Exploring the causal role of plasma metabolites in pediatric asthma: a Mendelian randomization study

Pediatric asthma (PA) is the prevailing chronic respiratory ailment in childhood. A better understanding of plasma metabolites is the goal for elucidating the molecular pathological mechanisms of PA and investigating novel therapeutic approaches. Data for PA from Genome-Wide Association Studies (GWAS) was derived from the IEU-OpenGWAS project, featuring a collection of 1400 plasma metabolites. The inverse-variance weighting (IVW) method assessed causal relationships between plasma metabolites and PA, with measures taken to mitigate horizontal pleiotropy and heterogeneity. To select instrumental variables, a genome-wide significance threshold ( p < 5 × 10–8) was applied to ensure robust genetic instruments. A Bonferroni correction controlled for multiple testing, with statistical significance defined as p < 3.57 × 10–5) (0.05/1400). To further substantiate outcomes, a reverse Mendelian randomization analysis was conducted. Research found 91 plasma metabolites linked to PA, ten of which showed significant associations. Of note, 20:4n6 levels (IVW: OR (95% CI) = 1.062 (1.030 to 1.094) and G/C16 (IVW: OR (95% CI) = 0.886 (0.832 to 0.943) were identified as pivotal exposure factors for PA. This study highlights 10 plasma metabolites that may have significant associations with PA incidence, with 20:4n6 levels and G/C16 potentially serving as valuable biomarkers for the early detection and management of PA.