Background: The long-term associationsbetween serum cobalt (Co), copper (Cu) and selenium (Se) intake and the risk of type 2 diabetes mellitus (T2DM) are unclear. This study aimed to explore the relationship between serum Co, Cu, and Se intake and the risk of T2DM in rural areas of central China.
Methods: We used the method developed by our group for the simple, rapid and accurate detection of elements in serum by ICP-MS. Determine T2DM through valid questionnaires and laboratory tests. The Poisson regression model based on robustness under generalized linear regression was used to analyze metals, and the BKMR model was used to analyze the interaction of three mixed metals.
Results: A total of 3817 adults were included in the rural cohort study in Henan, and a total of 177 patients with T2DM were diagnosed. In the polymetallic model, stratified analyses revealed an overall negative correlation between serum Co, with intermediate concentrations associated with a non-significant risk of T2DM and high concentrations associated with a 34% (95% CI: 0.44, 1.00) reduction in the risk of T2DM relative to low concentrations. Serum Se was negatively correlated overall, with intermediate concentrations associated with a 41% (95% CI: 0.40, 0.85) lower risk of developing T2DM and high concentrations associated with a non-significant risk of developing T2DM, relative to low concentrations; A significant interaction between serum Se and age (P < 0.049) was found within each stratum, with significant interactions between age and T2DM, and a significant interaction between age and T2DM within each stratum. A significant interaction was found between serum Se and age (P < 0.049), with the negative association of serum Se with T2DM being enhanced in the younger (< 60 years) study population, and a significant interaction was found between serum Co levels and gender (P < 0.012), with the negative association of serum Co with T2DM also being enhanced in the female study population.
Conclusion: Cobalt metal exposure was protective in the development of diabetes and was stronger in the female population; selenium metal exposure was protective in the development of diabetes and was stronger in people younger than 60 years.