Functional bowel symptoms in the general population (Review)

Area of Science:

• Gastroenterology
• Microbiome Research
• Public Health

Background:

• Irritable bowel syndrome (IBS) is prevalent, yet many patients do not seek medical care.
• Primary healthcare centers manage most IBS cases, contrasting with tertiary centers for research.
• Understanding IBS triggers and associations in the general population is crucial for effective management.

Purpose of the Study:

• To investigate the associations between self-reported IBS, functional gastrointestinal (GI) symptoms, and various health and lifestyle factors in a large population cohort.
• To explore the relationship between gut microbiome composition (Blautia abundance, beta-diversity) and IBS/GI symptoms.
• To identify medical, sociodemographic, and environmental correlates of IBS and GI symptoms.

Main Methods:

• Analysis of data from over 4,000 participants in the Malmö Offspring Study, including clinical examinations, blood and fecal sample collection, and questionnaires.
• Categorization of participants into groups with and without self-reported IBS and current functional GI symptoms.
• Assessment of zonulin levels, microbiome composition (Blautia abundance, beta-diversity), and correlations with symptom severity and physiological parameters.

Main Results:

• IBS and GI symptoms were strongly associated with each other and positively correlated with Blautia gut bacteria abundance and altered beta-diversity.
• Low birth weight and being small for gestational age correlated with symptom impact on daily life.
• IBS/GI symptoms were linked to female sex, smoking, stress, poor sleep, unemployment, drug use, family history of GI diseases, and inversely to younger age. Zonulin levels showed no significant association.

Conclusions:

• Sociodemographic and environmental factors, including lifestyle and early life conditions, are significantly associated with IBS and functional GI symptoms.
• Limited specific medical findings were identified in individuals with IBS/GI symptoms, highlighting the importance of non-medical factors.
• The gut microbiome, specifically Blautia abundance and beta-diversity, plays a role in the pathophysiology of IBS and GI symptoms.