Lauren Collen, MD: Some Fragrances May be More Prevalent in Exposomes of Children with Crohn’s Disease

Early findings of a preliminary analysis indicate some plastics and fragrances may be more prevalent in the exposomes of patients aged 0 – 18 years with Crohn’s disease, compared with age-matched controls. However, since this study is still in the early stages of research with only a small sample size, the findings are not statistically significant.

Investigator Lauren Collen, MD, from Boston Children’s Hospital, talked about the early data in an interview with HCPLive at the 2024 Annual North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition (NASPGHAN) Meeting in Hollywood, Florida, from November 7 to 9, 2024.

“I think the initial step here is to understand the big picture, what some of the environmental triggers of inflammatory bowel disease are, and then certainly down the line, therapeutics or preventative measures might target those specific exposures, but I think we're a couple steps away from that,” Collen said.

The incidence of various inflammatory bowel disease (IBD) subtypes, including Crohn’s Disease, has increased in early life over the past 2 decades. However, with only 15% of patients having monogenic etiologies for very early onset IBD, the disease increase cannot solely be explained by genetics—the environment plays a role, too.

Environmental exposures influence an infant’s immune response and can increase susceptibility to immune-mediated diseases. Biological, chemical, physical, and psychosocial factors all come together to create an exposome. Previous research has evaluated the association between Crohn’s disease and individual environmental risk factors, such as pathogens, pharmaceuticals, psychological stress, diet, and chemicals, but the results were inconclusive.

Collen and colleagues are conducting a prospective study to evaluate the role of environmental influences on Chrohn’s disease susceptibility by examining exosomes. They conducted an exposomic tool, the Fresh Air sampler, that could comprehensively capture personal exposures to chemical contaminants from air, water, consumer products, combustion activity, building materials, furnishing, clothing, diet, and pharmaceutical sources. Investigators used this tool with high-resolution mass spectrometry to analyze the occurrence and distribution of thousands of environmental chemicals.

In July 2022, the team recruited 180 patients recently diagnosed with Crohn’s disease and 180 sex-and age-matched controls through the VEO-IBD Consortium at Boston Children’s Hospital, The Hospital for Sick Children, and the Children’s Hospital at Ludwig Maximilians-University of Munich. The exposome was characterized in 45 patients.

The Fresh Air sampler, worn on the ankle for patients < 3 years and worn on the wrist for older patients for 5 days, detected exposures from various locations, such as school, home, and outdoors. The sampler contains a polytetrafluoroethylene case that houses polydimethylsiloxane (PDMS) sorbent bars that collect airborne contaminants.

The samplers demonstrated participants were exposed to 5954 features, including oxygenated alkanes, as well as aromatic and oxygenated hydrocarbons. A Cheminformatics analysis identified 58 endocrine disrupters and 67 chemicals with predicted genotoxicity, such as phthalates, benzoates, and salicylates, in exposures. The study also showed most exposed chemicals were antimicrobials, preservatives, colorants, and flavorant in personal care, household care, and cleaning products.

Colleen said the team is looking for differences in exposures such as fragrances, pesticides, smoke, pollution, furnishings, and food additives. With the study still ongoing, the team aims to recruit ≥ 300 more patients.

“We're still recruiting at 6 different sites, and so we're excited to engage with patients with recently diagnosed Crohn's disease,” Collen said. “We're hoping to get more patients to wear these bracelets so that we have more data to analyze and present at a future meeting.”

References

^{Collen, L, Barhouma, S, Bearup, R, et al. Exploring Exposome Profiles For Early Life Crohn's Disease. Presented at NASPHGAN 2024 in Hollywood, Florida, from November 7 – November 9, 2024.}