Investigating the causal effect of various metabolites on postherpetic neuralgia: a Mendelian randomization study

The results of this study indicated a significant association between <i>N</i>-acetyl-aspartyl-glutamate (NAAG) and PHN, with an odds ratio (OR) of 0.83 (95% CI: 0.76-0.91, <i>p</i> = 2.68E-05). Furthermore five possible related metabolites were found: Glutamylthreonine gamma-wise (OR = 1.60, 95% CI: 1.16-2.20, <i>p</i> = 0.004), 3-hydroxyphenylacetoylglutamine (OR = 1.43, 95% CI: 1.00-2.05, <i>p</i> = 0.048), Caprate (10:0) (OR = 1.86, 95% CI: 1.11-3.12, <i>p</i> = 0.018), X-12013 (OR = 1.64, 95% CI: 1.03-2.60, <i>p</i> = 0.035), and X-17328 (OR = 1.50, 95% CI: 1.04-2.18, <i>p</i> = 0.032). Furthermore, in the causal pathway NAAG most certainly serves as a complete mediator between FOLH1(CGPII) and postherpetic neuralgia.