A Global Perspective of Correlation Between Maternal Copper Levels and Preeclampsia in the 21st Century: A Systematic Review and Meta-Analysis

Pregnancy Metal Mixtures and Blood Pressure and Hypertension in Mid-Life: A Prospective U.S. Cohort Study

BACKGROUND

The long-term associations between metal mixtures in pregnancy and women's mid-life blood pressure (BP) and hypertension remain unclear.

METHODS

In Project Viva (enrolled 1999-2002), we measured nonessential (arsenic, barium, cadmium, cesium, mercury, lead) and essential metals (copper, magnesium, manganese, selenium, zinc) in red blood cells, along with folate and vitamin B12 in plasma, collected during pregnancy. We measured mid-life BP from 2017 to 2021 (median age, 51.2 years). We examined associations of individual metals with BP using linear regression and with hypertension (≥130/80 mm Hg or use of antihypertensive medication) using modified Poisson regression. We used Bayesian kernel machine regression to examine the mixture effects of metals and micronutrients.

RESULTS

The median follow-up time of the 493 women was 18.1 years (interquartile range, 17.8-18.6 years). After adjustment, a doubling of copper and manganese was associated with 0.75 (95% CI, 0.57-0.99) and 0.80 (95% CI, 0.71-0.91) times the risk of hypertension, respectively. Although higher cesium and selenium levels were associated with a slightly increased risk of hypertension, the 95% CIs were wide and crossed the null. A doubling of vitamin B12 was associated with a 3.64 (95% CI, 1.23-6.04) mm Hg lower systolic BP and a 2.52 (95% CI, 0.72-4.32) mm Hg lower diastolic BP. Bayesian kernel machine regression showed linear associations with no metal-metal or metal-micronutrient interactions. The essential metal mixture was monotonically associated with lower BP, while its association with hypertension showed threshold effects.

CONCLUSIONS

Optimizing essential metal levels during pregnancy, particularly copper and manganese, along with vitamin B12, may protect against higher BP and hypertension in mid-life women.

An exploratory study on the association of multiple metals in serum with preeclampsia

Background

Individual metal levels are potential risk factors for the development of preeclampsia (PE). However, understanding of relationship between multiple metals and PE remains elusive.

Purpose

The purpose of this study was to explore whether eight metals [zinc (Zn), manganese (Mn), copper (Cu), nickel (Ni), lead (Pb), arsenic (As), cadmium (Cd), and mercury (Hg)] in serum had a certain relationship with PE.

Methods

A study was conducted in Dongguan, China. The concentrations of metals in maternal serum were assessed using inductively coupled plasma mass spectrometry (ICP-MS). Data on various factors were collected through a face-to-face interview and hospital electronic medical records. The unconditional logistic regression model, principal component analysis (PCA) and Bayesian Kernel Machine Regression (BKMR) were applied in our study.

Results

The logistic regression model revealed that the elevated levels of Cu, Pb, and Hg were associated with an increased risk of PE. According to PCA, principal component 1 (PC1) was predominated by Hg, Pb, Mn, Ni, Cu, and As, and PC1 was associated with an increased risk of PE, while PC2 was predominated by Cd and Zn. The results of BKMR indicated a significant positive cumulative effect of serum metals on PE risk, with Ni and Cu exhibiting a significant positive effect. Moreover, BKMR results also revealed the nonlinear effects of Ni and Cd.

Conclusion

The investigation suggests a potential positive cumulative impact of serum metals on the occurrence of PE, with a particular emphasis on Cu as a potential risk factor for the onset and exacerbation of PE. These findings offer valuable insights for guiding future studies on this concern.