Association of Blood Cadmium Level with Cardiometabolic Risk Factors and Liver Enzymes in a Nationally Representative Sample of Adolescents: The CASPIAN-III Study

Introduction. This study aimed to determine the association of blood cadmium level with cardiometabolic risk factors and liver enzymes in adolescents. Methods. This case control study comprised 320 Iranian adolescents, 160 with metabolic syndrome and an equal number of controls. They were selected from participants of a nationwide survey entitled the CASPIAN-III study. Cadmium was measured by atomic absorption method. Results. The mean age of the case and control groups was not significantly different ( versus years, resp., ). The mean cadmium level was near double-fold higher than the standards of the World Health Organization, without significant difference between the MetS and control groups ( , ？μg/L, resp., ). Cadmium level had positive but nonsignificant correlations with diastolic blood pressure, serum triglycerides, fasting blood glucose, LDL-C, and liver enzymes. Conclusion. Cadmium level had positive but nonsignificant association with some cardiometabolic risk factors and liver enzymes. The associations did not reach statistical significant level, and this may be because of the high levels of cadmium in both groups studied or because of the young age group of participants. Controlling environmental pollutants shall be a priority for the prevention of chronic diseases. 1. Introduction Metabolic syndrome (MetS) is an emerging health problem at global level and increases the risk of most chronic diseases. It origins from early life and consists of various components including obesity, elevated blood pressure, elevated serum glucose, and dyslipidemia in terms of increased triglycerides and reduced high-density lipoprotein cholesterol (HDL cholesterol) levels [1]. It is no more limited to the western countries and adult populations [2, 3]. Asians have an ethnic predisposition to MetS, and it is one of health concerns in Iran [4, 5]. MetS is a multifactorial condition, and in addition to genetic and lifestyle factors, environment influences the development of this disorder [6]. Heavy metals are one of the environmental factors that may have a role in this regard. Heavy metals or toxic metals such as mercury, lead, and cadmium have no biological function in human system and are potentially toxic even at trace concentrations. Cadmium can enter into blood stream by eating and drinking cadmium-contaminated food or water and/or by breathing cadmium-contaminated air [7–9]. Lee and Kim reported for the first time that blood cadmium level is a risk factor for MetS [9]. Various studies showed that urinary cadmium levels are significantly and dose