The Association of Urinary Zinc with Metabolic Syndrome and the Mediating Role of Liver Enzymes in the Bouyei Ethnic Group in China.

Metabolic Syndrome (MetS) is a major public health problem that has imposed enormous socio-economic burdens in most countries and regions. This study aims to investigate the association of urinary Zinc (Zn) with the risk of MetS and its components among the Bouyei ethnic group, and the role of liver enzymes as mediators in this relationship. Zn concentrations in the urine of 5033 participants were measured by inductively coupled plasma mass spectrometry. An automatic biochemical analyzer was used to detect blood biochemical indexes. Binary logistic regression showed that compared with Q1, the OR (95% CI) for MetS, hyperglycemia, and elevated triglyceride in Q4 were 2.22 (1.69-2.92), 2.35 (1.73-3.18), and 1.38 (1.15-1.66), respectively. The results of the mediation analysis showed that liver enzyme may act as a partial mediator of the association between urinary Zn and MetS, with the mediating effect of gamma glutamyl transferase (GGT) accounting for 11.60% of the total effect. In conclusion, we found that urinary Zn was positively associated with MetS and its components among the Bouyei ethnic group in Guizhou Province. GGT appeared to play a partial mediating role between urinary Zn and the risk of MetS.