Higher exposure to residential greenspace in childhood is associated with a reduced risk for pediatric-onset inflammatory bowel disease (IBD), according to a study published in the American Journal of Gastroenterology. Investigators conducted a retrospective cohort study using linked population-based health administrative and environmental data sets. A total of 2,715,318 mother-infant pairs from hospital births in Ontario between April 1, 1991, and March 31, 2014, were included. Exposure to residential greenspace was measured, and the potential associations between residential greenspace and risk for developing IBD before age 18 were examined. During follow-up, there were 3,444 IBD diagnoses. The researchers observed an association between a lower risk for developing pediatriconset IBD and an increase in the interquartile range of residential greenspace (hazard ratio [HR], 0.77). This association was significant for ulcerative colitis and Crohn’s disease (HRs, 0.72 and 0.81, respectively). Across increasing quartiles of greenspace, there was a linear dose response. No consistent association was seen between maternal intrapartum greenspace exposure and pediatric-onset IBD. “Greenspace is an emerging area in environmental health research, and this study is the first to investigate and report its protective effect with IBD,” the authors write.

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