Associations of multiple blood metals with cardiac structure and function: A cross-sectional study in a CAD...

Coronary artery disease (CAD) is often accompanied by abnormal cardiac structure and function, leading to an increased prognostic risk. However, less is known about the associations of mixed metals with abnormal cardiac structure and function in CAD patients. Here, we aimed to investigate the associations of exposure to metal mixtures with cardiac structure and function and potential interactions in a CAD population. We conducted a cross-sectional study from Southwest China that included 1555 CAD patients. The blood concentrations of 14 metals were measured via inductively coupled plasma spectrometry. CAD was defined as at least one vessel having stenosis ≥50% the vessel diameter. Echocardiography was used for cardiac structural and functional measurements. Bayesian kernel machine regression was applied to explore the overall effect, metal weight, and dose effect. Linear regression analysis was used to analyze the effects of single metals, metal‒metal interactions and metal‒traditional interactions. Finally, we found that the negative associations of mixed metals with cardiac structure was significant when the levels of all metals were below the 60th percentile. For cardiac function, changes in metals from 50th to 75th were associated with 0.954% and 0.683% decrease in left ventricular ejection fraction and left ventricular fractional shortening, respectively. Negative associations of copper and manganese with cardiac structure and function, whereas positive associations of titanium, selenium and molybdenum with several parameters were found. Antagonistic interactions between copper and tin and between selenium and several metals (manganese, copper and aluminum) (all P_{interaction terms} < 0.05) were found. In conclusion, mixed metal exposure was negatively associated with cardiac structure and function in CAD patients. The main metals contributing to this negative associations were copper and manganese. Selenium or tin supplementation may reduce the adverse associations of copper and manganese with cardiac structure and function.