ANXIETY increases the risk of gastrointestinal infection and long-term complications, according to the results of an investigation of a massive drinking water contamination incident in Belgium in 2010. The findings were made by a team comprised of scientists at the Flemish Institute for Biotechnology (VIB), KU Leuven, and UZ Leuven, and represent significant progress made in uncovering the connection between psychological factors and the immune system.
In December 2010, the Belgian communities of Schelle and Hemiksem in the province of Antwerp faced an outbreak of gastroenteritis, with >18,000 people exposed to contaminated drinking water. During the outbreak, VIB and KU Leuven set up a scientific task force to study the long-term effects of the incident, led by Prof Guy Boeckxstaens (KU Leuven/UZ Leuven) and Prof Adrian Liston (VIB/KU Leuven).
Prof Adrian Liston, Autoimmune Genetics Laboratory, VIB and Department of Microbiology and Immunology, KU Leuven, Leuven, Belgium, said: “The water contamination in Schelle and Hemiksem was an ‘accidental experiment’ on a scale rarely possible in medical research. By following the patients from the initial contamination to a year after the outbreak we were able to find out what factors altered the risk of long-term complications.”
The researchers discovered that individuals with higher levels of anxiety or depression prior to the water contamination developed GI infections of increased severity. They also displayed an increased risk of developing the long-term complication of irritable bowel syndrome, with intermittent abdominal cramps, diarrhoea, or constipation a year after the initial contamination.
Prof Guy Boeckxstaens, Department of Gastroenterology, Translational Research Center for Gastrointestinal Disorders, University Hospital Leuven, KU Leuven, said: “Irritable bowel syndrome is a condition of chronic abdominal pain and altered bowel movements. This is a common condition with large socio-economic costs, yet there is so much that still remains to be discovered about the causes. Our investigation found that anxiety or depression alters the immune response towards a gastrointestinal infection, which can result in more severe symptoms and the development of chronic irritable bowel syndrome.”
The study findings provide valuable new insight into the cause of irritable bowel syndrome, highlighting the link between psychological factors and the immune system. “These results once again emphasise the importance of mental healthcare and social support services. We need to understand that health, society, and economics are not independent, and ignoring depression and anxiety results in higher long-term medical costs,” added Prof Liston.