We selected the most common clinical renal function tests, including creatinine-based estimated glomerular filtration rate (eGFR-cre), cystatin C-based estimated glomerular filtration rate (eGFR-cys), and UACR, as renal function indices of interest, and selected single-nucleotide polymorphisms (SNPs) associated with these indices as instrumental variables to assess whether impaired renal function causally affects the risk of dementia. Here, CST3 is linked to dementia.