The present study demonstrated that plasma Aβ1-40, Aβ1-42, and Aβ1-42/Aβ1-40 had a decreasing trend, while plasma t-tau, NfL, and p-tau181 escalated along the different stages of cognitive impairment as the CDR score increased from 0 to 3. This evidence concerns the gene NEFL and Cognitive impairment.