Objective: The current study was conducted to analyze the association between the serum concentrations of heavy metals (lead, mercury, and cadmium) with the metabolic syndrome (MS) prevalence and its individual components according to the gender in Korean population.

Methods: We separately evaluated a sample size of 1822 patients (896 males, 926 females) with age of 20 or older who were registered for the Korea National Health and Nutrition Examination Survey (KNHANES) VI, 2013. We expected that as heavy metal concentrations increase, the prevalence of MS may vary according to the gender. Furthermore, we also presumed that the association between the heavy metal concentration and MS prevalence along with its components may show different result across the genders after adjusting certain variables (age, status of smoking, alcohol consumption, and exercise).

Results: The concentrations of the heavy metal levels were significantly higher in MS group of both genders. Pearson’s chi-square test revealed that as concentrations of heavy metals increase above cut-off value, the prevalence of MS also significantly increase in both genders; however, linear-by-linear association analysis demonstrated the significant linear increase of MS prevalence according to the elevation of heavy metal concentrations in female group while the male group showed non-significant association. Furthermore, no significant association between heavy metal concentrations and MS prevalence was maintained in male population after adjustment of certain variables, which were either well known risk factors or demonstrated as independent factors of MS after univariate analysis. Contrary to the male group, higher serum lead concentration (Odd ratio [OR]: 1.277, 95% confidence interval [CI]: 1.017-1.602, p=0.035), diastolic blood pressure (OR: 1.469, 95% CI: 1.148-1.880, p=0.002), and high triglyceride level (OR: 1.247, 95% CI: 1.015-1.532, p=0.036) were related to higher prevalence of MS in female group. Moreover, the serum mercury level showed a close relationship with fasting blood sugar (OR: 1.074, 95% CI: 1.004-1.148, p=0.039), triglyceride (OR: 1.029, 95% CI: 0.961-1.102, p=0.029), and the prevalence of MS (OR: 1.082, 95% CI: 1.007-1.163, p=0.032) in females.

Conclusions: The intimate association existed between the concentrations of heavy metals and MS prevalence in female group rather than male.