Increased erythrocyte lead levels correlate with decreased hemoglobin levels in the Korean general population: analysis of 2008–2010 Korean National Health and Nutrition Examination Survey data
Introduction We present data from the Korean National Health and Nutrition Examination Survey 2008–2010 on the association between blood lead and hemoglobin levels in a representative sample of the adult South Korean population.
Methods The analysis was restricted to participants ≥20 years of age who completed the health examination survey, including blood lead measurements (n = 5,951). Multivariate linear regression analyses were performed to estimate adjusted mean differences in hemoglobin level associated with doubling of whole blood and erythrocyte lead or quartiles of the metal after covariate adjustment. Odds ratios (ORs) for having borderline anemia or clinical anemia were calculated for log-transformed whole blood and erythrocyte lead or quartiles of the metal after covariate adjustment.
Results A twofold increase in whole blood lead or erythrocyte lead was associated with a 0.285 g/dL increase or 0.088 g/dL decrease in hemoglobin level, respectively. There was a 0.416 g/dL increase or 0.143 g/dL decrease in hemoglobin, respectively, in the highest, compared with the lowest tertile of whole blood lead and erythrocyte lead, respectively. Based on ORs, doubling of whole blood lead or erythrocyte lead resulted in a 36.3 % decrease or 36.2 % increase, respectively, in the risk of borderline anemia.
Conclusion The association of whole blood lead versus erythrocyte lead with hemoglobin level was opposite. In the case of anemia, which is frequently caused by iron deficiency, the effect on the whole blood lead concentration may be very significant, leading to a considerable underestimation of the person’s lead status. Therefore, hematocrit-adjusted blood lead level (i.e., erythrocyte lead) should be applied to the general population. To our knowledge, this is the first study to show that erythrocyte lead levels showed a significant inverse relationship with hemoglobin level at lead levels <10 μg/dL in the general Korean population. In conclusion, increased erythrocyte lead levels may be associated with mildly decreased hemoglobin levels, after adjusting for covariates, in a representative sample of the adult Korean population.