Sudden cardiac arrest in athletes: Prevention and management
It's marathon season, and every so often a news report will focus on an athlete who has collapsed from sudden cardiac arrest.

Read More: Cardiac Arrest News and Cardiac Arrest Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.