Higher Serum Heavy Metal May Be Related with Higher Serum gamma-Glutamyltransferase Concentration in Koreans: Analysis of the Fifth Korea National Health and Nutrition Examination Survey (KNHANES V-1, 2, 2010, 2011) / 가정의학회지

ABSTRACT

BACKGROUND: Abnormal serum gamma-glutamyltransferase (gamma-GT) may be an early and sensitive marker for oxidative stress. This study was performed to evaluate the association between serum heavy metals and gamma-GT concentration. METHODS: This study is a cross-sectional analysis based on data from Korean National Health and Nutrition Examination Survey (V-1, 2, 2010, 2011) regarding serum heavy metal concentrations (lead, mercury, and cadmium) as well as serum gamma-GT. Serum heavy metals were categorized into tertiles, and serum gamma-GT concentration was compared using an analysis of covariance test after relevant variable adjustments. In addition, we evaluated the odds ratio (OR) of having the highest tertile of serum gamma-GT in each heavy metal tertile using logistic regression. RESULTS: The mean serum lead, mercury, and cadmium concentrations were 2.67, 5.08, and 1.02 microg/dL in men and 1.95, 3.60, and 1.21 microg/dL in women, respectively. Partial correlation showed a significant positive relation between each heavy metal and serum gamma-GT concentration. Comparing serum gamma-GT concentration by the tertile of each heavy metal, serum gamma-GT concentration showed a significant increase as the tertiles of serum mercury and cadmium in men and that of serum mercury in women increased, but not with lead. The OR of having the highest tertile of serum gamma-GT was significant for cadmium in men (OR, 4.02; 95% confidence interval [CI], 2.54 to 6.35) and mercury in women (OR, 2.00; 95% CI, 1.29 to 3.10) in the top tertile of each heavy metal. CONCLUSION: Higher serum heavy metal concentration may be related with higher serum gamma-GT concentration. In particular, serum cadmium in men and mercury in women showed significant correlation with serum gamma-GT concentration.