• Environmental Associations in Paediatric Inflammatory Bowel Disease (IBD)

    The incidence of paediatric IBD is increasing in most countries that record this information. Countries with the highest number of cases are within Europe and North America. The reasons for the increase is unclear; although there is a genetic component to IBD, genes evolve over hundreds of years and this would not be sufficient to explain the significant rate of rise that researchers are reporting. There are numerous theories which, researchers believe, may explain this increase, including environmental factors: e.g. urban versus rural locations, number of siblings, and level of wealth. A recent study by researchers in Finland looked at whether the risk of IBD is higher in an industrial or heavily populated area compared to a more remote and sparsely populated area.1 It found a higher rate of paediatric IBD in areas with smaller populations, which is an interesting observation and one that has been noted previously in Scotland. The researchers were unable to pinpoint exactly why this occurs, ruling out factors such as closeness to paper mills, chemical contaminants of tap water, and distance from the seaside, concluding that it was likely to be a result of multiple factors. Their findings contradict studies conducted in other countries, such as Canada, Norway and the US, which reported higher rates in urban areas rather than remote areas. The reasons for the discrepancies are unclear, but may relate to different environmental factors, changes in methods of diagnosis, or differing genetics of the population. It is unlikely that one single cause will be identified as causing IBD. It is more likely that a complex interaction between the environment and gut bacteria triggers the onset of IBD symptoms in genetically susceptible individuals. Epidemiological studies such as this − which examine different environmental risk factors − are crucial to our understanding of causes of paediatric IBD. By increasing our understanding of these triggers, we may be able to identify those at increased risk.

    FC

    1 http://europepmc.org/abstract/med/26636498