AUTHOR=Hao Lixiao , Jia Jianguo , Xing Yue , Han Ying 

TITLE=APOE ε4 Allele Distribution and Association With Scores of Subjective Cognitive Decline Questionnaire 9 in a Large Chinese Memory Clinic Cohort

JOURNAL=Frontiers in Neuroscience

VOLUME=16

YEAR=2022

URL=https://www.frontiersin.org/journals/neuroscience/articles/10.3389/fnins.2022.829031

DOI=10.3389/fnins.2022.829031

ISSN=1662-453X

ABSTRACT=<sec><title>Background</title><p>Previous reports on <italic>APOE</italic> ε4 allele distribution in different populations have been inconclusive. The Subjective Cognitive Decline-Questionnaire 9 (SCD-Q9) was developed to identify those at risk of objective cognitive impairment [OCI; including mild cognitive impairment (MCI) and dementia groups), but its association with <italic>APOE</italic> ε4 and discriminatory powers for SCD<sub><italic>with subtle cognitive decline</italic></sub> (SCDs) and OCI in memory clinics are unclear.</p></sec><sec><title>Objectives</title><p>To investigate demographic distribution of <italic>APOE</italic> ε4, its association with SCD-Q9 scores, and its ability to discriminate SCDs and OCI groups from normal control (NC).</p></sec><sec><title>Methods</title><p>A total of 632 participants were recruited (NC = 243, SCDs = 298, OCI = 91). <italic>APOE</italic> ε4 allele distribution and association with SCD-Q9 scores were calculated and the effects on cognitive impairment were analyzed. Receiver operating characteristic (ROC) analysis was applied to identify discriminatory powers for NC, SCDs, and OCI.</p></sec><sec><title>Results</title><p>Total <italic>APOE</italic> ε4 frequency was 13.1%. This did not vary by demography but was higher in patients with OCI. The SCD-Q9 scores were higher in <italic>APOE</italic> ε4 carriers than non-carriers in the OCI group. The area under the curve (AUC) for discriminating from OCI using <italic>APOE</italic> ε4 were 0.587 and 0.575, using SCD-Q9 scores were 0.738 and 0.571 for NC and SCDs groups, respectively. When we combined <italic>APOE</italic> ε4 and SCD-Q9 scores into the model, the AUC increased to 0.747 for discriminating OCI from NC. However, when OCI group was split into MCI and dementia groups, only total SCD-Q9 score was the independent affecting factor of MCI.</p></sec><sec><title>Conclusion</title><p>This study demonstrated that the distribution of <italic>APOE</italic> ε4 alleles did not vary with different demographic characteristics in a large-scale cohort from a memory clinic. <italic>APOE</italic> ε4 alleles may be associated with scores of SCD-Q9 reflecting the degree of cognitive complaints but their additional contribution to SCD-Q9 scores is marginal in discriminating between NC, SCDs, and OCI.</p></sec>