Positive Association between Urinary Concentration of Lead, Cadmium and Subclinical Atherosclerosis in Adolescents and Young Adults

Abstract

Backgrounds: Urinary cadmium and lead have been associated with hypertension and cardiovascular diseases (CVD) in large population studies. However, there are still limited information linking exposure to heavy metal with subclinical atherosclerosis, particularly in young population.Methods: From a nationwide mass urine screening for renal health, conducted in 1992-2000 among school children 6 to 18 years of age in Taiwan, we recruited 789 subjects to participate in the cardiovascular health examination in 2006-2008. In the present study we evaluated the association between urinary levels of cadmium, lead, chromium, manganese, iron, nickel, copper, and zinc with carotid intima-media thickness (CIMT) in a cross-sectional analysis of 739 adolescents and young adults.Results: CIMT at all segments of carotid arteries significantly increased with the urinary lead and cadmium in a dose-response relationship after adjustment for major CVD risk factors. Multivariate logistic regression analysis showed that higher quartiles of urinary concentrations of lead and cadmium were associated with a higher risk of thicker CIMT (greater than 75th percentile). Compared to subjects with the lowest quartile (Q1) of urinary lead, the adjusted odds ratios (aORs) (95% confidence interval (CI)) for thicker CIMT among subjects with higher urinary lead were 2.56(1.35-4.85) for Q2, 3.76(2.00-7.08) for Q3, and 17.64(9.32-33.39) for subjects at Q4. Comparing those with lowest urinary cadmium, the corresponding aORs (95% CI) were 1.48(0.77-2.85) for Q2, 4.68(2.57-8.52) for Q3, and 13.58(7.34-25.13) for subjects at Q4.Conclusion: Higher urinary concentration of lead and cadmium was strongly associated with subclinical atherosclerosis in adolescents and young adults.