Most frequent cause of death among firefighters is not flames, it's their hearts

Dec 18 2008

Forty-four percent of U.S. firefighters who died on duty in 2007 succumbed to a heart attack, based on data from the U.S. Fire Administration. That figure is twice the number of cardiovascular deaths among on-duty police officers.

Despite the high incidence of death among these important protectors of society, no recording of the electrical activity of the heart over time using an electrocardiogram (ECG) has been collected to determine why firefighters are at unusually high risk of dying on the job.

Mary Carey, Ph.D., assistant professor in the University at Buffalo School of Nursing, has received a $411,539 two-year grant from the National Institute of Nursing Research to monitor firefighters' heart function while on duty to identify those at risk for heart attack and sudden cardiac death.

The new study, called SAFFE -- Surveying & Assessing Firefighter Fitness and Electrocardiograms -- is underway and involves 118 members of the Buffalo Fire Department in up to 12 fire precincts around the city.

A heart attack is caused by an interruption of blood flow, while sudden cardiac death results from a disruption of heart rhythm. Carey has done research on sudden cardiac death with John M. Canty Jr., M.D., Albert and Elizabeth Rekate Professor and director of the Center for Research in Cardiovascular Medicine in the UB School of Medicine and Biomedical Sciences.

"This novel study will develop a non-invasive risk stratification approach to identify more accurately which firefighters are at risk for cardiovascular events," said Carey.

"Over the longer term, this research should help develop algorithmic guidelines that would send at-risk firefighters for aggressive cardiac care to reduce their cardiovascular risk factors."

Carey's pilot study conducted with 28 Buffalo firefighters showed that they could wear a portable ECG, a device that monitors heart function beat-to-beat, while on the job, and that the device provided accurate data.

In the new study researchers first will collect firefighters' resting ECG and oxygen intake (VO2) and maximum ECG and VO2 while participants exercise on treadmill. ECG measures will continue to be collected for eight hours after returning from a call, because research shows firefighters are at highest risk of cardiac events after a call.

Participants will wear the ECG strapped to their torso, which will collect data from 10 points, called leads, continuously for 24 hours during all activities: fire and medical calls, training, meals, exercise and nonemergency duties such as maintenance, parades, classroom activities, and rest or sleep.

The relationship between heart rate and VO2 will be collected during short periods while firefighters are on duty.

"Because cardiac events are one of the leading causes of death among these first-responders who serve the public, we hope that using these measurements will help identify those whose health is at risk while they protect ours," said Carey.

James A Fallavollita, M.D., UB professor of medicine and senior scientist in the cardiovascular research center, also is a significant contributor on the study.

The University at Buffalo is a premier research-intensive public university, a flagship institution in the State University of New York system and its largest and most comprehensive campus. UB's more than 28,000 students pursue their academic interests through more than 300 undergraduate, graduate and professional degree programs. Founded in 1846, the University at Buffalo is a member of the Association of American Universities.