Causal Effect of Genetically Determined Blood Copper Concentrations on Multiple Diseases: A Mendelian Randomization and Phenome-Wide Association Study

Exposures to copper have become a health concern.We aim to explore the broad clinical effects of blood copper concentrations.A total of 376,346 Caucasian subjects were enrolled.We performed a Mendelian randomization and phenome-wide association study(MR-PheWAS)to evaluate the causal association between copper and a wide range of outcomes in UK Biobank,and we constructed a protein-protein interaction network.We found association between blood copper concentrations and five diseases in the overall population and nine diseases in male.MR analysis implicated a causal role of blood copper in five diseases(overall population),including prostate cancer(OR=0.87,95%CI 0.77-0.98),malignant and unknown neoplasms of the brain and nervous system(OR=0.58,95%CI 0.38-0.89),and hypertension(OR=0.94,95%CI 0.90-0.98),essential hypertension(OR=0.94,95%CI 0.90-0.98)and cancer of brain and nervous system(OR=0.63,95%CI 0.41-0.98).For male,except for dysphagia being newly associated with blood copper(OR=1.39,95%CI 1.18-1.63),other MR results were consistent with the overall population.In addition,the PPI network showed possible relationship between blood copper and four outcomes,namely brain cancer,prostate cancer,hypertension,and dysphagia.Blood copper may have causal association with prostate cancer,malignant and unknown neoplasms of the brain and nervous system,hypertension,and dysphagia.Considering that copper is modifiable,exploring whether regulation of copper levels can be used to optimize health outcomes might have public health importance.