The study: children with a dog or with multiple siblings are better protected from Crohn’s disease

Young children who grow up with a dog or in a large family are more likely to be protected from a chronic inflammatory bowel disease known as Crohn’s disease, according to a study by Mount Sinai Hospital and the University of Toronto to be presented this week. of Digestive Diseases (DDW) 2022.

“Our study appears to add to others who have explored the hygiene hypothesis which suggests that lack of exposure to microbes early in life can lead to a lack of immune regulation against environmental microbes,” said Williams Turpin. senior author of the study and an associate researcher at Mount Sinai Hospital and the University of Toronto.

To gather information, the researchers used an environmental questionnaire from nearly 4,300 first-degree relatives of people with Crohn’s disease enrolled in the Crohn’s and Colitis Canada Genetic, Environmental, and Microbial (CCC-GEM) project. Using the questionnaire responses and historical data collected at the time of hiring, Dr. Turpin and his team analyzed several environmental factors, including the size of the family, the presence of dogs or cats as pets, the number of bathrooms. in home. The analysis also included age at the time of exposure. The study found that exposure to dogs, particularly ages 5 to 15, was linked to healthy leaky gut and the balance between microbes in the gut and the body’s immune response, which could help protect against the disease. by Crohn. Similar effects were seen with exposure in dogs of all age groups.

Crohn’s disease is a type of inflammatory bowel disease that affects approximately half a million people in the United States. It most often develops in young adults, people who smoke, and those with a close family member who has IBD. Symptoms include diarrhea, abdominal pain, and weight loss. Treatments currently aim to prevent symptom flare-ups through diet modification, medications, and surgery. “We haven’t seen the same results with cats, although we’re still trying to determine why,” Turpin said. It could be because dog owners go out with their pets more often or live in areas with more green space, which has previously been shown to protect against Crohn’s. ‘ Another factor that protects against disease risk is living with three or more family members in the first year of life, which was associated with the composition of a stronger microbiome later in life. The gut microbiome is believed to play a role in a number of health conditions, such as inflammatory bowel disease, colorectal cancer, diabetes and hypertension. The reasons why dog ​​ownership and larger families appear to provide protection from Crohn’s remain unclear. However, the researchers point out that caution is needed in interpreting these results due to possible recall bias at the time of recruitment. In fact, the environmental factors of early childhood were assessed using questionnaires.