Shorter Telomere Length in Individuals with Neurocognitive Disorder and APOE-ε4 Genotype

Neurocognitive disorders (NCD) are neurodegenerative diseases characterized by decline or loss of cognitive function. Two main risk factors for this condition have been identified: age and the APOE genotype. One of the proposed mechanisms of aging is telomere length (TL), as an association between shorter TL and NCD has been suggested. This study investigated the relationship between TL and the APOE genotype in individuals with neurocognitive impairment (CI). 170 participants aged > 60 years were included. Cognitive function was assessed using MMSE and MoCA tests. Relative telomere quantification and APOE genotyping were performed using RT-PCR. A shorter TL was significantly associated with an increased risk of CI (p < 0.001). The APOE ε4 genotype showed a less significant association, with individuals not carrying the ε4 allele displaying a higher risk of CI (p < 0.05). However, a trend toward shorter TL were observed in individuals carrying the ε4 allele with CI compared to those Non-Cognitive Impairment with subjective memory Complaint. Additionally, the number of years of education was negatively correlated with CI (p < 0.0001). Individuals with shorter TL and fewer years of education demonstrated a higher risk of CI. APOE genotype would be a risk factor for shorter telomeres.