Fig. 1: Enrollment and grouping of participants with major depressive disorder (MDD), subjective cognitive decline (SCD), or neither (NC).

Participants over 50 were included in the study, but only those without major organ failure (such as heart, renal, or liver failure) and unimpaired cognitive function were included. Using the Mini-International Neuropsychiatric Interview (MINI), participants with MDDs were segmented into an MDD group. Those without psychiatric disorders but with subjective cognitive problems (AD8 score ≥ 2) were segmented into an SCD group, whereas those without such problems were segmented into an NC group.