Helicobacter pylori colonization and obesity - a Mendelian randomization study

Area of Science:

• Epidemiology
• Genetics
• Microbiology

Background:

• Obesity is a growing global health concern with significant morbidity and mortality.
• Helicobacter pylori (H. pylori) colonization has been inconsistently linked to body mass index (BMI) in prior studies.
• Understanding the etiological factors of obesity is crucial for effective prevention strategies.

Purpose of the Study:

• To investigate the relationship between H. pylori colonization and BMI/obesity.
• To determine if H. pylori infection causally influences BMI or obesity.
• To analyze associations in large, independent population cohorts.

Main Methods:

• Cross-sectional analysis of 13,044 elderly individuals from Dutch and German cohorts.
• Bi-directional Mendelian randomization using genetic risk scores for H. pylori and BMI/obesity.
• Meta-analysis of anti-H. pylori IgG titer and H. pylori positivity with BMI and obesity metrics.

Main Results:

• No association was found between anti-H. pylori IgG titer and BMI, or H. pylori positivity and BMI.
• A weak negative association was observed between anti-H. pylori IgG titer and obesity (OR 0.99972, p=0.03).
• Mendelian randomization provided no evidence for a causal relationship between H. pylori genetic predisposition and BMI/obesity, or vice versa.

Conclusions:

• This study found no clinically relevant association between H. pylori colonization and BMI or obesity.
• The observed weak associations with obesity were limited in magnitude.
• Genetic analysis further supported the lack of a causal link between H. pylori and obesity.