UEG Week: New research links Crohn’s disease to Black Death

European incidence of Crohn’s disease is likely to be a result of surviving the Black Death in the middle ages, according to new research presented today at the 26th UEG Week in Vienna. 

Researchers from Paris, France studied historical data on the intensity of plague outbreaks from Europe and the Mediterranean Basin between 800 and 1850AD. They found that there was statistical significance between outbreak intensities and Crohn’s disease-associated mutations in the general population – which help to explain modern-day prevalence of Crohn’s disease in Europe.

Crohn’s disease is a chronic relapsing condition that, together with ulcerative colitis, comprises the disease known as inflammatory bowel disease (IBD). The researchers looked at the gene NOD2 which plays an important role in the body’s immune system but mutations of which are related to the development of Crohn’s disease. Mutations of NOD2 have been shown to aid the resistance of the organism that causes the plague and the results of the study show that the prevalence of these mutations associated with Crohn’s disease are correlated with the intensities of plague outbreaks.

Approximately 3 million Europeans are now affected by IBD, which costs European health systems up to €5.6 billion per year. The causes of IBD are not fully known, although research strongly suggests that both genetic and environmental factors play a significant role. IBD can lead to an increased risk of developing colorectal cancer and, whilst symptoms may develop at any age, the peak age of IBD onset is during adolescence or early adulthood.

The Black Death was responsible for the deaths of millions of Europeans and is thought to have killed between 30-40% of the European population between 1347 and 1353.

Professor Jean-Pierre Hugot, one of the leading researchers involved in the French study explains, “Considering the potential severity of Crohn’s disease when untreated, it is unlikely that it was a frequent disease before the 20^th century. As healthcare systems have developed and care for Crohn’s disease patients has improved, more and more people are living with the disease. This research goes some way to explaining the genetic origins of Crohn’s and we hope it will enable us to better understand the disease, and how to treat it, in the future.”