Association Between Serum Copper and Stroke Risk Factors in Adults: Evidence from the National Health and Nutrition Examination Survey, 2011-2016

Copper as an essential trace element is hypothesized to be involved in stroke risk. However, the evidence for associations between copper and stroke risk factors such as lipid levels has been mixed. This study aimed to examine the relationships between serum copper and lipid levels among 3425 participants aged 20 years and older from the 2011-2016 National Health and Nutrition Examination Survey (NHANES). Data on administered questionnaires, serum copper concentrations, and lipid levels (total cholesterol, HDL cholesterol, triglycerides, and LDL cholesterol) were used. Associations between serum copper and lipid levels were evaluated using both multivariable linear regression and logistic regression models. In the linear regression models, total cholesterol and LDL cholesterol levels increased with increasing copper concentrations among women. Each 1 unit (mu g/dL) increase in serum copper concentrations was associated with roughly 0.11 mg/dL higher total cholesterol (95%CI: 0.04-0.18; P < 0.05) and roughly 0.09 mg/dL higher LDL cholesterol (95%CI: 0.01-0.17; P < 0.05) among women, respectively. Serum copper was positively associated with high LDL cholesterol among women, and the multivariate-adjusted OR (95% CI) for the third quartile of serum copper concentrations was 4.25 (1.15-15.77) compared with the lowest quartile. Moreover, compared with the lowest quartile, the multivariate-adjusted OR (95% CI) for the third quartile of serum copper concentrations was 1.82 (1.16-2.85) for risk of having high total cholesterol among men. No significant association between serum copper and triglycerides levels was observed. These findings suggest that copper may impact stroke health via effects on lipid levels but need to be confirmed with prospective data.