Abstract
Objectives
Studies investigating association between manganese (Mn) and type 2 diabetes (T2D) were controverial and relationship between Mn and gestational diabetes mellitus (GDM) remains unclear. We aimed to explore the association between urinary Mn levels and GDM.
Methods
The study population included 2093 singleton pregnant women from Tongji Maternal and Child Health Cohort (TMCHC), a prospective cohort study in China. The maternal urine specimens were collected before 20 weeks of gestation and determined by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Odds ratios (ORs) for GDM were compared according to urinary Mn levels in quartiles using logistic regression after adjusting for potential covariates. Stratified analyses and interactive analyses were conducted. Then restricted cubic spline (RCS) regression was applied. Association between urinary Mn levels and glucose levels was assessed by linear regression.
Results
The medians (interquartile range) (IQR) of urinary gestation and Mn levels were 13.2 (12.2, 15.8) weeks and 0.8 (0.4–1.4) μg/g creatinine (Cr), respectively. A total of 241 (11.5%) participants were diagnosed with GDM. The odds ratios (ORs) and 95% confidence intervals (CIs) of GDM were 1.76 (1.15, 2.71) for the third quartile of urinary Mn levels and 2.00 (1.29, 3.10) for the highest quartile compared with the lowest quartile after adjustment. The adverse effect remained in all the subgroups stratified by age, primigravida, pre-pregnancy BMI, fetal sex, family history of diabetes, BMI at OGTT and physical activity. In RCS, the adverse association was consistently showed. Higher urinary Mn levels were found to be associated with higher fasting blood glucose (FBG) (Ptrend = 0.002) but not post-prandial.
Conclusions
Our findings suggested a positive association between urinary Mn levels and GDM.
Funding Sources
This study is supported by the National Program on Basic Research Project of China and the Fundamental Research Funds for the Central Universities.
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