Abstract 4147117: Impact of Heavy Metal Exposure On Cardiovascular Disease Mortality

Background: Cardiovascular disease (CVD) is the primary cause of mortality worldwide, and heavy metal exposure, including lead (Pb), cadmium (Cd), and mercury (Hg), significantly impacts this global burden of disease. Heavy metal-related cardiovascular toxicity results from their ability to induce oxidative stress, inflammation, endothelial dysfunction, and dysregulation of lipid metabolism. We aim to investigate the cardiovascular disease mortality associated with high blood levels of Pb, Cd, and Hg. Method: Using the 1999–2018 National Health and Nutrition Examination Survey (NHANES) data, we examined the association of blood Pb, Cd, and Hg levels with CVD mortality. Pb, Cd, and Hg levels were transformed into quartiles. Mortality hazard ratios were calculated using Cox proportional multivariate regression models adjusting for confounders identified by way of univariate analysis and from literature. Survival across quartiles of Pb, Cd, and Hg levels are depicted using K-M curves. Survival probabilities were compared using KM curves. All analyses were conducted using STATA version 17.0 Results: The study population comprised 55,081 participants spanning over 20-years period, among whom 2401 (4.36%) experienced CVD related to Pd, Cd, and Hg exposure. Of the participants, 48% were male, with the majority being White participants, followed by Hispanic and Black participants. Most participants (82.4%) had a college education or higher, 53.2% were from high-income families, and 91.3% did not report a history of CVD. Mean levels of Pb, Cd, and Hg were 0.51 µg/L, 1.62 µg/L, and 1.56 µg/L, respectively. Significant differences in CVD mortality were observed between the toxic metal exposure group and those without exposure. The mortality group was associated with a higher prevalence of diabetes, higher BMI, CVD history, and higher levels of Cd and Pb but lower Hg levels. Conclusions: In conclusion, our study revealed a higher prevalence of cardiovascular mortality in individuals with elevated blood Pb and Cd levels. In contrast, those with higher blood Hg levels exhibited reduced cardiovascular mortality