#ADHD #gut #IBS #GutBrainAxis #Microbiome
Attention-deficit/hyperactivity disorder (ADHD)
is a chronic neurodevelopmental disorder that begins in childhood and may
persist into adulthood. Affecting up to 14% of children and nearly 7% of
adults, it is associated with numerous
psychiatric and medical comorbidities,
including
gastrointestinal disorders.
Digestive symptoms such as constipation and
flatulence have been reported in patients with ADHD. However, their etiological
link remains uncertain. Despite increasing attention on the role of the gut
microbiome in neuropsychiatric disorders,
data connecting ADHD and intestinal
disorders remain limited and inconsistent. Understanding the role of the
microbiota and the
gut-brain axis in ADHD could therefore open new diagnostic
and therapeutic avenues. Nevertheless, the diversity of studies, diagnostic criteria,
and geographical regions studied complicates result interpretation.
This study was conducted to synthesize and
characterize a potential association between ADHD and various intestinal
disorders (notably irritable bowel syndrome, celiac disease, IBD, etc.), by
evaluating relative risks in different regions of the world.
Does ADHD upset the gut?
Eleven studies conducted between 2000 and 2023
were selected, including a total of 3.85 million participants, 175,806 of whom
had ADHD. The studies included cohort, case-control, and cross-sectional
designs, and were assessed for quality using the JBI tool.
The findings suggest a trend toward an
increased risk of intestinal disorders in individuals with ADHD, although the
association was not statistically significant due to high heterogeneity among
studies. However, a
significant relationship was observed between ADHD and
irritable bowel syndrome (IBS), confirming a higher prevalence of this
functional disorder in ADHD patients. No clear correlation was found for celiac
disease, constipation, or chronic inflammatory bowel diseases (IBD).
Subgroup analysis by region revealed
notable
geographical disparities, with the Eastern Mediterranean region showing a
stronger association compared to the Americas, Europe, or Western Pacific.
Finally, sensitivity analysis strengthened the robustness of the
ADHD-intestinal disorders link, with the association reaching statistical
significance.
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From neurons to the colon: a connection worth
exploring!
ADHD is a common and chronic condition with
complex and
multifactorial origins. Genetic factors, inflammatory mechanisms,
and environmental influences play significant roles.
Gastrointestinal
disorders, particularly
irritable bowel syndrome (IBS), are a major concern
among patients with ADHD. Their presence can significantly impair quality of
life and complicate treatment, especially when medications like methylphenidate
are associated with digestive side effects such as abdominal pain.
This study aimed to
clarify the statistical
association between ADHD and various intestinal disorders and to
explore the
potential role of the gut microbiota as a pathogenic mediator in this
association. Although the results do not establish a strong correlation between
ADHD and all intestinal disorders, they do confirm a
significant association
with IBS. This relationship suggests the
possible involvement of the gut
microbiome as a central factor in the neurological and digestive dimensions of
ADHD.
However, several limitations temper the
interpretation of these results and underscore the
need for further research.
Future studies are needed to better understand the
interactions between
microbiota and ADHD. Exploring the therapeutic potential of microbiota-targeted
interventions—such as probiotics, prebiotics, or synbiotics—represents a
promising avenue for improving the overall management of patients.
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