BMJ: Doctors
may be able to modify or slow down the progress of the neurological
condition Parkinson’s disease in the future by spotting signs of it in
patients with inflammatory bowel disease (IBD), suggest a study
published in the journal Gut. Danish
researchers found patients with IBD appeared to have a 22% greater risk
of developing Parkinson’s disease in a study that monitored
participants for almost 40 years.
IBD, Crohn’s disease and ulcerative colitis are chronic conditions with onset in young adulthood.
It
has already been suggested in previous studies that inflammation plays a
role in the development of Parkinson’s disease and multiple system
atrophy.
Enteric
inflammation – the main symptom of inflammatory bowel disease – can
occur in patients with Parkinson’s disease and may reflect the earliest
manifestations of the neurological condition’s development.
Experts
have suspected for some time that there may be a ‘gut-brain axis’ where
the intestinal environment influences the functioning of the central
nervous system and intestinal imbalance may precede and cause
Parkinson’s disease.
Therefore,
a team of Danish researchers led by Dr Tomasz Brudek of the Research
Laboratory for Stereology and Neuroscience, Bispebjerg and Frederiksberg
Hospital, Copenhagen, set out to examine whether IBD was associated
with risk of Parkinson’s disease and multiple system atrophy.
They
carried out a nationwide population-based cohort study involving all
individuals diagnosed with IBD in Denmark between 1977 and 2014 – 76,477
people – and more than 7.5 million non-IBD individuals from the general
population, who were comparable in terms of gender, age and vital
status.
All
participants were followed from IBD diagnosis/index date to the
occurrence of Parkinson’s disease and multiple system atrophy, using
data from the Danish National Patient Register.
During
the 37-year study period, 335 patients with IBD (0.4%) and 39,784
non-IBD individuals (0.5%) were diagnosed with Parkinson’s disease,
whereas 13 patients with IBD (0.02%) and 866 non-IBD individuals (0.01%)
were diagnosed with multiple system atrophy.
Analysis
of the results showed that patients with IBD had a 22% higher risk of
Parkinson’s disease compared with non-IBD individuals.
This increased risk was present independent of age at IBD diagnosis, gender or length of follow-up.
The
overall incidence of multiple system atrophy was low in the study, but
analysis suggested a tendency towards higher risk (41% higher) of
developing multiple system atrophy in patients with IBD compared with
non-IBD individuals. The estimates were similar for women and men.
There
was a 35% greater risk of parkinsonism among patients with ulcerative
colitis but not a significantly higher risk among patients with Crohn’s
disease.
This
was an observational study, so no firm conclusions can be drawn about
cause and effect, but the authors said they believed their work was the
first epidemiological study investigating the risk of parkinsonism in an
unselected, nationwide cohort of patients with IBD with long-term
follow-up – patients were followed for more than 8 million person-years.
The
authors concluded: “The study suggests that clinicians should be aware
of symptoms of parkinsonism in patients with IBD, and the study
demonstrates the need for further investigation into the role of
intestinal inflammation and brain gut-microbiome axis in the aetiology of parkinsonism.
“The
identification of risk factors associated with prodromal phases of
Parkinson’s disease may allow for early intervention studies that could
modify or slow down disease progress.”
[Ends]
Journal: Gut