Ground zero workers from the Sept. 11 terrorist attacks have suffered from many health problems. Now rheumatoid arthritis and similar conditions have been added to their list of potential woes.

It is well-documented that workers who responded to the Sept. 11 terrorist attacks face increased health risks, including various forms of cancer, respiratory illness, and mental health problems.

But now, autoimmune conditions like rheumatoid arthritis (RA) have been added to their list of worries.

A recent study in the journal Arthritis and Rheumatology suggests that prolonged exposure to the ground zero work site in New York City could contribute to the development of systemic autoimmune diseases such as rheumatoid arthritis. Those ailments often have environmental triggers along with genetic components that play a factor in their development.

While RA was the most common diagnosis among the 9/11 responders who were involved in the study, it was not the only one. Other inflammatory and rheumatic conditions were prevalent, including lupus, Sjögren’s syndrome, sarcoidosis, spondyloarthritis, myositis, systemic sclerosis, antiphospholipid syndrome, and Wegener’s granulomatosis.

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More than 55,000 rescuers and responders associated with ground zero have registered as part of the World Trade Center Health Registry. Several initiatives and organizations have been formed to track the acute and long-term health issues that 9/11 workers face.

There have been reports of at least 2,500 first responders developing cancer. Ground zero workers are considered to have a 15 percent higher risk of developing cancer than the average population.

The thought is that exposure to chemicals, debris, asbestos, and dust at the 9/11 site could contribute to cancer, respiratory illness, and other health concerns that now include RA.

Researchers who uncovered the ground zero/RA link studied 16,000 people. They determined that those workers who spent at least two months at ground zero were twice as likely to develop rheumatoid arthritis than people not involved with 9/11 work. Researchers also suggested that for each month spent cleaning up ground zero, a person’s risk jumped nearly 13 percent.

Of all of the autoimmune illnesses that researchers have linked with ground zero, RA was the most prevalent, affecting 37 percent of those being studied. This fact could breathe new life into the idea that autoimmunity has an environmental component.

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According to a press release about the study, the finding of an increased risk for RA was not expected and “highlights the need for increased clinician awareness of the possibility of these and perhaps other autoimmune disorders in their WTC-exposed male patients.”

Men, in general, are often under-diagnosed with autoimmune diseases like RA because these types of illnesses often affect women more. In fact, about 75 percent of patients with RA are usually women. Many of the 9/11 workers, however, are men.

One unanswered question is whether these male workers were predisposed to these ailments.

“We know that the development of autoimmune disease occurs when an individual with a genetic predisposition comes in contact with some environmental factor that results in the person’s immune system fighting themselves,” said Dr. David Borenstein, clinical professor of medicine at George Washington University Medical Center in Washington, D.C.

It appears that working at the World Trade Center site increased this risk that was perhaps already present. Borenstein cautions, however, that not everyone who worked at the site is at risk for prolonged health issues.

“A short exposure was not enough,” he said.

It is also known that folks who were involved with 9/11 rescue and cleanup efforts have suffered mental and emotional issues, including, but not limited to, post-traumatic stress disorder (PTSD). Borenstein explains that this emotional component could also play a role in the development of rheumatoid arthritis or a similar condition.

“The chronic emotional stress with increased stress hormones or the physical and mental fatigue may also trigger a response,” he said.

Bill Gleason, from the World Trade Center Rescuers Foundation, noted that conditions like RA are not yet listed among the most common health ailments in ground zero workers, though immune system suppression may be.

“The rheumatic and autoimmune conditions are not a commonly reported item, [and are] not on the National Institute for Occupational Safety and Health (NIOSH) list of accepted diseases,” he said. “Immune system depression is becoming more common among the rescuers who have high steroid use, a known treatment side effect, resulting in a higher rate of infection.”

He added this issue is “not just a WTC problem.”

Read more: Scientists Dive Deep Into the Brain to Seek Source of PTSD »

Patient Resources:

Some patients who worked at the World Trade Center site are in an ongoing fight to have their treatment covered by a special 9/11 workers fund. There are several funds set up for 9/11 victims and rescuers. One of the most notable is the James L. Zadroga 9/11 Health & Compensation Act of 2010.

According to the nonprofit 9/11 Health Watch, this fund “provides financial compensation for any individual (or the loved ones of those who have died) who suffered physical harm or was killed as a result of the attacks of September 11, 2001 or the rescue, recovery, and cleanup efforts.”

Other noteworthy resources, registries, and funds include the World Trade Center Health Registry, the World Trade Center Health Program, and the World Trade Center Volunteer Fund. Some workers may have been entitled to workers’ compensation, Line of Duty Injury benefits, or disability benefits.

According to Christina Spring of the CDC, RA is not currently a covered condition under the WTC Health Program. Whether treatments for RA or similar ailments will be covered in other ways, or if these patients would be compensated in the future remains unclear. It would likely be considered on a case-by-case basis, and it may be a problematic effort to prove the link between an RA diagnosis and 9/11.