Association of miR-124 polymorphism with labor analgesia in primiparas

OBJECTIVES: Genetic polymorphism may influence the efficacy of analgesia during labor anesthesia. This study employed a retrospective case-control study design and aimed to investigate the potential influence of the miR-124 rs531564 polymorphism on the efficacy of labor analgesia in primiparous women. MATERIAL AND METHODS: 100 primiparas were enrolled as study participants, all of whom received epidural sufentanil for analgesia. Genotyping was performed using the PCR-LDR, while RT-qPCR was employed to measure the miR-124 expression. The analgesic efficacy (assessed by VAS score), plasma concentration of sufentanil, and incidence of adverse reactions were compared among parturients with different genotypes. RESULTS: In this study, the CC genotype was observed in 53% of participants, the CG genotype in 36%, and the GG genotype in 11%. Individuals with the CC genotype exhibited a higher VAS score at 1-hour post-administration (indicating a poorer analgesic response) and lower 1-minute Apgar scores. Primiparas carrying the CC genotype had reduced miR-124 expression, suggesting that the C allele might contribute to the physiological mechanisms of labor analgesia through down-regulation of miR-124. Moreover, individuals with the CC genotype showed lower sufentanil blood concentrations during the mid-phase of administration (15-20 minutes), which could be attributed to faster drug metabolism or clearance, leading to suboptimal plasma levels - possibly explaining the observed diminished analgesic effect (as indicated by the elevated VAS score at 1 hour). In contrast, primiparas carrying the G allele demonstrated higher sufentanil concentrations at the same time point, correlating with improved analgesic outcomes. CONCLUSIONS: The miR-124 rs531564 polymorphism may influence the efficacy of labor analgesia.