Association depressive symptoms with memory function and social capital before and during COVID-19 in community-dwelling older adults in rural Japan: A retrospective study with a longitudinal data

Objectives: This study aimed to investigate the impact of memory function and social capital on depressive symptoms during the COVID-19 pandemic among older adults in rural Japan.

Methods: A retrospective study with longitudinal data was conducted during COVID-19 from May 2021 to November 2021 (T2) in Kurogawa, Japan. The candidate population for this study was 145 with the following requirements: (1) older individuals aged 65 years or above who were registered in the Kurogawa study, and (2) those with previous data (from November 2016 to February 2020; T1 as pre-pandemic). Memory function was assessed using the Wechsler Memory Scale-Revised Logical Memory II delayed recall part A (LM II-DR). Depressive symptoms were assessed using the Japanese version of the 15-item Geriatric Depression Scale (GDS-15). Social capital was evaluated through civic participation, social cohesion, and reciprocity. Fear of the COVID-19 infection (FCV-19S) was evaluated.

Results: The final analysis included 96 participants (mean age = 81.0 years, SD = 4.8) Multivariate analysis for GDS-15 score by Mixed Model Repeated Measures (MMRM) revealed significant associations between LM II-DR (β = -0.13, 95% CI: -0.21-0.05, p = 0.002) and FCV-19S during COVID-19 (β = 0.08, 95% CI: 0.01-0.15, p = 0.02) with GDS-15 score. However, civic participation, social cohesion and reciprocity were not associated with GDS-15 score.

Conclusions: Among older adults in rural Japan, memory function and fear of the COVID-19 infection were significantly associated with depressive symptoms in MMRM analysis. However, social capital was not associated with depressive symptoms. This highlights the need to address memory function and fear of the COVID-19 infection in interventions for older adults during crises like the COVID-19 pandemic.