Joint effects of folate and vitamin B12 imbalance with maternal characteristics on gestational diabetes mellitus

Background This study examined whether folate and vitamin B12 imbalance is associated with gestational diabetes mellitus (GDM) and explored interactions between B vitamin imbalance and maternal risk factors for GDM. Methods A cross‐sectional study was performed in 406 Chinese pregnant women. Serum folate, vitamin B12, and blood glucose concentrations were measured at 24 to 28 weeks gestation during GDM screening. A diagnosis of GDM was made based on International Association of Diabetes and Pregnancy Study Groups criteria (fasting plasma glucose [FPG] ≥5.1 mM, 1‐hour plasma glucose ≥10.0 mM, or 2‐hour plasma glucose ≥8.5 mM). Binary logistic regression was used to obtain odds ratios (ORs) after controlling for different confounders. Results Higher folate levels were associated with higher glucose concentrations and a higher risk of GDM (OR 1.98; 95% confidence interval [CI] 1.00‐3.90), whereas higher vitamin B12 levels were associated with lower FPG and a lower risk of GDM (OR 0.30; 95% CI 0.15‐0.60). A higher folate: vitamin B12 ratio was associated with higher glucose and a higher risk of GDM (OR 3.08; 95% CI 1.63‐5.83). The presence of both a higher folate: vitamin B12 ratio and advanced age further increased the OR to 2.13 (95% CI 1.09‐4.15) with a significant additive interaction. Furthermore, a higher folate: vitamin B12 ratio and a higher prepregnancy body mass index (pp‐BMI) were synergistically associated with an increased risk of GDM (OR 3.03; 95% CI 1.40‐6.57). Conclusions An imbalance between folate and vitamin B12, represented by a higher folate: vitamin B12 ratio, was highly associated with GDM risk, and this association could be further modified by maternal age and pp‐BMI. 摘要 背景 本研究探讨了叶酸和维生素B12失衡与妊娠期糖尿病(gestational diabetes mellitus, GDM)之间的关系, 同时进一步研究了B族维生素失衡与母体危险因素交互作用对GDM的影响。 方法 采用横断面研究的方法, 以406名开展GDM筛查的孕妇为研究对象, 在孕24‐28周检测其血清叶酸、维生素B12和血糖水平。依据国际糖尿病和妊娠研究协会的标准对GDM进行诊断(空腹血糖[FPG]≥ 5.1 mM, 1小时血糖≥ 10.0 mM, 或2小时血糖≥ 8.5 mM)。采用二元logistic回归分析并获得控制不同混杂因素后的OR值。 结果 血清中较高的叶酸水平与较高的血糖浓度相关, 且与GDM发生风险增加有关(OR:1.98；95% CI:1.00‐3.90)；而较高的维生素B12水平与较低的FPG水平相关, 且与GDM发生风险降低有关(OR:0.30；95%CI:0.15‐0.60)。同时较高的叶酸:维生素B12比值与高血糖和GDM发生风险增加也显著相关(OR:3.08；95% CI:1.63‐5.83)。进一步研究表明, 较高的叶酸:维生素B12比值与高龄孕妇存在交互作用, 可以增加GDM的发生风险(OR:2.13；95% CI:1.09‐4.15)；且较高的叶酸:维生素B12比值和较高的孕前BMI也可以协同增加GDM发生的风险(OR:3.03；95% CI:1.40‐6.57)。 结论 叶酸和维生素B12失衡(以较高的叶酸:维生素B12比值为特征)与GDM发生风险增加密切相关, 且孕妇年龄和孕前BMI可以进一步影响二者之间的关系。 Highlights Higher folate and lower vitamin B12 levels were associated with higher glucose