Firefighters who arrived early or spent more time at the World Trade Center site after the 9/11 attacks seem to have a modestly higher risk of developing heart problems compared with those who came later or stayed less, doctors reported Friday.

The research might have implications for any efforts to expand the list of health problems eligible for payment from a victim compensation fund.

The study doesn’t prove that dust or anything else about the disaster caused the firefighters to experience greater heart risks. Nor does it compare the New York City firefighters to the general population or to other responders, such as paramedics or construction workers.

But it does suggest that working at the site raised heart health risks for some firefighters more than others. Those who arrived by noon on Sept. 11, 2001, had a 44% greater chance of suffering a heart problem in the years since the attack compared to firefighters who came hours or days later.


The risk was 33% higher for those who worked at Ground Zero for at least six months compared to those who spent less time at the site.

Those differences may sound large, but heart problems were fairly uncommon — only about 5% of these firefighters developed one.

“This is a modest increase, not an epidemic,” said Dr. David Prezant, chief medical officer of the New York City Fire Department and a leader of the study. However, he added, “this risk increases over time; it doesn’t disappear.”

Results of the federally funded study were published in the journal JAMA Network Open.


Prezant and his colleagues tracked the health of 9,796 male firefighters through 2017 — 16 years after the collapse of the twin towers exposed many to a cloud of thick dust and particles from fires that burned for days. Female firefighters were excluded from the analysis because there were only 25 of them and their heart risks may differ.

Medical records were available for years before the attacks, so researchers could account for factors like cholesterol levels, smoking history and blood pressure, which also influence heart health.

They documented 489 heart problems since the disaster, including 120 heart attacks and roughly 300 procedures or surgeries for clogged arteries. Risks were higher among the 1,600 firefighters who arrived at the site by noon on the day of the attack, and among the 2,400 who worked there for six months or more.

There are good records on arrival times but less documentation for the duration of time spent at the site. For instance, being counted as having worked one month could mean that a firefighter was there for one day during that month or for 30 days. As a result, the finding that risk increased for those who worked there for at least six months is less reliable, researchers said.


Judith Graber, a researcher at Rutgers School of Public Health who has studied other 9/11 responders, called the research “very well conducted” and said “the important thing is the accumulation of evidence” suggesting increased risk.

Prezant said other studies have found signs indicative of a greater risk of heart problems, which are not currently covered by the program that treats responders or the victim compensation fund. He said administrators will need more information to decide whether to include those conditions for any groups, such as firefighters who came to the site in the first few hours.

“This adds to the evidence, but it doesn’t guarantee coverage,” he said.

Dr. Nieca Goldberg, a cardiologist at NYU Langone Health and spokeswoman for the American Heart Assn., said 9/11 responders must stay alert for possible problems.


“Everyone needs to know potential symptoms of a heart attack so they can get rapid care,” she said.

Marchione writes for the Associated Press.