First responders to the site of the 2001 World Trade Center attack may have an elevated risk of nonalcoholic fatty liver disease (NAFLD), according to investigators.
In a retrospective look at 236 first responders presenting with gastrointestinal symptoms to the World Trade Center Health Program, 195 (82.6%) had NAFLD, compared with 24%-45% of the general population, reported lead author Mishal Reja, MD, of Robert Wood Johnson University Hospital, New Brunswick, N.J.
The increased rate of NAFLD among first responders is likely because of toxin exposure at ground zero, which can cause a subtype of NAFLD known as toxin-associated fatty liver disease (TAFLD), Dr. Reja wrote in an abstract released as part of the annual Digestive Disease Week®, which was canceled because of COVID-19.
“I was not surprised [by these findings],” Dr. Reja said during a virtual press conference. “In the prior literature that did examine TAFLD, it did show that populations exposed to these specific chemicals ... at the ground zero site had extremely high rates – consistent with the rates we found in our study – of fatty liver disease.”
Dr. Reja said that 9/11 first responders were exposed to “many common toxins that are consistently in occupational and environmental toxicant literature.” In particular, he named polycyclic aromatic hydrocarbons and vinyl chloride.
“A lot of these toxins are ... included in industrial solvents as well as building demolition,” Dr. Reja said. “So they’ve been around for so long, and they’ve been studied for so long, [that we have] literature that shows these toxins are associated with fatty liver disease, which is how we arrived at the hypothesis in the first place.”
The first responders were stratified by roles, which were associated with varying levels of exposure. About 40% of individuals in the study were involved in moving debris from the site, a small group (4%) were involved in clean-up and maintenance, while approximately 30%-40% worked in more protected, administrative roles.
Comparing individuals in the study with TAFLD versus those without TAFLD revealed additional risk factors. Multivariate logistical regression analysis showed that obese individuals had a significantly increased risk of fatty liver disease, suggesting a synergistic effect.
“If you were exposed to these toxins in the World Trade Center, and you were obese, [then] you are actually between two to three times more likely to get [TAFLD],” Dr. Reja said, noting that hypertension and diabetes were also identified as independent risk factors.
Dr. Reja and colleagues are planning a prospective trial to investigate further. The study will likely involve 100-200 first responders with TAFLD, a similar number of individuals with NAFLD, and another group without liver disease.
The investigators reported no outside funding or conflicts of interest.
SOURCE: Reja M et al. DDW 2020, Abstracts available online May 2.
