People suffering from with a common gut condition have double the risk of dementia than the general population, a new study has found.
And those patients with inflammatory bowel disease (IBD) – including ulcerative colitis and Crohn’s disease – are likely to be diagnosed with the condition earlier in their lives, researchers found.
The study said evidence is growing to support “reciprocal communication” between the gut and central nervous system in disease, termed the “gut-brain axis”.
Previous studies have found a link between IBD and Parkinson’s disease, so researchers in Taiwan probed links between IBD and dementia.
Using a national database, 1,742 IBD patients were identified and compared with more than 17,000 people without this condition. They were tracked for 16 years to see whether they developed dementia.
Just 1.4 per cent of people in the control group went on to develop dementia compared with 5.5 per cent of patients with IBD.
After taking account of potentially influential factors, including age and underlying conditions, people with IBD were more than twice as likely to develop dementia.
Patients with IBD were diagnosed with dementia at 76 years old on average, compared with 83 years of age among the control group.
Commenting on the study, Dr Rosa Sancho, head of research at Alzheimer’s Research UK, said: “As surprising as it may be, current research suggests the gut and the brain are linked through what is termed the gut-brain axis.
“The brain doesn’t operate in isolation from the rest of the body and inflammation plays a role in the development of the diseases like Alzheimer’s that cause dementia.
“While this research suggests having inflammatory bowel disease increased the risk of dementia, further research is needed before we can be sure about cause and effect.
“A better understanding of the dementia risk in people with inflammatory bowel disease may help improve dementia diagnoses and get treatments to people who need them at the earliest opportunity.
“Only through research like this will we keep people connected to their families, their worlds and themselves for longer.”
Fiona Carragher, director of research at Alzheimer’s Society, said: “If we can understand more about this complex relationship between brain and gut health, it could open up new approaches to tackling dementia, which affects 850,000 people in the UK.”