Associations of metal exposure with chest pain incidence and mortality in nonpregnant adults: Based on NHANES data

Heavy metals are widespread environmental contaminants that have attracted considerable attention because of the potential human health risks. Heavy metals can lead to cardiovascular disease and chest pain is the most common precursor symptom. The study aimed to investigate the association between metal exposure and chest pain. This cross-sectional study used data obtained from the 2003 to 2012 National Health and Nutrition Examination Survey. Three metals: lead (Pb), cadmium (Cd), mercury (Hg) in the blood and ten metals: barium (Ba), Cd, cobalt (Co), cesium (Cs), molybdenum (Mo), Pb, antimony (Sb), thallium (Tl), tungsten (Tu), uranium (Ur) in the urine were studied. Using weighted logistic regression models, the relationship between the metal exposure and chest pain was investigated. The hazard ratios (HR) and 95% confidence intervals (95% CI) for all-cause mortality were calculated by weighted Cox proportional hazards models. By applying restricted cubic spline (RCS) analysis, we confirmed linear or nonlinear relationships between metal exposure and all-cause mortality. After adjusting for potential confounding factors, our study found a significant positive association between urinary Sb concentration and chest pain (quartile 4 vs quartile 1, odds ratio [OR] 1.55, 95% CI: 1.02-2.35, P = .042). Additionally, each 1-unit increase in blood Cd concentration was associated with a 22% increased risk of all-cause mortality (HR: 1.22, 95% CI: 1.01-1.48). Additionally, RCS analysis showed a nonlinear relationship between the urine Sb concentration and chest pain (P for nonlinear = .0009). A linear relationship was revealed between the urine Cd concentration and all-cause mortality in participants without chest pain (P for nonlinear = .0858). We observed higher odds of chest pain in participants with elevated urinary Sb concentrations, with those in the highest quartile of Sb concentration showing 55% increased odds of chest pain compared to the lowest quartile (OR: 1.55, 95% CI: 1.02-2.35, P = .042). Besides, urinary Sb concentration levels were significantly associated with chest pain. Cd concentration levels in the blood and urine were associated with all-cause mortality. This study explored the associations between metal exposure and chest pain incidence, as well as all-cause mortality. However, due to the cross-sectional design, causality cannot be established.