Methods: We used data from the Korea National Health and Nutrition Examination Survey (KNHANES) conducted in 2010. Serum levels of heavy metals such as mercury, cadmium, and lead were measured. Total and Df specific IgE were measured, and urinary cotinine level was investigated. Information about participant sex, age, body mass index (BMI), and household income were also obtained. Data from 2184 participants were analyzed. Multivariate linear regression analyses were used to determine the independent effects of these variables.
Results: We found that serum lead concentration was positively correlated with total IgE using Spearman’s correlation test (Spearman’s rho = 0.150, p < 0.001). BMI, serum mercury level, and urine cotinine level was also positively correlated with total IgE. In an adjusted linear regression analysis, only serum concentration of lead among the three heavy metals was positively associated with logarithmic transformed total IgE [LogTIgE; coefficient (B) = 0.026, 95% confidence interval (CI) = 0.008-0.044]. When we performed the same analysis on groups divided by allergic Df sensitization status, we found a significant positive association between serum lead and LogTIgE in subjects with Df sensitization (B = 0.076, 95% CI = 0.003-0.150) but not in subjects without Df sensitization (B = 0.015, 95% CI = -0.008-0.039).
Conclusions: Serum lead level was positively associated with total IgE level. However, this correlation was statistically significant in subjects with Df sensitization. This result suggests that the immunologic effects of lead exposure may be greater in people with allergic sensitization.