Search

Conclusions: Our study, for the first time, suggests that vitamin C supplement use or higher dietary vitamin C intake during preconception and early pregnancy could alleviate the risk of GDM associated with exposure to As and Hg. The results warrant further investigation.

Gestational diabetes mellitus (GDM) is a growing public health concern for many reasons, and its etiology remains unclear. Due to the similarity of its pathophysiology with type 2 diabetes (T2DM), we evaluated the relationship between published T2DM susceptibility genes and the risk of GDM. A total of 303 SNPs from genes including IRS1, IGF2BP2, CDKAL1, GCK, TCF7L2, KCNQ1, and KCNJ11 and the risk of GDM were examined in a nested case-control study with 321 GDM cases and 316 controls. The odds ratios (ORs) and their 95% confidence interval (95% CI) were estimated by unconditional logistical regression as a measure of the associations between genotypes and GDM in additive, recessive, dominant, and codominant models adjusting for maternal age, maternal BMI, parity, and family history of diabetes. At the gene level, CDKAL1 was associated with GDM risk. SNPs in the CDKAL1 gene including rs4712527, rs7748720, rs9350276, and rs6938256 were associated with reduced GDM risk. However, SNPs including rs9295478, rs6935599, and rs7747752 were associated with elevated GDM risk. After adjusting for multiple comparisons, rs9295478 and rs6935599 were still significant across the additive, recessive, and codominant models; rs7748720 and rs6938256 were significant in dominant and codominant models; and rs4712527 was only significant in the codominant model. Our study provides evidence for an association between the CDKAL1 gene and risk of GDM. However, its role in the GDM pathogenesis still needs to be verified by further studies.

Identification of modifiable dietary factors, which are involved in the development of gestational diabetes mellitus (GDM), could inform strategies to prevent GDM. Therefore, we examined the dietary nutrient patterns and evaluated their relationship with GDM risk in a Chinese population using a case control study design. A total of 1,464 GDM cases and 8,092 non-GDM controls were included in the final analysis. Dietary intake was assessed using a 33-item food frequency questionnaire, and nutrients were estimated using the Chinese Standard Tables of Food Consumption. Dietary nutrient patterns were identified using factor analysis, and their associations with GDM risk were evaluated using unconditional logistic regression models adjusting for total energy intake, maternal age, high blood pressure, education, maternal body mass index (BMI), parity, and family history of diabetes. A “vitamin” nutrient pattern was characterized as the consumption of diet rich in vitamin A, carotene, vitamin B2, vitamin B6, vitamin C, dietary fiber, folate, calcium, and potassium. For every quartile increase in the vitamin factor score during one year prior to conception, the first trimester, and the second trimester of pregnancy, the GDM risk decreased by 9% (OR: 0.91, 95%CI: 0.86-0.96), 9% (OR: 0.91, 95%CI: 0.86-0.96), and 10% (OR: 0.90, 95%CI: 0.85-0.95), respectively. The significant reduced GDM risk was seen in women regardless of age and parity, and slightly stronger effect was found in women whose age≤30 and women who are nulliparous across the three time periods. The significant association was also found in women whose BMI≤24 with similar effect size across the three time periods. Our study suggests that the vitamin nutrient pattern diet is associated with decreased GDM risk. Additional studies are necessary to explore the underlying mechanism of this relationship.