The association between six heavy metal levels and the risk of liver fibrosis in women without gestational diabetes mellitus

BACKGROUND: To investigate the association between exposure to six heavy metals (Pb, Cd, Mn, Se, total Hg, and MeHg) in the blood and the risk of liver fibrosis in populations with and without a history of GDM. METHODS: Data were retrospectively gathered from the 2011-2018 NHANES database. Interaction tests (metal × GDM) were performed in multivariable logistic regression to formally assess effect modification by GDM. Logistic regression was utilized to confirm the association between heavy metals and liver fibrosis risk. The WQS and BKMR models were applied to evaluate the combined effect of heavy metal mixtures on liver fibrosis risk. RESULTS: Interaction tests showed significant GDM interactions for log Pb (P for interaction=0.039), log total Hg (P for interaction =0.033), and log MeHg (P for interaction =0.037) in liver fibrosis. After FDR correction, fully adjusted logistic regression results showed that log Pb (OR=5.685, 95%CI: 4.230-7.665, q < 0.001), log Cd (OR=3.076, 95%CI: 2.291-4.141, q < 0.001), and log Se (OR=0.147, 95%CI: 0.039-0.548, q = 0.009) were related to liver fibrosis risk in the group without a history of GDM. WQS and BKMR results indicated that the overall impact of co-exposure to six heavy metals on liver fibrosis risk was positively correlated, with log Pb, log Cd, and log Se playing a dominant role in the mixed effects on the risk of liver fibrosis. CONCLUSIONS: log Pb, log Cd, and log Se were significantly associated with the risk of liver fibrosis in women without a history of GDM.