Within the implicated loci on chromosome 19, we identified several pleiotropic genes, including BCAM, TOMM40, NECTIN2, APOE, APOC1, CBLC, APOC4, APOC2, APOC4-APOC2, EXOC3L2, and CLPTM1. These genes exhibited significant associations with both CAC or AAC and AD or cognitive traits, indicating their role in the genetic architecture of these conditions and the potential co-occurrence of CAC/AAC with AD and cognitive decline. This evidence concerns the gene APOC1 and Alzheimer disease.